Evidence for a Cognitive Control Network for Goal-Directed Attention in Simple Sustained Attention
ERIC Educational Resources Information Center
Hilti, Caroline C.; Jann, Kay; Heinemann, Doerthe; Federspiel, Andrea; Dierks, Thomas; Seifritz, Erich; Cattapan-Ludewig, Katja
2013-01-01
The deterioration of performance over time is characteristic for sustained attention tasks. This so-called "performance decrement" is measured by the increase of reaction time (RT) over time. Some behavioural and neurobiological mechanisms of this phenomenon are not yet fully understood. Behaviourally, we examined the increase of RT over time and…
ERIC Educational Resources Information Center
Kolbe, Tammy; O'Reilly, Fran
2017-01-01
A growing number of public schools have adopted reforms that increase the amount of time students spend in school. However, the potential costs of such reforms are not well understood. In this article, we report findings from a resource-cost study conducted in four schools that participated in the Massachusetts Expanded Learning Time Initiative.…
What makes Great Basin sagebrush ecosystems invasible by Bromus tectorum?
Jeanne C. Chambers; Bruce A. Roundy; Robert R. Blank; Susan E. Meyer; A. Whittaker
2007-01-01
Ecosystem susceptibility to invasion by nonnative species is poorly understood, but evidence is increasing that spatial and temporal variability in resources has large-scale effects. We conducted a study in Artemisia tridentata ecosystems at two Great Basin locations examining differences in resource availability and invasibility of Bromus...
ERIC Educational Resources Information Center
Lind, Catherine; Mirchandani, Gita G.; Castrucci, Brian C.; Chavez, Noel; Handler, Arden; Hoelscher, Deanna M.
2012-01-01
Background: Childhood obesity is a national epidemic that disproportionately affects Hispanic children. Evidence suggests that increased acculturation among this population adversely affects diet and other healthy lifestyle characteristics, leading to higher rates of overweight and obesity. Healthy lifestyle characteristics must be understood in…
Evidence of current impact of climate change on life: a walk from genes to the biosphere.
Peñuelas, Josep; Sardans, Jordi; Estiarte, Marc; Ogaya, Romà; Carnicer, Jofre; Coll, Marta; Barbeta, Adria; Rivas-Ubach, Albert; Llusià, Joan; Garbulsky, Martin; Filella, Iolanda; Jump, Alistair S
2013-08-01
We review the evidence of how organisms and populations are currently responding to climate change through phenotypic plasticity, genotypic evolution, changes in distribution and, in some cases, local extinction. Organisms alter their gene expression and metabolism to increase the concentrations of several antistress compounds and to change their physiology, phenology, growth and reproduction in response to climate change. Rapid adaptation and microevolution occur at the population level. Together with these phenotypic and genotypic adaptations, the movement of organisms and the turnover of populations can lead to migration toward habitats with better conditions unless hindered by barriers. Both migration and local extinction of populations have occurred. However, many unknowns for all these processes remain. The roles of phenotypic plasticity and genotypic evolution and their possible trade-offs and links with population structure warrant further research. The application of omic techniques to ecological studies will greatly favor this research. It remains poorly understood how climate change will result in asymmetrical responses of species and how it will interact with other increasing global impacts, such as N eutrophication, changes in environmental N : P ratios and species invasion, among many others. The biogeochemical and biophysical feedbacks on climate of all these changes in vegetation are also poorly understood. We here review the evidence of responses to climate change and discuss the perspectives for increasing our knowledge of the interactions between climate change and life. © 2013 John Wiley & Sons Ltd.
Drug effects on responses to emotional facial expressions: recent findings.
Miller, Melissa A; Bershad, Anya K; de Wit, Harriet
2015-09-01
Many psychoactive drugs increase social behavior and enhance social interactions, which may, in turn, increase their attractiveness to users. Although the psychological mechanisms by which drugs affect social behavior are not fully understood, there is some evidence that drugs alter the perception of emotions in others. Drugs can affect the ability to detect, attend to, and respond to emotional facial expressions, which in turn may influence their use in social settings. Either increased reactivity to positive expressions or decreased response to negative expressions may facilitate social interaction. This article reviews evidence that psychoactive drugs alter the processing of emotional facial expressions using subjective, behavioral, and physiological measures. The findings lay the groundwork for better understanding how drugs alter social processing and social behavior more generally.
ERIC Educational Resources Information Center
Symons, Frank J.; Harper, Vicki N.; McGrath, Patrick J.; Breau, Lynn M.; Bodfish, James W.
2009-01-01
The role of pain in relation to self-injurious behavior (SIB) among individuals with intellectual disabilities is not well understood. Some models of SIB are based on altered endogenous opioid system activity which could result in elevated pain thresholds. In this study, non-verbal behavioral signs indicative of pain as measured by the…
Drug effects on responses to emotional facial expressions: recent findings
Miller, Melissa A.; Bershad, Anya K.; de Wit, Harriet
2016-01-01
Many psychoactive drugs increase social behavior and enhance social interactions, which may, in turn, increase their attractiveness to users. Although the psychological mechanisms by which drugs affect social behavior are not fully understood, there is some evidence that drugs alter the perception of emotions in others. Drugs can affect the ability to detect, attend to, and respond to emotional facial expressions, which in turn may influence their use in social settings. Either increased reactivity to positive expressions or decreased response to negative expressions may facilitate social interaction. This article reviews evidence that psychoactive drugs alter the processing of emotional facial expressions using subjective, behavioral, and physiological measures. The findings lay the groundwork for better understanding how drugs alter social processing and social behavior more generally. PMID:26226144
ERIC Educational Resources Information Center
Gomes da Silva, Sérgio; de Almeida, Alexandre Aparecido; Fernandes, Jansen; Lopim, Glauber Menezes; Cabral, Francisco Romero; Scerni, Débora Amado; de Oliveira-Pinto, Ana Virgínia; Lent, Roberto; Arida, Ricardo Mario
2016-01-01
Clinical evidence has shown that physical exercise during pregnancy may alter brain development and improve cognitive function of offspring. However, the mechanisms through which maternal exercise might promote such effects are not well understood. The present study examined levels of brain-derived neurotrophic factor (BDNF) and absolute cell…
Alternative, Complementary, and Forgotten Remedies for Atopic Dermatitis
Goddard, Allison L.; Lio, Peter A.
2015-01-01
Atopic dermatitis, perhaps more than other dermatologic diseases, has garnered much attention in the realm of alternative medicine. This may be because its etiopathogenesis is incompletely understood, it is increasingly common, and it waxes and wanes often without clear precipitants, opening up many opportunities for misinterpretation. Herein we explore the evidence for a number of different alternative and complementary therapies, from textiles to vitamin supplements. By definition, none have enough data to be deemed “effective” in a conventional sense, but it is hopeful that some show promising evidence that may one day lead to mainstream acceptance with further research. PMID:26257817
2012-01-01
Although the neurobiological mechanisms underlying panic disorder (PD) are not yet clearly understood, increasing amount of evidence from animal and human studies suggests that the amygdala, which plays a pivotal role in neural network of fear and anxiety, has an important role in the pathogenesis of PD. This article aims to (1) review the findings of structural, chemical, and functional neuroimaging studies on PD, (2) relate the amygdala to panic attacks and PD development, (3) discuss the possible causes of amygdalar abnormalities in PD, (4) and suggest directions for future research. PMID:23168129
Impact of Diabetic Complications on Balance and Falls: Contribution of the Vestibular System
Lin, James; Staecker, Hinrich; Whitney, Susan L.; Kluding, Patricia M.
2016-01-01
Diabetes causes many complications, including retinopathy and peripheral neuropathy, which are well understood as contributing to gait instability and falls. A less understood complication of diabetes is the effect on the vestibular system. The vestibular system contributes significantly to balance in static and dynamic conditions by providing spatially orienting information. It is noteworthy that diabetes has been reported to affect vestibular function in both animal and clinical studies. Pathophysiological changes in peripheral and central vestibular structures due to diabetes have been noted. Vestibular dysfunction is associated with impaired balance and a higher risk of falls. As the prevalence of diabetes increases, so does the potential for falls due to diabetic complications. The purpose of this perspective article is to present evidence on the pathophysiology of diabetes-related complications and their influence on balance and falls, with specific attention to emerging evidence of vestibular dysfunction due to diabetes. Understanding this relationship may be useful for screening (by physical therapists) for possible vestibular dysfunction in people with diabetes and for further developing and testing the efficacy of interventions to reduce falls in this population. PMID:26251477
Dynamic Neuroplasticity after Human Prefrontal Cortex Damage
Voytek, Bradley; Davis, Matar; Yago, Elena; Barceló, Francisco; Vogel, Edward K.; Knight, Robert T.
2010-01-01
Summary Memory and attention deficits are common after prefrontal cortex (PFC) damage, yet people generally recover some function over time. Recovery is thought to be dependent upon undamaged brain regions but the temporal dynamics underlying cognitive recovery are poorly understood. Here we provide evidence that the intact PFC compensates for damage in the lesioned PFC on a trial-by-trial basis dependent on cognitive load. The extent of this rapid functional compensation is indexed by transient increases in electrophysiological measures of attention and memory in the intact PFC, detectable within a second after stimulus presentation and only when the lesioned hemisphere is challenged. These observations provide evidence supporting a dynamic and flexible model of compensatory neural plasticity. PMID:21040843
Effective management of low back pain: it’s time to accept the evidence
Manga, Pran; Angus, Douglas E; Swan, William R
1993-01-01
Low back pain is a ubiquitous and economically costly problem. Unfortunately, the clinical management of low back pain is not yet well understood. Chiropractic management of back pain, long the black sheep of back care, has undergone a transition and is now a more respected and understood alternative to conservative medical care, itself under increased scrutiny due to unsatisfactory outcomes and unacceptable iatrogenic side effects. The substantial amount of clinical and related research on the effectiveness of manipulation for low back pain is summarized here from a larger study, divided into randomized control trials, case-control trials, meta-analyses and descriptive studies. The chiropractic management of low back pain is found to be a more effective way of dealing with this medical, social and economic problem. It is suggested that greater utilization of chiropractors be encouraged such that the “right people are doing the right things at the right time”.
Multi-symptom illnesses, unexplained illness and Gulf War Syndrome
Ismail, Khalida; Lewis, Glyn
2006-01-01
Explanatory models for the increased prevalence of ill health in Gulf veterans compared to those not deployed to the Gulf War 1990–1991 remain elusive. This article addresses whether multi-symptom reporting in Gulf veterans are types of medically unexplained symptoms and whether the alleged Gulf War Syndrome is best understood as a medically unexplained syndrome. A review of the epidemiological studies, overwhelmingly cross-sectional, describing ill health was conducted including those that used factor analysis to search for underlying or latent clinical constructs. The overwhelming evidence was that symptoms in Gulf veterans were either in keeping with currently defined psychiatric disorders such as depression and anxiety or were medically unexplained. The application of factor analysis methods had varied widely with a risk of over interpretation in some studies and limiting the validity of their findings. We concluded that ill health in Gulf veterans and the alleged Gulf War Syndrome is best understood within the medically unexplained symptoms and syndromes constructs. The cause of increased reporting in Gulf veterans are still not clear and requires further inquiry into the interaction between sociological factors and symptomatic distress. PMID:16687260
An imaging genetics approach to understanding social influence
Falk, Emily B.; Way, Baldwin M.; Jasinska, Agnes J.
2012-01-01
Normative social influences shape nearly every aspect of our lives, yet the biological processes mediating the impact of these social influences on behavior remain incompletely understood. In this Hypothesis, we outline a theoretical framework and an integrative research approach to the study of social influences on the brain and genetic moderators of such effects. First, we review neuroimaging evidence linking social influence and conformity to the brain's reward system. We next review neuroimaging evidence linking social punishment (exclusion) to brain systems involved in the experience of pain, as well as evidence linking exclusion to conformity. We suggest that genetic variants that increase sensitivity to social cues may predispose individuals to be more sensitive to either social rewards or punishments (or potentially both), which in turn increases conformity and susceptibility to normative social influences more broadly. To this end, we review evidence for genetic moderators of neurochemical responses in the brain, and suggest ways in which genes and pharmacology may modulate sensitivity to social influences. We conclude by proposing an integrative imaging genetics approach to the study of brain mediators and genetic modulators of a variety of social influences on human attitudes, beliefs, and actions. PMID:22701416
The oxygen paradox of neurovascular coupling
Leithner, Christoph; Royl, Georg
2014-01-01
The coupling of cerebral blood flow (CBF) to neuronal activity is well preserved during evolution. Upon changes in the neuronal activity, an incompletely understood coupling mechanism regulates diameter changes of supplying blood vessels, which adjust CBF within seconds. The physiologic brain tissue oxygen content would sustain unimpeded brain function for only 1 second if continuous oxygen supply would suddenly stop. This suggests that the CBF response has evolved to balance oxygen supply and demand. Surprisingly, CBF increases surpass the accompanying increases of cerebral metabolic rate of oxygen (CMRO2). However, a disproportionate CBF increase may be required to increase the concentration gradient from capillary to tissue that drives oxygen delivery. However, the brain tissue oxygen content is not zero, and tissue pO2 decreases could serve to increase oxygen delivery without a CBF increase. Experimental evidence suggests that CMRO2 can increase with constant CBF within limits and decreases of baseline CBF were observed with constant CMRO2. This conflicting evidence may be viewed as an oxygen paradox of neurovascular coupling. As a possible solution for this paradox, we hypothesize that the CBF response has evolved to safeguard brain function in situations of moderate pathophysiological interference with oxygen supply. PMID:24149931
NASA Astrophysics Data System (ADS)
Gase, Andrew C.; Brand, Brittany D.; Bradford, John H.
2017-03-01
The causes and effects of erosion are among the least understood aspects of pyroclastic density current (PDC) dynamics. Evidence is especially limited for erosional self-channelization, a process whereby PDCs erode a channel that confines the body of the eroding flow or subsequent flows. We use ground-penetrating radar imaging to trace a large PDC scour and fill from outcrop to its point of inception and discover a second, larger PDC scour and fill. The scours are among the largest PDC erosional features on record, at >200 m wide and at least 500 m long; estimated eroded volumes are on the order of 106 m3. The scours are morphologically similar to incipient channels carved by turbidity currents. Erosion may be promoted by a moderate slope (5-15°), substrate pore pressure retention, and pulses of increased flow energy. These findings are the first direct evidence of erosional self-channelization by PDCs, a phenomenon that may increase flow velocity and runout distance through confinement and substrate erosion.
Blackie, Caroline A; Carlson, Alan N; Korb, Donald R
2015-07-01
Meibomian gland dysfunction (MGD) is understood to be a highly prevalent, chronic progressive disease and the leading cause of dry eye. All available published peer-reviewed results of the novel vectored thermal pulsation therapy for patients with MGD are investigated. The PubMed and meeting abstract search revealed a total of 31 peer-reviewed reports on vectored thermal pulsation therapy at the time of the search (eight manuscripts and 23 meeting abstracts). All manuscripts evidence a significant increase in meibomian gland function (∼3×) and symptom improvement post a single 12-min treatment. Additional reported objective measures such as osmolarity, tear break-up time, or lipid layer thickness also increased as a result of the therapy; however, not all findings were statistically significant. The randomized controlled studies evidence sustained gland function and symptom relief lasting out to 12 months. The uncontrolled case series evidence significantly longer duration of effect. A single 12 minute vectored thermal pulsation treatment allows for reducing dry eye symptoms, improving meibomian gland function and other correlates of the ocular surface health.
An Overview of Evidence-Based Program Registers (EBPRs) for Behavioral Health
Burkhardt, Jason T.; Schröter, Daniela C.; Magura, Stephen; Means, Stephanie N.; Coryn, Chris L.S.
2015-01-01
Evaluations of behavioral health interventions have identified many that are potentially effective. However, clinicians and other decision makers typically lack the time and ability to effectively search and synthesize the relevant research literature. In response to this opportunity, and to increasing policy and funding pressures for the use of evidence-based practices, a number of “what works” websites have emerged to assist decision makers in selecting interventions with the highest probability of benefit. However, these registers as a whole are not well understood. This article, which represents phase one of a concurrent mixed methods study, presents a review of the scopes, structures, dissemination strategies, uses, and challenges faced by evidence-based registers in the behavioral health disciplines. The major findings of this study show that in general, registers of evidence-based practices are able, to a degree, to identify the most effective practices and meet the needs of decision makers. However, much needs to be done to improve the ability of the registers to fully realize their purpose. PMID:25450777
Trugilho, Monique Ramos de Oliveira; Hottz, Eugenio Damaceno; Brunoro, Giselle Villa Flor; Teixeira-Ferreira, André; Carvalho, Paulo Costa; Salazar, Gustavo Adolfo; Zimmerman, Guy A; Bozza, Fernando A; Bozza, Patrícia T; Perales, Jonas
2017-05-01
Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV) infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P) translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet proteome in dengue, and sheds light on new mechanisms of platelet activation and platelet-mediated immune and inflammatory responses.
Teixeira-Ferreira, André; Carvalho, Paulo Costa; Salazar, Gustavo Adolfo; Zimmerman, Guy A.; Perales, Jonas
2017-01-01
Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV) infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P) translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet proteome in dengue, and sheds light on new mechanisms of platelet activation and platelet-mediated immune and inflammatory responses. PMID:28542641
Lee, Mi-Jeong; Pramyothin, Pornpoj; Karastergiou, Kalypso; Fried, Susan K
2014-03-01
Central obesity is associated with insulin resistance and dyslipidemia. Thus, the mechanisms that control fat distribution and its impact on systemic metabolism have importance for understanding the risk for diabetes and cardiovascular disease. Hypercortisolemia at the systemic (Cushing's syndrome) or local levels (due to adipose-specific overproduction via 11β-hydroxysteroid dehydrogenase 1) results in the preferential expansion of central, especially visceral fat depots. At the same time, peripheral subcutaneous depots can become depleted. The biochemical and molecular mechanisms underlying the depot-specific actions of glucocorticoids (GCs) on adipose tissue function remain poorly understood. GCs exert pleiotropic effects on adipocyte metabolic, endocrine and immune functions, and dampen adipose tissue inflammation. GCs also regulate multiple steps in the process of adipogenesis. Acting synergistically with insulin, GCs increase the expression of numerous genes involved in fat deposition. Variable effects of GC on lipolysis are reported, and GC can improve or impair insulin action depending on the experimental conditions. Thus, the net effect of GC on fat storage appears to depend on the physiologic context. The preferential effects of GC on visceral adipose tissue have been linked to higher cortisol production and glucocorticoid receptor expression, but the molecular details of the depot-dependent actions of GCs are only beginning to be understood. In addition, increasing evidence underlines the importance of circadian variations in GCs in relationship to the timing of meals for determining their anabolic actions on the adipocyte. In summary, although the molecular mechanisms remain to be fully elucidated, there is increasing evidence that GCs have multiple, depot-dependent effects on adipocyte gene expression and metabolism that promote central fat deposition. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease. Copyright © 2013 Elsevier B.V. All rights reserved.
Aixalà, Marc; Dos Santos, Rafael G; Hallak, Jaime E C; Bouso, José Carlos
2018-06-04
In the past decade, an increasing number of clinical trials are reporting evidence that psychedelics or serotonergic hallucinogens (such as lysergic acid diethylamide, psilocybin, and ayahuasca/dimethyltryptamine) could be effective in the treatment of mood, anxiety, and substance use disorders. The mechanisms responsible for these effects are not fully understood but seem to involve changes in bran dynamics in areas rich in serotonergic 5-HT 2A receptors and in personality. In the present text, we present a brief and critical overview of the current research in this field, pointing out both promises and limitations of these studies.
The Science of Reading Research
ERIC Educational Resources Information Center
Lyon, G. Reid; Chhabra, Vinita
2004-01-01
Educators must understand and act on scientific evidence so that the reader learns to access print accurately and fluently. The process of conducting scientific research is presented so that scientific evidence can be clearly understood by the educators to select the most effective and instructional approaches.
Targeting obesity-related adipose tissue dysfunction to prevent cancer development and progression
Gucalp, Ayca; Iyengar, Neil M.; Hudis, Clifford A.; Dannenberg, Andrew J.
2016-01-01
The incidence of obesity, a leading modifiable risk factor for common solid tumors, is increasing. Effective interventions are needed to minimize the public health implications of obesity. Although the mechanisms linking increased adiposity to malignancy are incompletely understood, growing evidence points to complex interactions among multiple systemic and tissue-specific pathways including inflamed white adipose tissue. The metabolic and inflammatory consequences of white adipose tissue dysfunction collectively provide a plausible explanation for the link between overweight/obesity and carcinogenesis. Gaining a better understanding of these underlying molecular pathways and developing risk assessment tools that identify at-risk populations will be critical in implementing effective and novel cancer prevention and management strategies. PMID:26970134
Marvar, Paul J.; Hendy, Emma B.; Cruise, Thomas D.; Walas, Dawid; DeCicco, Danielle; Vadigepalli, Rajanikanth; Schwaber, James S.; Waki, Hidefumi; Murphy, David
2016-01-01
Key points Evidence indicates an association between hypertension and chronic systemic inflammation in both human hypertension and experimental animal models.Previous studies in the spontaneously hypertensive rat (SHR) support a role for leukotriene B4 (LTB4), a potent chemoattractant involved in the inflammatory response, but its mode of action is poorly understood.In the SHR, we observed an increase in T cells and macrophages in the brainstem; in addition, gene expression profiling data showed that LTB4 production, degradation and downstream signalling in the brainstem of the SHR are dynamically regulated during hypertension.When LTB4 receptor 1 (BLT1) receptors were blocked with CP‐105,696, arterial pressure was reduced in the SHR compared to the normotensive control and this reduction was associated with a significant decrease in systolic blood pressure (BP) indicators.These data provide new evidence for the role of LTB4 as an important neuro‐immune pathway in the development of hypertension and therefore may serve as a novel therapeutic target for the treatment of neurogenic hypertension. Abstract Accumulating evidence indicates an association between hypertension and chronic systemic inflammation in both human hypertension and experimental animal models. Previous studies in the spontaneously hypertensive rat (SHR) support a role for leukotriene B4 (LTB4), a potent chemoattractant involved in the inflammatory response. However, the mechanism for LTB4‐mediated inflammation in hypertension is poorly understood. Here we report in the SHR, increased brainstem infiltration of T cells and macrophages plus gene expression profiling data showing that LTB4 production, degradation and downstream signalling in the brainstem of the SHR are dynamically regulated during hypertension. Chronic blockade of the LTB4 receptor 1 (BLT1) receptor with CP‐105,696, reduced arterial pressure in the SHR compared to the normotensive control and this reduction was associated with a significant decrease in low and high frequency spectra of systolic blood pressure, and an increase in spontaneous baroreceptor reflex gain (sBRG). These data provide new evidence for the role of LTB4 as an important neuro‐immune pathway in the development of hypertension and therefore may serve as a novel therapeutic target for the treatment of neurogenic hypertension. PMID:27230966
Cortical dendritic activity correlates with spindle-rich oscillations during sleep in rodents.
Seibt, Julie; Richard, Clément J; Sigl-Glöckner, Johanna; Takahashi, Naoya; Kaplan, David I; Doron, Guy; de Limoges, Denis; Bocklisch, Christina; Larkum, Matthew E
2017-09-25
How sleep influences brain plasticity is not known. In particular, why certain electroencephalographic (EEG) rhythms are linked to memory consolidation is poorly understood. Calcium activity in dendrites is known to be necessary for structural plasticity changes, but this has never been carefully examined during sleep. Here, we report that calcium activity in populations of neocortical dendrites is increased and synchronised during oscillations in the spindle range in naturally sleeping rodents. Remarkably, the same relationship is not found in cell bodies of the same neurons and throughout the cortical column. Spindles during sleep have been suggested to be important for brain development and plasticity. Our results provide evidence for a physiological link of spindles in the cortex specific to dendrites, the main site of synaptic plasticity.Different stages of sleep, marked by particular electroencephalographic (EEG) signatures, have been linked to memory consolidation, but underlying mechanisms are poorly understood. Here, the authors show that dendritic calcium synchronisation correlates with spindle-rich sleep phases.
NASA Astrophysics Data System (ADS)
Overpeck, J. T.; Parsons, L. A.; Loope, G. R.; Ault, T.; Cole, J. E.; Otto-Bliesner, B. L.; Buckle, N.; Stevenson, S.; Fasullo, J.
2016-12-01
Even more than the 1930's U.S. Dust Bowl Drought, the 20th century Sahel drought stands out as the most unprecedented drought of the instrumental era, in part because it extended over multiple decades. Paleoclimatic evidence makes it clear that this Sahel drought was nonetheless not really unprecedented - droughts many decades long have occurred in sub-Saharan Africa regularly over the last several thousand years, and these constitute what is now increasingly referred to as "megadrought." Paleoclimatic evidence also makes it clear that all drought-prone semi-arid and arid regions of the globe, including southwestern North America, southeastern Australia, and the Mediterranean/Middle Eastern region likely experienced multiple such multidecadal megadroughts in recent pre-Anthropocene Earth history. In other regions of the globe, including parts of South Asia and Amazonia, short but devastating droughts of the last 50-150 years, were also eclipsed in recent Earth history by much more serious megadrought, although these megadroughts were shorter than the multidecadal droughts of Africa or SW North America. In the past, megadroughts have occurred for reasons that are increasingly well understood in terms of ocean-atmosphere dynamics that led to unusually persistent precipitation deficits. Many of these same dynamics are well simulated in state-of-the-art Earth System Models, and yet comparisons between simulated and observed paleohydroclimatic variability suggests the models generally underestimate the risk of megadrought. Paleohydroclimatic records in some cases overestimate drought persistence, but there appear to be other issues at play that need to be better understood and simulated: positive land-atmosphere feedbacks, overly energetic interannual (i.e., ENSO) modes of variability, and insufficient internal multidecadal to centennial coupled climate system variability. Taking these issues and the impact of anthropogenic climate change into account means that the risk of megadrought is increasing significantly in many regions of the globe as the planet warms - tools, including critical paleoclimatic data, are being developed to help anticipate and adapt to this growing challenge.
Making Sense of Multitasking: Key Behaviours
ERIC Educational Resources Information Center
Judd, Terry
2013-01-01
Traditionally viewed as a positive characteristic, there is mounting evidence that multitasking using digital devices can have a range of negative impacts on task performance and learning. While the cognitive processes that cause these impacts are starting to be understood and the evidence that they occur in real learning contexts is mounting, the…
Evidence synthesis and its role in evidence-based health care.
Pearson, Alan
2014-12-01
The central role of evidence synthesis (or the systematic review of evidence) in evidence-based health care is often poorly understood. There are numerous examples in the literature of poorly conceived and/or executed systematic reviews and of a lack of awareness of the international standards developed by the international leaders in systematic reviews. The Cochrane Collaboration has played a critical global role in developing and refining systematic review methods in relation to evidence of effects and of diagnostic accuracy. Copyright © 2014 Elsevier Inc. All rights reserved.
Vitamin D and adverse pregnancy outcomes: beyond bone health and growth.
Brannon, Patsy M
2012-05-01
Concerns exist about adequacy of vitamin D in pregnant women relative to both maternal and fetal adverse health outcomes. Further contributing to these concerns is the prevalence of inadequate and deficient vitamin D status in pregnant women, which ranges from 5 to 84% globally. Although maternal vitamin D metabolism changes during pregnancy, the mechanisms underlying these changes and the role of vitamin D during development are not well understood. Observational evidence links low maternal vitamin D status with an increased risk of non-bone health outcome in the mother (pre-eclampsia, gestational diabetes, obstructed labour and infectious disease), the fetus (gestational duration) and the older offspring (developmental programming of type 1 diabetes, inflammatory and atopic disorders and schizophrenia); but the totality of the evidence is contradictory (except for maternal infectious disease and offspring inflammatory and atopic disorders), lacking causality and, thus, inconclusive. In addition, recent evidence links not only low but also high maternal vitamin D status with increased risk of small-for-gestational age and schizophrenia in the offspring. Rigorous and well-designed randomised clinical trials need to determine whether vitamin D has a causal role in non-bone health outcomes in pregnancy.
Medical Judgments Across the Range of Reported Pain Severity: Clinician and Lay Perspectives.
Tait, Raymond C; Chibnall, John T; House, Kylie; Biehl, Joann
2016-07-01
While increasing evidence suggests that observers discount high-severity chronic pain, factors that occasion such discounting are poorly understood, particularly regarding health provider vs lay perspectives. This study examined the effects of supporting medical evidence and comorbid psychological distress (pain behavior) on medical student and lay clinical judgments of increasingly severe patient pain reports. In a 2 × 2 × 2 × (7) mixed between- and within-subject design, participants (medical students vs lay) made clinical judgments after reading vignettes describing a hypothetical patient that varied in levels of medical evidence and pain behavior (low vs high) and pain severity (4/10-10/10). Fourth-year medical students (N = 115) and lay persons in the community (N = 300) participated in this research. While both medical student and lay judgments plateaued at high levels of pain severity, judgments regarding cause (medical vs psychological), treatment (opioid prescription), and disability showed growing divergence as levels of reported pain severity increased. Divergence relative to medical and psychological causes of pain was found irrespective of the level of supporting medical evidence; divergence relative to opioid treatment and support for a disability claim was found when supporting medical evidence was low. The results indicate differing expectations of chronic pain treatment for health care providers relative to the lay public that could impact clinical care, especially at high pain severity levels, where lay expectations diverge significantly from those of health professionals. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Li, M.; Sloboda, D. M.; Vickers, M. H.
2011-01-01
The incidence of obesity and overweight has reached epidemic proportions in the developed world as well as in those countries transitioning to first world economies, and this represents a major global health problem. Concern is rising over the rapid increases in childhood obesity and metabolic disease that will translate into later adult obesity. Although an obesogenic nutritional environment and increasingly sedentary lifestyle contribute to our risk of developing obesity, a growing body of evidence links early life nutritional adversity to the development of long-term metabolic disorders. In particular, the increasing prevalence of maternal obesity and excess maternal weight gain has been associated with a heightened risk of obesity development in offspring in addition to an increased risk of pregnancy-related complications. The mechanisms that link maternal obesity to obesity in offspring and the level of gene-environment interactions are not well understood, but the early life environment may represent a critical window for which intervention strategies could be developed to curb the current obesity epidemic. This paper will discuss the various animal models of maternal overnutrition and their importance in our understanding of the mechanisms underlying altered obesity risk in offspring. PMID:21969822
Dimensions of Phenomenology in Exploring Patient’s Suffering in Long-Life Illnesses
Al Kalaldeh, Mahmoud; Shosha, Ghada Abu; Saiah, Najah; Salameh, Omar
2017-01-01
Background: Patients’ suffering has been increasingly investigated by health-care researchers especially in the chronically ill. Suffering is viewed as a progressive negative consequence that associated with pain, impaired self-esteem, and social alienation. This qualitative evidence synthesis aimed to provide further insights into the application of phenomenology in explaining suffering among patients with chronic illnesses. Methods: Studies included in this qualitative evidence synthesis study were retrieved by searching from the following electronic databases: CINAHL, PubMed Central, and EBSCO. Findings: Phenomenology is regarded as influential to generate in-depth evidence about suffering that are grounded in chronically ill patients’ perspectives. The philosophical constructs of suffering suggested fundamental dimensions such as stress, distress, hopelessness, and depression along with pain. Evidence encompasses the entire manifestation of suffering in which all interrelated meanings are understood and referred to a unique structure. Hermeneutic phenomenology was adopted as an effective strategy to elucidate human experience leading to the discovery of the embedded meanings of life experience. Conclusion: The phenomenological approach provides nursing research with the pathway to explore patients’ suffering experiences in the chronically ill. PMID:29582010
Onozuka, Daisuke; Hashizume, Masahiro
2011-12-01
The increasing evidence for rapid global climate change has highlighted the need for investigations examining the relationship between weather variability and infectious diseases. However, the impact of weather fluctuations on hand, foot, and mouth disease (HFMD), which primarily affects children, is not well understood. We acquired data related to cases of HFMD and weather parameters of temperature and humidity in Fukuoka, Japan between 2000 and 2010, and used time-series analyses to assess the possible relationship of weather variability with pediatric HFMD cases, adjusting for seasonal and interannual variations. Our analysis revealed that the weekly number of HFMD cases increased by 11.2% (95% CI: 3.2-19.8) for every 1°C increase in average temperature and by 4.7% (95% CI: 2.4-7.2) for every 1% increase in relative humidity. Notably, the effects of temperature and humidity on HFMD infection were most significant in children under the age of 10 years. Our study provides quantitative evidence that the number of HFMD cases increased significantly with increasing average temperature and relative humidity, and suggests that preventive measures for limiting the spread of HFMD, particularly in younger children, should be considered during extended periods of high temperature and humidity. Copyright © 2011 Elsevier B.V. All rights reserved.
Sia, Paul I; Wood, John Pm; Chidlow, Glyn; Sharma, Shiwani; Craig, Jamie; Casson, Robert J
2016-04-01
The nucleolus has emerged as a key regulator of cellular growth and the response to stress, in addition to its traditionally understood function in ribosome biogenesis. The association between nucleolar function and neurodegenerative disease is increasingly being explored. There is also recent evidence indicating that the nucleolus may well be crucial in the development of the eye. In this present review, the role of the nucleolus in retinal development as well as in neurodegeneration with an emphasis on the retina is discussed. © 2015 Royal Australian and New Zealand College of Ophthalmologists.
Rules of engagement: incomplete and complete pronoun resolution.
Love, Jessica; McKoon, Gail
2011-07-01
Research on shallow processing suggests that readers sometimes encode only a superficial representation of a text and fail to make use of all available information. Greene, McKoon, and Ratcliff (1992) extended this work to pronouns, finding evidence that readers sometimes fail to automatically identify referents even when these are unambiguous. In this paper we revisit those findings. In 11 recognition probe, priming, and self-report experiments, we manipulated Greene et al.'s stories to discover under what circumstances a pronoun's referent is automatically understood. We lengthened the stories from 4 to 8 lines. This simple manipulation led to automatic and correct resolution, which we attribute to readers' increased engagement with the stories. We found evidence of resolution even when the additional text did not mention the pronoun's referent. In addition, our results suggest that the pronoun temporarily boosts the referent's accessibility, an advantage that disappears by the end of the next sentence. Finally, we present evidence from memory experiments that supports complete pronoun resolution for the longer but not the shorter stories.
Will Culling White-Tailed Deer Prevent Lyme Disease?
Kugeler, K J; Jordan, R A; Schulze, T L; Griffith, K S; Mead, P S
2016-08-01
White-tailed deer play an important role in the ecology of Lyme disease. In the United States, where the incidence and geographic range of Lyme disease continue to increase, reduction of white-tailed deer populations has been proposed as a means of preventing human illness. The effectiveness of this politically sensitive prevention method is poorly understood. We summarize and evaluate available evidence regarding the effect of deer reduction on vector tick abundance and human disease incidence. Elimination of deer from islands and other isolated settings can have a substantial impact on the reproduction of blacklegged ticks, while reduction short of complete elimination has yielded mixed results. To date, most studies have been conducted in ecologic situations that are not representative to the vast majority of areas with high human Lyme disease risk. Robust evidence linking deer control to reduced human Lyme disease risk is lacking. Currently, there is insufficient evidence to recommend deer population reduction as a Lyme disease prevention measure, except in specific ecologic circumstances. © 2015 Blackwell Verlag GmbH.
Will Culling White-Tailed Deer Prevent Lyme Disease?
Kugeler, K. J.; Jordan, R. A.; Schulze, T. L.; Griffith, K. S.; Mead, P. S.
2015-01-01
Summary White-tailed deer play an important role in the ecology of Lyme disease. In the United States, where the incidence and geographic range of Lyme disease continue to increase, reduction of white-tailed deer populations has been proposed as a means of preventing human illness. The effectiveness of this politically sensitive prevention method is poorly understood. We summarize and evaluate available evidence regarding the effect of deer reduction on vector tick abundance and human disease incidence. Elimination of deer from islands and other isolated settings can have a substantial impact on the reproduction of blacklegged ticks, while reduction short of complete elimination has yielded mixed results. To date, most studies have been conducted in ecologic situations that are not representative to the vast majority of areas with high human Lyme disease risk. Robust evidence linking deer control to reduced human Lyme disease risk is lacking. Currently, there is insufficient evidence to recommend deer population reduction as a Lyme disease prevention measure, except in specific ecologic circumstances. PMID:26684932
Pérez, Mar; Medina, Miguel; Hernández, Félix; Avila, Jesús
2018-03-05
The microtubule-associated protein Tau plays a crucial role in stabilizing neuronal microtubules. In Tauopathies, Tau loses its ability to bind microtubules, detach from them and forms intracellular aggregates. Increasing evidence in recent years supports the notion that Tau pathology spreading throughout the brain in AD and other Tauopathies is the consequence of the propagation of specific Tau species along neuroanatomically connected brain regions in a so-called "prion-like" manner. A number of steps are assumed to be involved in this process, including secretion, cellular uptake, transcellular transfer and/or seeding, although the precise mechanisms underlying propagation of Tau pathology are not fully understood yet. This review summarizes recent evidence on the nature of the specific Tau species that are propagated and the different mechanisms of Tau pathology spreading.
Understanding Drug Use Over the Life Course: Past, Present, and Future
Hser, Yih-Ing; Hamilton, Alison; Niv, Noosha
2009-01-01
Over the past 20 years, much exciting addiction research has been conducted. Extensive knowledge has been gathered about comorbid issues, particularly mental health disorders, HIV, and criminal justice involvement. Health services addiction research has become increasingly sophisticated, shifting its focus from patients to consider also services, organizations, and financing structures. Furthermore, through several long-term follow-up studies, empirical evidence convincingly demonstrates that drug dependence is not an acute disorder, and is best understood through a life course perspective with an emphasis on chronicity This article highlights three major directions for future addiction research: developing strategies for chronic care (including longitudinal intervention studies), furthering cross-system linkage and coordination, and utilizing innovative methods (e.g., growth curve modeling, longitudinal mixed methods research) to strengthen the evidence base for the life course perspective on drug addiction. PMID:21234276
Patel, Sonny S; Rogers, M Brooke; Amlôt, Richard; Rubin, G James
2017-02-01
Government, industry and charitable organisations have an increasing focus on programs intended to support community resilience to disasters. But has consensus been reached as to what defines 'community resilience' and what its core characteristics are? We undertook a systematic literature review of definitions of community resilience related to disasters. We conducted an inductive thematic analysis of the definitions and descriptions that we identified, in order to determine the proposed characteristics of community resilience prior to, during and after a disaster. We identified 80 relevant papers. There was no evidence of a common, agreed definition of community resilience. In spite of this, evidence was found of nine core elements of community resilience that were common among the definitions. The core elements were: local knowledge, community networks and relationships, communication, health, governance and leadership, resources, economic investment, preparedness, and mental outlook. Within these core elements, we identified 19 sub-elements linked to community resilience. Our findings show that community resilience remains an amorphous concept that is understood and applied differently by different research groups. Yet in spite of the differences in conception and application, there are well-understood elements that are widely proposed as important for a resilient community. A focus on these individual elements may be more productive than attempting to define and study community resilience as a distinct concept.
Patel, Sonny S.; Rogers, M. Brooke; Amlôt, Richard; Rubin, G. James
2017-01-01
Background: Government, industry and charitable organisations have an increasing focus on programs intended to support community resilience to disasters. But has consensus been reached as to what defines 'community resilience' and what its core characteristics are? Methods: We undertook a systematic literature review of definitions of community resilience related to disasters. We conducted an inductive thematic analysis of the definitions and descriptions that we identified, in order to determine the proposed characteristics of community resilience prior to, during and after a disaster. Results: We identified 80 relevant papers. There was no evidence of a common, agreed definition of community resilience. In spite of this, evidence was found of nine core elements of community resilience that were common among the definitions. The core elements were: local knowledge, community networks and relationships, communication, health, governance and leadership, resources, economic investment, preparedness, and mental outlook. Within these core elements, we identified 19 sub-elements linked to community resilience. Conclusion: Our findings show that community resilience remains an amorphous concept that is understood and applied differently by different research groups. Yet in spite of the differences in conception and application, there are well-understood elements that are widely proposed as important for a resilient community. A focus on these individual elements may be more productive than attempting to define and study community resilience as a distinct concept. PMID:29188132
Prebiotics in Companion and Livestock Animal Nutrition
NASA Astrophysics Data System (ADS)
Barry, Kathleen A.; Vester, Brittany M.; Fahey, George C.
Prebiotic supplementation of animal diets began in an attempt to increase concentrations of beneficial intestinal microbiota. It was understood that prebiotics inhibited growth of intestinal pathogens and decreased concentrations of stool odor-causing metabolites. Since the use of prebiotics began, several countries have banned the use of antimicrobials in livestock animal feeds, and several more have placed restrictions on the quantity of antimicrobials that can be used. Prebiotic supplementation has become increasingly popular as the body of evidence supporting its use continues to grow. As this literature expands, the number of potential prebiotic substances has grown beyond those that are naturally occurring, such as those found in chicory and yeast products, to include a large number of synthetic or chemically/enzymatically manufactured prebiotics.
Mindful Intuition: An Effective Leadership Response to the Community College Environment
ERIC Educational Resources Information Center
Ryslinge, Birgitte
2009-01-01
Despite evidence of widespread reliance on intuition by leaders and evidence that consequences of such reliance can be positive or negative, the effective integration of intuition in leadership is not well understood. This constructivist grounded theory study explored how some leaders in California community colleges (CC) experienced intuition and…
Common pitfalls in statistical analysis: “No evidence of effect” versus “evidence of no effect”
Ranganathan, Priya; Pramesh, C. S.; Buyse, Marc
2015-01-01
This article is the first in a series exploring common pitfalls in statistical analysis in biomedical research. The power of a clinical trial is the ability to find a difference between treatments, where such a difference exists. At the end of the study, the lack of difference between treatments does not mean that the treatments can be considered equivalent. The distinction between “no evidence of effect” and “evidence of no effect” needs to be understood. PMID:25657905
Foamed emulsion drainage: flow and trapping of drops.
Schneider, Maxime; Zou, Ziqiang; Langevin, Dominique; Salonen, Anniina
2017-06-07
Foamed emulsions are ubiquitous in our daily life but the ageing of such systems is still poorly understood. In this study we investigate foam drainage and measure the evolution of the gas, liquid and oil volume fractions inside the foam. We evidence three regimes of ageing. During an initial period of fast drainage, both bubbles and drops are very mobile. As the foam stabilises drainage proceeds leading to a gradual decrease of the liquid fraction and slowing down of drainage. Clusters of oil drops are less sheared, their dynamic viscosity increases and drainage slows down even further, until the drops become blocked. At this point the oil fraction starts to increase in the continuous phase. The foam ageing leads to an increase of the capillary pressure until the oil acts as an antifoaming agent and the foam collapses.
Maenner, Matthew J; Greenberg, Jan S; Mailick, Marsha R
2016-01-01
Lower (versus higher) IQ scores have been shown to increase the risk of early mortality, however, the underlying mechanisms are poorly understood and previous studies underrepresent individuals with intellectual disabilities and women. This study followed one-third of all senior-year students (approximately aged 17) attending public high school in Wisconsin, USA in 1957 (n=10,317) until 2011. Men and women with mild intellectual disabilities had increased rates of mortality compared to people with the highest IQs, particularly for cardiovascular disease. Importantly, when educational attainment was held constant, people with intellectual disabilities did not have higher mortality by age 70 than people with higher IQs. Individuals with intellectual disabilities likely experience multiple disadvantages throughout life that contribute to increased risk of early mortality. PMID:25928436
ERIC Educational Resources Information Center
Fergusson, David M.; Boden, Joseph M.; Horwood, L. John
2009-01-01
Background: There is considerable evidence suggesting that many children show conduct problems that are specific to a given context (home; school). What is less well understood is the extent to which children with situation-specific conduct problems show similar outcomes to those with generalised conduct problems. Methods: Data were gathered as…
ERIC Educational Resources Information Center
Jobes, David A.
2012-01-01
The Collaborative Assessment and Management of Suicidality (CAMS) is an evidence-based clinical intervention that has significantly evolved over 25 years of clinical research. CAMS is best understood as a therapeutic framework that emphasizes a unique collaborative assessment and treatment planning process between the suicidal patient and…
Autism spectrum disorder in children born preterm—role of exposure to perinatal inflammation
Meldrum, Suzanne J.; Strunk, T.; Currie, A.; Prescott, S. L.; Simmer, K.; Whitehouse, A. J. O.
2013-01-01
Autism Spectrum Disorder (ASD) is the collective term for neurodevelopmental disorders characterized by qualitative impairments in social interaction, communication, and a restricted range of activities and interests. Many countries, including Australia, have reported a dramatic increase in the number of diagnoses over the past three decades, with current prevalence of ASD at 1 in every 110 individuals (~1%). The potential role for an immune-mediated mechanism in ASD has been implicated by several studies, and some evidence suggests a potential link between prenatal infection-driven inflammation and subsequent development of ASD. Furthermore, a modest number of contemporary studies have reported a markedly increased prevalence of ASD in children born preterm, who are at highest risk of exposure to perinatal inflammation. However, the mechanisms that underpin the susceptibility to infection-driven inflammation during pregnancy and risk of preterm birth, and how these intersect with the subsequent development of ASD in the offspring, is not understood. This review aims to summarize and discuss the potential mechanisms and evidence for the role of prenatal infection on the central nervous system, and how it may increase the susceptibility for ASD pathogenesis in children born preterm. PMID:23885233
Pulmonary Hypertension in Bronchopulmonary Dysplasia
Berkelhamer, Sara K.; Mestan, Karen K.; Steinhorn, Robin H.
2013-01-01
Pulmonary hypertension (PH) is a common complication of neonatal respiratory diseases including bronchopulmonary dysplasia (BPD), and recent studies have increased awareness that PH worsens the clinical course, morbidity and mortality of BPD. Recent evidence indicates that up to 18% of all extremely low birth weight infants will develop some degree of PH during their hospitalization, and the incidence rises to 25–40% of infants with established BPD. Risk factors are not yet well understood, but new evidence shows that fetal growth restriction is a significant predictor of PH. Echocardiography remains the primary method for evaluation for BPD-associated PH, and the development of standardized screening timelines and techniques for identification of infants with BPD-associated PH remains an important ongoing topic of investigation. The use of pulmonary vasodilator medications such as nitric oxide, sildenafil, and others in the BPD population is steadily growing, but additional studies are needed regarding their long-term safety and efficacy. PMID:23582967
Observational evidence for cloud cover enhancement over western European forests.
Teuling, Adriaan J; Taylor, Christopher M; Meirink, Jan Fokke; Melsen, Lieke A; Miralles, Diego G; van Heerwaarden, Chiel C; Vautard, Robert; Stegehuis, Annemiek I; Nabuurs, Gert-Jan; de Arellano, Jordi Vilà-Guerau
2017-01-11
Forests impact regional hydrology and climate directly by regulating water and heat fluxes. Indirect effects through cloud formation and precipitation can be important in facilitating continental-scale moisture recycling but are poorly understood at regional scales. In particular, the impact of temperate forest on clouds is largely unknown. Here we provide observational evidence for a strong increase in cloud cover over large forest regions in western Europe based on analysis of 10 years of 15 min resolution data from geostationary satellites. In addition, we show that widespread windthrow by cyclone Klaus in the Landes forest led to a significant decrease in local cloud cover in subsequent years. Strong cloud development along the downwind edges of larger forest areas are consistent with a forest-breeze mesoscale circulation. Our results highlight the need to include impacts on cloud formation when evaluating the water and climate services of temperate forests, in particular around densely populated areas.
Observational evidence for cloud cover enhancement over western European forests
Teuling, Adriaan J.; Taylor, Christopher M.; Meirink, Jan Fokke; Melsen, Lieke A.; Miralles, Diego G.; van Heerwaarden, Chiel C.; Vautard, Robert; Stegehuis, Annemiek I.; Nabuurs, Gert-Jan; de Arellano, Jordi Vilà-Guerau
2017-01-01
Forests impact regional hydrology and climate directly by regulating water and heat fluxes. Indirect effects through cloud formation and precipitation can be important in facilitating continental-scale moisture recycling but are poorly understood at regional scales. In particular, the impact of temperate forest on clouds is largely unknown. Here we provide observational evidence for a strong increase in cloud cover over large forest regions in western Europe based on analysis of 10 years of 15 min resolution data from geostationary satellites. In addition, we show that widespread windthrow by cyclone Klaus in the Landes forest led to a significant decrease in local cloud cover in subsequent years. Strong cloud development along the downwind edges of larger forest areas are consistent with a forest-breeze mesoscale circulation. Our results highlight the need to include impacts on cloud formation when evaluating the water and climate services of temperate forests, in particular around densely populated areas. PMID:28074840
Learning Collaboratives: Insights And A New Taxonomy From AHRQ's Two Decades Of Experience.
Nix, Mary; McNamara, Peggy; Genevro, Janice; Vargas, Natalia; Mistry, Kamila; Fournier, Alaina; Shofer, Margie; Lomotan, Edwin; Miller, Therese; Ricciardi, Richard; Bierman, Arlene S
2018-02-01
Learning collaboratives are increasingly used as mechanisms to support and hasten the diffusion and implementation of innovation, clinical evidence, and effective models of care. Factors contributing to the collaboratives' success or failure are poorly understood. The Agency for Healthcare Research and Quality (AHRQ) has sponsored collaboratives for nearly two decades to support improvements in health care quality and value by accelerating the diffusion and implementation of innovation. We examined AHRQ's experience with these collaboratives to characterize their attributes, identify factors that might contribute to their success or failure, and assess the challenges they encountered. Building on the literature and insights from AHRQ's experience, we propose a taxonomy that can offer guidance to decision makers and funders about the factors they should consider in developing collaboratives and planning their evaluation, as well as to researchers who seek to conduct research that will ultimately help decision makers make better investments in diffusing innovation and evidence.
Ashok, A H; Marques, T R; Jauhar, S; Nour, M M; Goodwin, G M; Young, A H; Howes, O D
2017-01-01
Bipolar affective disorder is a common neuropsychiatric disorder. Although its neurobiological underpinnings are incompletely understood, the dopamine hypothesis has been a key theory of the pathophysiology of both manic and depressive phases of the illness for over four decades. The increased use of antidopaminergics in the treatment of this disorder and new in vivo neuroimaging and post-mortem studies makes it timely to review this theory. To do this, we conducted a systematic search for post-mortem, pharmacological, functional magnetic resonance and molecular imaging studies of dopamine function in bipolar disorder. Converging findings from pharmacological and imaging studies support the hypothesis that a state of hyperdopaminergia, specifically elevations in D2/3 receptor availability and a hyperactive reward processing network, underlies mania. In bipolar depression imaging studies show increased dopamine transporter levels, but changes in other aspects of dopaminergic function are inconsistent. Puzzlingly, pharmacological evidence shows that both dopamine agonists and antidopaminergics can improve bipolar depressive symptoms and perhaps actions at other receptors may reconcile these findings. Tentatively, this evidence suggests a model where an elevation in striatal D2/3 receptor availability would lead to increased dopaminergic neurotransmission and mania, whilst increased striatal dopamine transporter (DAT) levels would lead to reduced dopaminergic function and depression. Thus, it can be speculated that a failure of dopamine receptor and transporter homoeostasis might underlie the pathophysiology of this disorder. The limitations of this model include its reliance on pharmacological evidence, as these studies could potentially affect other monoamines, and the scarcity of imaging evidence on dopaminergic function. This model, if confirmed, has implications for developing new treatment strategies such as reducing the dopamine synthesis and/or release in mania and DAT blockade in bipolar depression. PMID:28289283
Patient safety in anesthesia: learning from the culture of high-reliability organizations.
Wright, Suzanne M
2015-03-01
There has been an increased awareness of and interest in patient safety and improved outcomes, as well as a growing body of evidence substantiating medical error as a leading cause of death and injury in the United States. According to The Joint Commission, US hospitals demonstrate improvements in health care quality and patient safety. Although this progress is encouraging, much room for improvement remains. High-reliability organizations, industries that deliver reliable performances in the face of complex working environments, can serve as models of safety for our health care system until plausible explanations for patient harm are better understood. Copyright © 2015 Elsevier Inc. All rights reserved.
Developing guidelines in low-income and middle-income countries: lessons from Kenya
English, Mike; Irimu, Grace; Nyamai, Rachel; Were, Fred; Garner, Paul; Opiyo, Newton
2017-01-01
There are few examples of sustained nationally organised, evidence-informed clinical guidelines development processes in Sub-Saharan Africa. We describe the evolution of efforts from 2005 to 2015 to support evidence-informed decision making to guide admission hospital care practices in Kenya. The approach to conduct reviews, present evidence, and structure and promote transparency of consensus-based procedures for making recommendations improved over four distinct rounds of policy making. Efforts to engage important voices extended from government and academia initially to include multiple professional associations, regulators and practitioners. More than 100 people have been engaged in the decision-making process; an increasing number outside the research team has contributed to the conduct of systematic reviews, and 31 clinical policy recommendations has been developed. Recommendations were incorporated into clinical guideline booklets that have been widely disseminated with a popular knowledge and skills training course. Both helped translate evidence into practice. We contend that these efforts have helped improve the use of evidence to inform policy. The systematic reviews, Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approaches and evidence to decision-making process are well understood by clinicians, and the process has helped create a broad community engaged in evidence translation together with a social or professional norm to use evidence in paediatric care in Kenya. Specific sustained efforts should be made to support capacity and evidence-based decision making in other African settings and clinical disciplines. PMID:28584069
A Critical Look at Prebiotics Within the Dietary Fiber Concept.
Verspreet, Joran; Damen, Bram; Broekaert, Willem F; Verbeke, Kristin; Delcour, Jan A; Courtin, Christophe M
2016-01-01
This article reviews the current knowledge of the health effects of dietary fiber and prebiotics and establishes the position of prebiotics within the broader context of dietary fiber. Although the positive health effects of specific fibers on defecation, reduction of postprandial glycemic response, and maintenance of normal blood cholesterol levels are generally accepted, other presumed health benefits of dietary fibers are still debated. There is evidence that specific dietary fibers improve the integrity of the epithelial layer of the intestines, increase the resistance against pathogenic colonization, reduce the risk of developing colorectal cancer, increase mineral absorption, and have a positive impact on the immune system, but these effects are neither generally acknowledged nor completely understood. Many of the latter effects are thought to be particularly elicited by prebiotics. Although the prebiotic concept evolved significantly during the past two decades, the line between prebiotics and nonprebiotic dietary fiber remains vague. Nevertheless, scientific evidence demonstrating the health-promoting potential of prebiotics continues to accumulate and suggests that prebiotic fibers have their rightful place in a healthy diet.
NASA Astrophysics Data System (ADS)
Lee, Sung Keun; Park, Sun Young; Kim, Hyo-Im; Tschauner, Oliver; Asimow, Paul; Bai, Ligang; Xiao, Yuming; Chow, Paul
2012-03-01
The detailed atomic structures of shock compressed basaltic glasses are not well understood. Here, we explore the structures of shock compressed silicate glass with a diopside-anorthite eutectic composition (Di64An36), a common Fe-free model basaltic composition, using oxygen K-edge X-ray Raman scattering and high- resolution 27Al solid-state NMR spectroscopy and report previously unknown details of shock-induced changes in the atomic configurations. A topologically driven densification of the Di64An36 glass is indicated by the increase in oxygen K-edge energy for the glass upon shock compression. The first experimental evidence of the increase in the fraction of highly coordinated Al in shock compressed glass is found in the 27Al NMR spectra. This unambiguous evidence of shock-induced changes in Al coordination environments provides atomistic insights into shock compression in basaltic glasses and allows us to microscopically constrain the magnitude of impact events or relevant processes involving natural basalts on Earth and planetary surfaces.
Sleep and metabolism: role of hypothalamic neuronal circuitry.
Rolls, Asya; Schaich Borg, Jana; de Lecea, Luis
2010-10-01
Sleep and metabolism are intertwined physiologically and behaviorally, but the neural systems underlying their coordination are still poorly understood. The hypothalamus is likely to play a major role in the regulation sleep, metabolism, and their interaction. And increasing evidence suggests that hypocretin cells in the lateral hypothalamus may provide particularly important contributions. Here we review: 1) direct interactions between biological arousal and metabolic systems in the hypothalamus, and 2) indirect interactions between these two systems mediated by stress or reward, emphasizing the role of hypocretins. An increased understanding of the mechanisms underlying these interactions may provide novel approaches for the treatment of patients with sleep disorders and obesity, as well as suggest new therapeutic strategies for symptoms of aging, stress, or addiction. Copyright © 2010. Published by Elsevier Ltd.
Convergent evidence for mGluR5 in synaptic and neuroinflammatory pathways implicated in ASD.
Zantomio, Daniela; Chana, Gursharan; Laskaris, Liliana; Testa, Renee; Everall, Ian; Pantelis, Christos; Skafidas, Efstratios
2015-05-01
The pathogenesis of Autism Spectrum Disorder (ASD), a serious neurodevelopmental disorder, is poorly understood. We review evidence for alterations in glutamatergic signalling in the aetiology of ASD, with a focus on the metabotropic glutamate receptor-5 (mGluR5). mGluR5 signalling is important for synapse formation, neuroplasticity and long term potentiation as well as neuroprotection and has been shown to have a regulatory role in neuroinflammation. Evidence for neuroinflammation in ASD is supported by increase in pro-inflammatory cytokines in the blood and cerebrospinal fluid (CSF) and increased number and activation of microglia in postmortem dorsolateral prefrontal cortex (DLPFC). mGlur5 signalling has also been shown to downregulate microglial activation. Therefore, we focus on mGluR5 as a potential unifying explanation for synapse alteration and neuroinflammation seen in ASD. Data from mGluR5 knockout mouse models, and syndromic and non syndromic forms of ASD are discussed in relation to how alterations in mGluR5 are associated with ASD symptoms. This review supports altered mGluR5 functioning as a convergent point in ASD pathogenesis and indicates more research is warranted into mGluR5 as a potential therapeutic target. Copyright © 2015 Elsevier Ltd. All rights reserved.
Air pollution during pregnancy and lung development in the child.
Korten, Insa; Ramsey, Kathryn; Latzin, Philipp
2017-01-01
Air pollution exposure has increased extensively in recent years and there is considerable evidence that exposure to particulate matter can lead to adverse respiratory outcomes. The health impacts of exposure to air pollution during the prenatal period is especially concerning as it can impair organogenesis and organ development, which can lead to long-term complications. Exposure to air pollution during pregnancy affects respiratory health in different ways. Lung development might be impaired by air pollution indirectly by causing lower birth weight, premature birth or disturbed development of the immune system. Exposure to air pollution during pregnancy has also been linked to decreased lung function in infancy and childhood, increased respiratory symptoms, and the development of childhood asthma. In addition, impaired lung development contributes to infant mortality. The mechanisms of how prenatal air pollution affects the lungs are not fully understood, but likely involve interplay of environmental and epigenetic effects. The current epidemiological evidence on the effect of air pollution during pregnancy on lung function and children's respiratory health is summarized in this review. While evidence for the adverse effects of prenatal air pollution on lung development and health continue to mount, rigorous actions must be taken to reduce air pollution exposure and thus long-term respiratory morbidity and mortality. Copyright © 2016 Elsevier Ltd. All rights reserved.
Evidence, research, knowledge: a call for conceptual clarity.
Scott-Findlay, Shannon; Pollock, Carolee
2004-01-01
To dispel some of the conceptual confusion in the field of evidence-based practice that has resulted from the overlapping use of the terms research, evidence, and knowledge. Theoretical discussion. Often the terms research and knowledge are used as synonyms for evidence, but the overlap is never complete. The term evidence has long been understood to mean the findings of research. Recent attempts to broaden the definition of evidence to include clinical experience and experiential knowledge have been misguided. Broadening our understanding of the basis for clinical decision making and conceptualizing evidence are quite different tasks. Other factors (not other forms of evidence) do shape the clinical decision-making process, but they are not evidence. We might better term them knowledge. Confusing evidence with these other factors has hindered research and the improvement of clinical decision making in health care. We argue that this confusion results from the use of the term evidence when we really mean either research findings or knowledge. In this article, we have argued for specificity in the use of the term evidence. We urge the restriction of the term evidence to research findings, and while we acknowledge the importance of other influences on the clinical decision-making process, we insist that they are not evidence. The time has come to value personal experience and experiential knowledge for what they are-we should not have to disguise them as types of evidence for them to be deemed of any value. Being specific to language, the goal is to improve clinical decision making by increasing practitioners' reliance on research findings (evidence) while acknowledging (and valuing) the important part played by other forms of knowledge in the decision-making process. The distinctions are important.
Acute clinical recovery from sport-related concussion.
Nelson, Lindsay D; Janecek, Julie K; McCrea, Michael A
2013-12-01
Concussion is a highly prevalent injury in contact and collision sports that has historically been poorly understood. An influx of sport-concussion research in recent years has led to a dramatic improvement in our understanding of the injury's defining characteristics and natural history of recovery. In this review, we discuss the current state of knowledge regarding the characteristic features of concussion and typical acute course of recovery, with an emphasis on the aspects of functioning most commonly assessed by clinicians and researchers (e.g., symptoms, cognitive deficits, postural stability). While prototypical clinical recovery is becoming better understood, questions remain regarding what factors (e.g., injury severity, demographic variables, history of prior concussions, psychological factors) may explain individual variability in recovery. Although research concerning individual differences in response to concussion is relatively new, and in many cases limited methodologically, we discuss the evidence about several potential moderators of concussion recovery and point out areas for future research. Finally, we describe how increased knowledge about the negative effects of and recovery following concussion has been translated into clinical guidelines for managing concussed athletes.
Jack, Susan M; Brooks, Sandy; Furgal, Chris M; Dobbins, Maureen
2010-02-01
Within Canadian Aboriginal communities, the process for utilizing environmental health research evidence in the development of policies and programs is not well understood. This fundamental qualitative descriptive study explored the perceptions of 28 environmental health researchers, senior external decision-makers and decision-makers working within Aboriginal communities about factors influencing knowledge transfer and exchange, beliefs about research evidence and Traditional Knowledge and the preferred communication channels for disseminating and receiving evidence. The results indicate that collaborative relationships between researchers and decision-makers, initiated early and maintained throughout a research project, promote both the efficient conduct of a study and increase the likelihood of knowledge transfer and exchange. Participants identified that empirical research findings and Traditional Knowledge are different and distinct types of evidence that should be equally valued and used where possible to provide a holistic understanding of environmental issues and support decisions in Aboriginal communities. To facilitate the dissemination of research findings within Aboriginal communities, participants described the elements required for successfully crafting key messages, locating and using credible messengers to deliver the messages, strategies for using cultural brokers and identifying the communication channels commonly used to disseminate and receive this type of information.
Jack, Susan M.; Brooks, Sandy; Furgal, Chris M.; Dobbins, Maureen
2010-01-01
Within Canadian Aboriginal communities, the process for utilizing environmental health research evidence in the development of policies and programs is not well understood. This fundamental qualitative descriptive study explored the perceptions of 28 environmental health researchers, senior external decision-makers and decision-makers working within Aboriginal communities about factors influencing knowledge transfer and exchange, beliefs about research evidence and Traditional Knowledge and the preferred communication channels for disseminating and receiving evidence. The results indicate that collaborative relationships between researchers and decision-makers, initiated early and maintained throughout a research project, promote both the efficient conduct of a study and increase the likelihood of knowledge transfer and exchange. Participants identified that empirical research findings and Traditional Knowledge are different and distinct types of evidence that should be equally valued and used where possible to provide a holistic understanding of environmental issues and support decisions in Aboriginal communities. To facilitate the dissemination of research findings within Aboriginal communities, participants described the elements required for successfully crafting key messages, locating and using credible messengers to deliver the messages, strategies for using cultural brokers and identifying the communication channels commonly used to disseminate and receive this type of information. PMID:20616996
The significance of the effect of stand density upon the weather beneath the canopy
G. M. Jemison
1934-01-01
During the middle of the nineteenth century forests were believed to have important influences on climate. As climate was more thoroughly understood it became evident that the major climatic controls were beyond the influence of forest cover, a finding which wholly discredited the earlier conclusions. It was evident to the forester and student of ecology, however, that...
Florentino B. De la Cruz; Daniel J. Yelle; Hanna S. Gracz; Morton A. Barlaz
2014-01-01
The anaerobic decomposition of plant biomass is an important aspect of global organic carbon cycling. While the anaerobic metabolism of cellulose and hemicelluloses to methane and carbon dioxide are well-understood, evidence for the initial stages of lignin decomposition is fragmentary. The objective of this study was to look for evidence of chemical transformations of...
ERIC Educational Resources Information Center
Archer, Louise; Francis, Becky; Miller, Sarah; Taylor, Becky; Tereshchenko, Antonina; Mazenod, Anna; Pepper, David; Travers, Mary-Claire
2018-01-01
"Setting" is a widespread practice in the UK, despite little evidence of its efficacy and substantial evidence of its detrimental impact on those allocated to the lowest sets. Taking a Bourdieusian approach, we propose that setting can be understood as a practice through which the social and cultural reproduction of dominant power…
Maenner, Matthew J; Greenberg, Jan S; Mailick, Marsha R
2015-05-01
Lower (versus higher) IQ scores have been shown to increase the risk of early mortality, however, the underlying mechanisms are poorly understood and previous studies underrepresent individuals with intellectual disability (ID) and women. This study followed one third of all senior-year students (approximately aged 17) attending public high school in Wisconsin, U.S. in 1957 (n = 10,317) until 2011. Men and women with the lowest IQ test scores (i.e., IQ scores ≤ 85) had increased rates of mortality compared to people with the highest IQ test scores, particularly for cardiovascular disease. Importantly, when educational attainment was held constant, people with lower IQ test scores did not have higher mortality by age 70 than people with higher IQ test scores. Individuals with lower IQ test scores likely experience multiple disadvantages throughout life that contribute to increased risk of early mortality.
Thermostability in rubredoxin and its relationship to mechanical rigidity
NASA Astrophysics Data System (ADS)
Rader, A. J.
2010-03-01
The source of increased stability in proteins from organisms that thrive in extreme thermal environments is not well understood. Previous experimental and theoretical studies have suggested many different features possibly responsible for such thermostability. Many of these thermostabilizing mechanisms can be accounted for in terms of structural rigidity. Thus a plausible hypothesis accounting for this remarkable stability in thermophilic enzymes states that these enzymes have enhanced conformational rigidity at temperatures below their native, functioning temperature. Experimental evidence exists to both support and contradict this supposition. We computationally investigate the relationship between thermostability and rigidity using rubredoxin as a case study. The mechanical rigidity is calculated using atomic models of homologous rubredoxin structures from the hyperthermophile Pyrococcus furiosus and mesophile Clostridium pasteurianum using the FIRST software. A global increase in structural rigidity (equivalently a decrease in flexibility) corresponds to an increase in thermostability. Locally, rigidity differences (between mesophilic and thermophilic structures) agree with differences in protection factors.
Inflammation and angiogenesis in fibrotic lung disease.
Keane, Michael P; Strieter, Robert M; Lynch, Joseph P; Belperio, John A
2006-12-01
The pathogenesis of pulmonary fibrosis is poorly understood. Although inflammation has been presumed to have an important role in the development of fibrosis this has been questioned recently, particularly with regard to idiopathic pulmonary fibrosis (IPF). It is, however, increasingly recognized that the polarization of the inflammatory response toward a type 2 phenotype supports fibroproliferation. Increased attention has been on the role of noninflammatory structural cells such as the fibroblast, myofibroblast, epithelial cell, and endothelial cells. Furthermore, the origin of these cells appears to be multifactorial and includes resident cells, bone marrow-derived cells, and epithelial to mesenchymal transition. Increasing evidence supports the presence of vascular remodeling in fibrotic lung disease, although the precise role in the pathogenesis of fibrosis remains to be determined. Therefore, the pathogenesis of pulmonary fibrosis is complex and involves the interaction of multiple cell types and compartments within the lung.
Rules of Engagement: Incomplete and Complete Pronoun Resolution
Love, Jessica; McKoon, Gail
2011-01-01
Research on shallow processing suggests that readers sometimes encode only a superficial representation of a text, failing to make use of all available information. Greene, McKoon and Ratcliff (1992) extended this work to pronouns, finding evidence that readers sometimes fail to automatically identify referents even when they are unambiguous. In this paper we revisit those findings. In 11 recognition probe, priming, and self-report experiments, we manipulated Greene et al.’s stories to discover under what circumstances a pronoun’s referent is automatically understood. We lengthened the stories from four to eight lines, a simple manipulation that led to automatic and correct resolution, which we attribute to readers’ increased engagement with the stories. We found evidence of resolution even when the additional text did not mention the pronoun’s referent. In addition, our results suggest that the pronoun temporarily boosts the referent’s accessibility, an advantage that disappears by the end of the next sentence. Finally, we present evidence from memory experiments that support complete pronoun resolution for the longer, but not the shorter, stories. PMID:21480757
Sex Differences in the Biology and Pathology of the Aging Heart.
Keller, Kaitlyn M; Howlett, Susan E
2016-09-01
The knowledge that advanced age is a major risk factor for cardiovascular disease (CVD) has stimulated interest in cardiac aging. Understanding how the heart remodels with age can help us appreciate why older individuals are more likely to acquire heart disease. Growing evidence in both humans and animals shows that the heart exhibits distinct structural and functional changes as a consequence of age. These changes occur even in the absence of overt cardiovascular disease and are often maladaptive. For example, atrial hypertrophy and fibrosis may increase susceptibility to atrial fibrillation in older adults. Age-dependent increases in left ventricular fibrosis, stiffness, and wall thickness promote diastolic dysfunction, predisposing to heart failure with preserved ejection fraction. The influence of age on the heart is evident at rest but is even more prominent during exercise. There is also evidence for sex-specific variation in age-associated remodelling. For instance, there is some evidence that the number of ventricular myocytes declines with age through apoptosis in men but not in women. This helps explain why older men are more likely than women to experience heart failure with reduced ejection fraction. Emerging evidence from preclinical studies suggests that frailty rather than chronological age promotes adverse cardiac remodelling. Mechanisms implicated in cardiac aging include impaired calcium handling, excessive activation of the ß-adrenergic and renin-angiotensin systems, and mitochondrial dysfunction. Further research into cardiac aging in both sexes is needed, because it may be possible to modify disease treatment if the substrate upon which the disease first develops is better understood. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
2007-09-01
mechanisms and genetic pathways involved in the pathogenesis of myeloproliferative disease (MPDs) are not well understood. Telomere maintenance and...24). A large body of evidence demonstrates the importance of tyrosine kinase mutations to the development of myeloproliferative disorders
Pigment-Dispersing Factor Signaling and Circadian Rhythms in Insect Locomotor Activity
Shafer, Orie T.; Yao, Zepeng
2014-01-01
Though expressed in relatively few neurons in insect nervous systems, pigment-dispersing factor (PDF) plays many roles in the control of behavior and physiology. PDF’s role in circadian timekeeping is its best-understood function and the focus of this review. Here we recount the isolation and characterization of insect PDFs, review the evidence that PDF acts as a circadian clock output factor, and discuss emerging models of how PDF functions within circadian clock neuron network of Drosophila, the species in which this peptide’s circadian roles are best understood. PMID:25386391
A Review on the Role of Inflammation in Attention-Deficit/Hyperactivity Disorder.
Leffa, Douglas Teixeira; Torres, Iraci L S; Rohde, Luis Augusto
2018-06-06
Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental condition that impairs quality of life in social, academic, and occupational contexts for both children and adults. Although a strong neurobiological basis has been demonstrated, the pathophysiology of ADHD is still poorly understood. Among the proposed mechanisms are glial activation, neuronal damage and degeneration, increased oxidative stress, reduced neurotrophic support, altered neurotransmitter metabolism, and blood-brain barrier disruption. In this way, a potential role of inflammation has been increasingly researched. However, evidence for the involvement of inflammation in ADHD is still scarce and comes mainly from (1) observational studies showing a strong comorbidity of ADHD with inflammatory and autoimmune disorders; (2) studies evaluating serum inflammatory markers; and (3) genetic studies. A co-occurrence of ADHD with inflammatory disorders has been demonstrated in a large number of subjects, suggesting a range of underlying mechanisms such as an altered immune response, common genetics, and environmental links. The evaluation of serum inflammatory markers has provided mixed results, likely due to the small sample sizes and high heterogeneity between biomarkers. However, there is evidence that increased inflammation during the early development may be a risk factor for ADHD symptoms. Although genetic studies have demonstrated a potential role for inflammation in this disorder, there is no clear evidence. To sum up, inflammation may be an important mechanism in ADHD pathophysiology, but more studies are still needed for a more precise conclusion. © 2018 S. Karger AG, Basel.
Bacterial sulfur disproportionation constrains timing of neoproterozoic oxygenation
Kunzmann, Marcus; Bui, Thi Hao; Crockford, Peter W.; Halverson, Galen P.; Scott, Clinton T.; Lyons, Timothy W.; Wing, Boswell A.
2017-01-01
Various geochemical records suggest that atmospheric O2 increased in the Ediacaran (635–541 Ma), broadly coincident with the emergence and diversification of large animals and increasing marine ecosystem complexity. Furthermore, geochemical proxies indicate that seawater sulfate levels rose at this time too, which has been hypothesized to reflect increased sulfide oxidation in marine sediments caused by sediment mixing of the newly evolved macrofauna. However, the exact timing of oxygenation is not yet understood, and there are claims for significant oxygenation prior to the Ediacaran. Furthermore, recent evidence suggests that physical mixing of sediments did not become important until the late Silurian. Here we report a multiple sulfur isotope record from a ca. 835–630 Ma succession from Svalbard, further supported by data from Proterozoic strata in Canada, Australia, Russia, and the United States, in order to investigate the timing of oxygenation. We present isotopic evidence for onset of globally significant bacterial sulfur disproportionation and reoxidative sulfur cycling following the 635 Ma Marinoan glaciation. Widespread sulfide oxidation helps to explain the observed first-order increase in seawater sulfate concentration from the earliest Ediacaran to the Precambrian-Cambrian boundary by reducing the amount of sulfur buried as pyrite. Expansion of reoxidative sulfur cycling to a global scale also indicates increasing environmental O2 levels. Thus, our data suggest that increasing atmospheric O2 levels may have played a role in the emergence of the Ediacaran macrofauna and increasing marine ecosystem complexity.
De Waele, Jan J
2016-08-01
Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy.
Dry mouth: Xerostomia and salivary gland hypofunction.
Frydrych, Agnieszka M
2016-07-01
Mouth dryness may present as salivary gland hypofunction (SGH), xerostomia or both. It is considered one of the most underappreciated, underdiagnosed and undermanaged oral health conditions. Despite its common presentation and adverse impact on life quality, it is also generally poorly understood. Increased awareness of the condition is important in addressing these problems. This article discusses SGH and xerostomia, and the associated intra-oral and extra-oral implications. It also summarises currently available management approaches and the evidence behind them. SGH and xerostomia are complex problems. None of the currently available management approaches are entirely satisfactory. Addressing the causative or contributing factors is therefore paramount. While oral health complaints are generally left up to the dental professional to manage, the nature of mouth dryness necessitates increased dialogue between the dental and medical professions to ensure optimal patient care.
Nutrient enrichment enhances black band disease progression in corals
NASA Astrophysics Data System (ADS)
Voss, Joshua D.; Richardson, Laurie L.
2006-11-01
Infectious diseases are recognized as significant contributors to the dramatic loss of corals observed worldwide. However, the causes of increased coral disease prevalence and severity are not well understood. One potential factor is elevated nutrient concentration related to localized anthropogenic activities such as inadequate waste water treatment or terrestrial runoff. In this study the effect of nutrient enrichment on the progression of black band disease (BBD) was investigated using both in situ and laboratory experiments. Experimental increases in localized nutrient availability using commercial time release fertilizer in situ resulted in doubling of BBD progression and coral tissue loss in the common reef framework coral Siderastrea siderea. Laboratory experiments in which artificially infected S. siderea colonies were exposed to increased nitrate concentrations (up to 3 μM) demonstrated similar increases in BBD progression. These findings provide evidence that the impacts of this disease on coral populations are exacerbated by nutrient enrichment and that management to curtail excess nutrient loading may be important for reducing coral cover loss due to BBD.
Malin, Stephanie A; Mayer, Adam; Shreeve, Kelly; Olson-Hazboun, Shawn K; Adgate, John
2017-01-01
Unconventional oil and gas extraction (UOGE) has spurred an unprecedented boom in on-shore production in the U.S. Despite a surge in related research, a void exists regarding inquiries into policy outcomes and perceptions. To address this, support for federal regulatory exemptions for UOGE is examined using survey data collected in 2015 from two northern Colorado communities. Current regulatory exemptions for UOGE can be understood as components of broader societal processes of neoliberalization. Free market ideology increases public support for federal regulatory exemptions for UOGE. Perceived negative impacts do not necessarily drive people to support increased federal regulation. Utilizing neo-Polanyian theory, interaction between free market ideology and perceived negative impacts is explored. Free market ideology appears to moderate people's views of regulation: increasing the effect of perceived negative impacts while simultaneously increasing support for de regulation. To conclude, the ways in which free market ideology might normalize the impacts of UOGE activity are discussed.
Malin, Stephanie A.; Mayer, Adam; Shreeve, Kelly; Olson-Hazboun, Shawn K.; Adgate, John
2017-01-01
Unconventional oil and gas extraction (UOGE) has spurred an unprecedented boom in on-shore production in the U.S. Despite a surge in related research, a void exists regarding inquiries into policy outcomes and perceptions. To address this, support for federal regulatory exemptions for UOGE is examined using survey data collected in 2015 from two northern Colorado communities. Current regulatory exemptions for UOGE can be understood as components of broader societal processes of neoliberalization. Free market ideology increases public support for federal regulatory exemptions for UOGE. Perceived negative impacts do not necessarily drive people to support increased federal regulation. Utilizing neo-Polanyian theory, interaction between free market ideology and perceived negative impacts is explored. Free market ideology appears to moderate people’s views of regulation: increasing the effect of perceived negative impacts while simultaneously increasing support for deregulation. To conclude, the ways in which free market ideology might normalize the impacts of UOGE activity are discussed. PMID:29225425
Leonardo da Vinci and the Downburst.
NASA Astrophysics Data System (ADS)
Gedzelman, Stanley David
1990-05-01
Evidence from the drawings, experiments, and writings of Leonardo da Vinci are presented to demonstrate that da Vinci recognized and, possibly, discovered the downburst and understood its associated airflow. Other early references to vortex flows resembling downbursts are mentioned.
Violence and weapon-related trauma at Puruchuco-Huaquerones, Peru.
Murphy, Melissa S; Gaither, Catherine; Goycochea, Elena; Verano, John W; Cock, Guillermo
2010-08-01
Conquest of indigenous peoples in North America is understood primarily through ethnohistorical documents, archaeological evidence, and osteological analyses. However, in the Central Andes, the colonial enterprise and its effects are understood only from postcontact historical and ethnohistorical sources. Few archaeological and bioarchaeological studies have investigated Spanish Conquest and colonialism in the Andean region [for exceptions see Klaus and Tam: Am J Phys Anthropol 138 (2009) 356-368; Wernke, in press; and Quilter, in press]. Here we describe bioarchaeological evidence of violence from the cemeteries of Huaquerones and 57AS03 within the archaeological zone of Puruchuco-Huaquerones, Peru (circa A.D. 1470-1540). A total of 258 individuals greater than 15 years of age were analyzed for evidence of traumatic injuries. Individuals were examined macroscopically and evidence of traumatic injuries was analyzed according to the skeletal element involved, the location of the injury on the skeletal element, and any additional complications of the injury. This study examines and compares the evidence of perimortem injuries on skeletonized individuals from the two cemeteries and focuses specifically on the interpretation of weapon-related perimortem injuries. Evidence of perimortem trauma is present in both cemeteries (18.6%, 48/258); however, the frequency of injuries in 57AS03 is greater than that in Huaquerones (25.0% vs. 13.0%). Several injuries from 57AS03 are consistent with documented cases of injuries from firearms and 16th Century European weapons. We believe that the nature and high frequency of perimortem trauma at 57AS03 provide evidence of the violence that occurred with Spanish Conquest of the Inca Empire. Copyright 2010 Wiley-Liss, Inc.
Classification and definition of premature ejaculation.
Parnham, Arie; Serefoglu, Ege Can
2016-08-01
Premature ejaculation (PE) is a poorly understood condition and is considered as the most common sexual disorder in men. The ambiguity surrounding PE is in part due to the difficulty in conducting and interpreting research in the absence of a standardised definition that adequately encompasses the characteristics of these patients. An enhanced awareness of sexual dysfunctions in the recent decades has lead to an increase in scientific research that has challenged the traditional paradigm regarding PE. This has also enabled to establish a universal definition and classification of the disease. A move to a more evidence based approach has improved the clinicians' ability to define those who need medical treatment, as well as perform further research in this complex condition.
Breathlessness and blood: a combustible combination.
Popovsky, Mark A
2002-08-01
Pulmonary complications are increasingly recognized as serous hazards of transfusion. The evidence suggests that transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are underrecognized. Both present with dyspnea but other signs and symptoms assist in determining the proper diagnosis. Males and females are equally affected. Morbidity is significant with both complications and in the case of TRALI, the mortality is in the range of 6-10%. Although the clinical descriptions of both entities are well established, the clinical profile of the at-risk population for both TRALI and TACO is not well understood. Because early intervention can reduce morbidity, it is important that clinicians recognize these disorders and apply appropriate treatment.
[Brain oedema and acute liver failure].
Spahr, L
2003-04-01
Brain oedema leading to intracranial hypertension occurs in a significant proportion of patients with acute liver failure in whom it is a leading cause of death. Although precise pathogenic mechanisms associated to this severe complication remain incompletely understood, increasing evidence points to gut-derived neurotoxins including ammonia as key mediators in cerebral osmotic and perfusion disturbances. The management of brain oedema and intracranial hypertension requires a multidisciplinar approach in a center where liver transplantation is available, as this option is the only treatment modality that provides improvement in outcome. This article reviews the most common causes of acute liver failure and the standard of supportive care management, and describes future potential therapeutic aspects of brain oedema and intracranial hypertension.
Larsen, Junilla K; Vermulst, Ad A; Eisinga, Rob; English, Tammy; Gross, James J; Hofman, Elin; Scholte, Ron H J; Engels, Rutger C M E
2012-12-01
Expressive suppression is regarded as a generally ineffective emotion regulation strategy and appears to be associated with the development of depressive symptoms among adolescents. However, the mechanisms linking suppression to depressive symptoms are not well understood. The main aim of this study was to examine two potential mediators of the prospective relationship from depressive symptoms to expressive suppression among adolescents: parental support and peer victimization. Structural equation modelling was used to construct a three-wave cross-lagged model (n = 2,051 adolescents, 48.5 % female, at baseline; 1,465 with data at all three time points) with all possible longitudinal linkages. Depressive symptoms preceded decreases in perceived parental support 1 year later. Decreases in parental support mediated the relationship between depressive symptoms and increases in expressive suppression over a 2-year period. Multi-group analyses show that the mediation model tested was significant for girls, but not for boys. No evidence for other mediating models was found. Although initial suppression preceded increases in depressive symptoms 1 year later, we did not find any evidence for the reversed link from suppression to depressive symptoms. Clear evidence for a reciprocal relationship between depressive symptoms and parental support was found. However, only limited and inconsistent support was found for a reciprocal relationship between depressive symptoms and peer victimization. Finally, although some evidence for a unidirectional relationship from parental support to increases in suppression was found, no significant prospective relationship was found between peer victimization and suppression. The implications of our clear results for parental support, and mostly lacking results for peer victimization, are discussed.
Using animal models to determine the significance of complement activation in Alzheimer's disease
Loeffler, David A
2004-01-01
Complement inflammation is a major inflammatory mechanism whose function is to promote the removal of microorganisms and the processing of immune complexes. Numerous studies have provided evidence for an increase in this process in areas of pathology in the Alzheimer's disease (AD) brain. Because complement activation proteins have been demonstrated in vitro to exert both neuroprotective and neurotoxic effects, the significance of this process in the development and progression of AD is unclear. Studies in animal models of AD, in which brain complement activation can be experimentally altered, should be of value for clarifying this issue. However, surprisingly little is known about complement activation in the transgenic animal models that are popular for studying this disorder. An optimal animal model for studying the significance of complement activation on Alzheimer's – related neuropathology should have complete complement activation associated with senile plaques, neurofibrillary tangles (if present), and dystrophic neurites. Other desirable features include both classical and alternative pathway activation, increased neuronal synthesis of native complement proteins, and evidence for an increase in complement activation prior to the development of extensive pathology. In order to determine the suitability of different animal models for studying the role of complement activation in AD, the extent of complement activation and its association with neuropathology in these models must be understood. PMID:15479474
Sancilio, Amelia; Galbarczyk, Andrzej; Klimek, Magdalena
2016-01-01
Life history theory predicts trade-offs between reproductive effort and maternal survivorship in energy-restricted environments. However, empirical evidence for the positive association between maternal mortality and reproductive effort from energetically challenged human populations are mixed and physiological mechanisms that may underlie this association are poorly understood. We hypothesized that increases in aerobic metabolism during repeated periods of pregnancy and lactation result in increased oxidative stress that may contribute to somatic deterioration, vulnerability to illness, and accelerated aging. We therefore predicted that lifetime gravidity and parity would be related to levels of biomarkers of oxidative stress, as well as antioxidative defence enzymes in post-menopausal women. Our hypothesis was supported by positive linear associations between levels of 8-OHdG, a biomarker of DNA oxidative damage (β = 0.21, p<0.05), levels of antioxidative defence enzyme Cu-Zn SOD (β = 0.25, p<0.05), and number of lifetime pregnancies. Furthermore, independent of age and health status, post-menopausal women with higher gravidity and parity (> = 4 pregnancies per lifetime) had 20% higher levels of 8-OHdG and 60% higher levels of Cu-Zn SOD compared to women with lower gravidity and parity (<4 pregnancies per lifetime). Our results present the first evidence for oxidative stress as a possible cost of reproductive effort in humans. PMID:26761206
Ziomkiewicz, Anna; Sancilio, Amelia; Galbarczyk, Andrzej; Klimek, Magdalena; Jasienska, Grazyna; Bribiescas, Richard G
2016-01-01
Life history theory predicts trade-offs between reproductive effort and maternal survivorship in energy-restricted environments. However, empirical evidence for the positive association between maternal mortality and reproductive effort from energetically challenged human populations are mixed and physiological mechanisms that may underlie this association are poorly understood. We hypothesized that increases in aerobic metabolism during repeated periods of pregnancy and lactation result in increased oxidative stress that may contribute to somatic deterioration, vulnerability to illness, and accelerated aging. We therefore predicted that lifetime gravidity and parity would be related to levels of biomarkers of oxidative stress, as well as antioxidative defence enzymes in post-menopausal women. Our hypothesis was supported by positive linear associations between levels of 8-OHdG, a biomarker of DNA oxidative damage (β = 0.21, p<0.05), levels of antioxidative defence enzyme Cu-Zn SOD (β = 0.25, p<0.05), and number of lifetime pregnancies. Furthermore, independent of age and health status, post-menopausal women with higher gravidity and parity (> = 4 pregnancies per lifetime) had 20% higher levels of 8-OHdG and 60% higher levels of Cu-Zn SOD compared to women with lower gravidity and parity (<4 pregnancies per lifetime). Our results present the first evidence for oxidative stress as a possible cost of reproductive effort in humans.
Remote Sensing of Climate-Driven Range Shifts of Vegetation across North American Mountain Ranges
NASA Astrophysics Data System (ADS)
Kendrick, J. A.; Sax, D. F.; Kellner, J. R.
2015-12-01
Global climate change is driving shifts in local environmental conditions, and many organisms are projected to become poorly adapted to their current ranges. Some species may respond by gradually shifting their range limits to track environmental change. This adaptation strategy is expected to be most feasible in regions with sharp climatic gradients, such as mountain ranges. However, the extent to which this process is taking place is poorly understood, and some evidence suggests that shifts upwards in elevation might be more difficult than expected. Direct empirical evidence of range shifts in response to recent climate change could inform models and conservation strategies. Here we used Monte Carlo spectral unmixing of Landsat surface reflectance data to characterize changes in vegetation cover across major North American mountain ranges over the past 30 years. This approach allows us to observe changes in photosynthetic and nonphotosynthetic vegetation as well as absolute change in vegetation cover. We found evidence of a gradual increase in total vegetation cover at increasing elevations, but this pattern varied in its strength both within and among mountain ranges. We also observed more dramatic changes in vegetation type which differed strongly between regions with different climates. Our analysis shows that upslope range shift is a possible climate response in many cases, but that this process does not occur uniformly.
Mortazavi, Gh.; Mortazavi, S.A.R.; Mehdizadeh, A.R.
2018-01-01
A large body of evidence now indicates that the amount of mercury released from dental amalgam fillings can be significantly accelerated by exposure to radiofrequency electromagnetic fields (RF-EMFs) such as common mobile phones and magnetic resonance imaging (MRI). Studies performed on the increased microleakage of dental amalgam restorations after exposure to RF-EMFs have further supported these findings. Although the accelerated microleakage induced by RF-EMFs is clinically significant, the entire mechanisms of this phenomenon are not clearly understood. In this paper, we introduce “Triple M” effect, a new evidence-based theory which can explain the accelerated microleakage of dental amalgam fillings after exposure to different sources of electromagnetic radiation. Based on this theory, there are saliva-filled tiny spaces between amalgam and the tooth. Exposure of the oral cavity to RF-EMFs increases the energy of these small amounts of saliva. Due to the small mass of saliva in these tiny spaces, a small amount of energy will be required for heating. Moreover, reflection of the radiofrequency radiation on the inner walls of the tiny spaces causes interference which in turn produces some “hot spots” in these spaces. Finally, formation of gas bubbles in response to increased temperature and very rapid expansion of these bubbles will accelerate the microleakage of amalgam. Experiments that confirm the validity of this theory are discussed. PMID:29732349
Mortazavi, Gh; Mortazavi, S A R; Mehdizadeh, A R
2018-03-01
A large body of evidence now indicates that the amount of mercury released from dental amalgam fillings can be significantly accelerated by exposure to radiofrequency electromagnetic fields (RF-EMFs) such as common mobile phones and magnetic resonance imaging (MRI). Studies performed on the increased microleakage of dental amalgam restorations after exposure to RF-EMFs have further supported these findings. Although the accelerated microleakage induced by RF-EMFs is clinically significant, the entire mechanisms of this phenomenon are not clearly understood. In this paper, we introduce "Triple M" effect, a new evidence-based theory which can explain the accelerated microleakage of dental amalgam fillings after exposure to different sources of electromagnetic radiation. Based on this theory, there are saliva-filled tiny spaces between amalgam and the tooth. Exposure of the oral cavity to RF-EMFs increases the energy of these small amounts of saliva. Due to the small mass of saliva in these tiny spaces, a small amount of energy will be required for heating. Moreover, reflection of the radiofrequency radiation on the inner walls of the tiny spaces causes interference which in turn produces some "hot spots" in these spaces. Finally, formation of gas bubbles in response to increased temperature and very rapid expansion of these bubbles will accelerate the microleakage of amalgam. Experiments that confirm the validity of this theory are discussed.
Evidence on global medical travel.
Ruggeri, Kai; Záliš, Ladislav; Meurice, Christopher R; Hilton, Ian; Ly, Terry-Lisa; Zupan, Zorana; Hinrichs, Saba
2015-11-01
The potential benefits of travelling across national borders to obtain medical treatment include improved care, decreased costs and reduced waiting times. However, medical travel involves additional risks, compared to obtaining treatment domestically. We review the publicly-available evidence on medical travel. We suggest that medical travel needs to be understood in terms of its potential risks and benefits so that it can be evaluated against alternatives by patients who are seeking care. We propose three domains -quality standards, informed decision-making, economic and legal protection - in which better evidence could support the development of medical travel policies.
Age Differences in Self-Continuity: Converging Evidence and Directions for Future Research
Rutt, Joshua L.
2017-01-01
Abstract Life-span development is inherently linked to the perception of time and associated temporal construals. Such concepts are multi-faceted in nature and have important practical implications in areas such as time management, financial planning, or medical choices. A large body of research has documented age-related limitations in global time horizons, but age differences in other aspects of temporal construal are comparatively poorly understood. The present article draws attention to developmental trajectories of self-continuity, defined as perceived associations of one’s present self with past and future selves. After considering historical roots and contemporary views on self-continuity, we turn to the life-span developmental literature and review several convergent streams of research that provide indirect evidence for age-related increases in self-continuity. We then consider a small body of recent studies which have directly assessed age differences in self-continuity and summarize our current understanding of this phenomenon including associations between explicit and implicit measures, symmetry between past and future self-continuity, and differentiation from other aspects of time perception. We conclude by highlighting open theoretical questions and considering the practical implications of an increased sense of self-continuity with advancing age. PMID:28520940
Paternal care and litter size coevolution in mammals.
Stockley, Paula; Hobson, Liane
2016-04-27
Biparental care of offspring occurs in diverse mammalian genera and is particularly common among species with socially monogamous mating systems. Despite numerous well-documented examples, however, the evolutionary causes and consequences of paternal care in mammals are not well understood. Here, we investigate the evolution of paternal care in relation to offspring production. Using comparative analyses to test for evidence of evolutionary associations between male care and life-history traits, we explore if biparental care is likely to have evolved because of the importance of male care to offspring survival, or if evolutionary increases in offspring production are likely to result from the evolution of biparental care. Overall, we find no evidence that paternal care has evolved in response to benefits of supporting females to rear particularly costly large offspring or litters. Rather, our findings suggest that increases in offspring production are more likely to follow the evolution of paternal care, specifically where males contribute depreciable investment such as provisioning young. Through coevolution with litter size, we conclude that paternal care in mammals is likely to play an important role in stabilizing monogamous mating systems and could ultimately promote the evolution of complex social behaviours. © 2016 The Authors.
Paternal care and litter size coevolution in mammals
Hobson, Liane
2016-01-01
Biparental care of offspring occurs in diverse mammalian genera and is particularly common among species with socially monogamous mating systems. Despite numerous well-documented examples, however, the evolutionary causes and consequences of paternal care in mammals are not well understood. Here, we investigate the evolution of paternal care in relation to offspring production. Using comparative analyses to test for evidence of evolutionary associations between male care and life-history traits, we explore if biparental care is likely to have evolved because of the importance of male care to offspring survival, or if evolutionary increases in offspring production are likely to result from the evolution of biparental care. Overall, we find no evidence that paternal care has evolved in response to benefits of supporting females to rear particularly costly large offspring or litters. Rather, our findings suggest that increases in offspring production are more likely to follow the evolution of paternal care, specifically where males contribute depreciable investment such as provisioning young. Through coevolution with litter size, we conclude that paternal care in mammals is likely to play an important role in stabilizing monogamous mating systems and could ultimately promote the evolution of complex social behaviours. PMID:27097924
Corn, P.S.
2005-01-01
Amphibian life histories are exceedingly sensitive to temperature and precipitation, and there is good evidence that recent climate change has already resulted in a shift to breeding earlier in the year for some species. There are also suggestions that the recent increase in the occurrence of El Niño events has caused declines of anurans in Central America and is linked to elevated mortality of amphibian embryos in the northwestern United States. However, evidence linking amphibian declines in Central America to climate relies solely on correlations, and the mechanisms underlying the declines are not understood. Connections between embryo mortality and declines in abundance have not been demonstrated. Analyses of existing data have generally failed to find a link between climate and amphibian declines. It is likely, however, that future climate change will cause further declines of some amphibian species. Reduced soil moisture could reduce prey species and eliminate habitat. Reduced snowfall and increased summer evaporation could have dramatic effects on the duration or occurrence of seasonal wetlands, which are primary habitat for many species of amphibians. Climate change may be a relatively minor cause of current amphibian declines, but it may be the biggest future challenge to the persistence of many species
Hotchkiss, David R; Diana, Mark L; Foreit, Karen G Fleischman
2012-01-01
Health system performance depends on production and use of quality health data and information. Routine health information systems (RHIS) are defined as systems that provide information at regular intervals of a year or less to meet predictable information needs. These include paper-based or electronic health records and facility- and district-level management information systems. RHIS are receiving increasing attention as an essential component of efficient, country-owned, integrated national systems. To guide investment decisions on RHIS, evidence is needed on which types of RHIS interventions work and which do not. This chapter is a systematic review of the literature on the evaluation of RHIS interventions in low- and middle-income countries, starting from the premise that investments in RHIS could be better understood and so produce greater benefits than they currently do. We describe the conceptual literature on the determinants of RHIS performance and its role in improving health systems functioning, discuss the evidence base on the effectiveness of strategies to improve RHIS performance, provide an overview of RHIS evaluation challenges, and make suggestions to improve the evidence base. The goal is to help ensure that (a) RHIS interventions are appropriately designed and implemented to improve health systems functioning and (b) resulting RHIS information is used more effectively.
Systems theory and cascades in developmental psychopathology.
Cox, Martha J; Mills-Koonce, Roger; Propper, Cathi; Gariépy, Jean-Louis
2010-08-01
In the wake of prominent theoreticians in developmental science, whose contributions we review in this article, many developmental psychologists came to endorse a systems approach to understanding how the individual, as it develops, establishes functional relationships to social ecological contexts that from birth to school entry rapidly increase in complexity. The concept of developmental cascade has been introduced in this context to describe lawful processes by which antecedent conditions may be related with varying probabilities to specified outcomes. These are understood as processes by which function at one level or in one domain of behavior affect the organization of competency in later developing domains of general adaptation. Here we propose a developmental sequence by which the developing child acquires regulative capacities that are key to adjustment to a society that demands considerable control of emotional and cognitive functions early in life. We report empirical evidence showing that the acquisition of regulative capacities may be understood as a cascade of shifts in control parameters induced by the progressive integration of biological, transactional, and socioaffective systems over development. We conclude by suggesting how the developmental process may be accessed for effective intervention in populations deemed "at risk" for later problems of psychosocial adjustment.
Imprinted and X-linked non-coding RNAs as potential regulators of human placental function
Buckberry, Sam; Bianco-Miotto, Tina; Roberts, Claire T
2014-01-01
Pregnancy outcome is inextricably linked to placental development, which is strictly controlled temporally and spatially through mechanisms that are only partially understood. However, increasing evidence suggests non-coding RNAs (ncRNAs) direct and regulate a considerable number of biological processes and therefore may constitute a previously hidden layer of regulatory information in the placenta. Many ncRNAs, including both microRNAs and long non-coding transcripts, show almost exclusive or predominant expression in the placenta compared with other somatic tissues and display altered expression patterns in placentas from complicated pregnancies. In this review, we explore the results of recent genome-scale and single gene expression studies using human placental tissue, but include studies in the mouse where human data are lacking. Our review focuses on the ncRNAs epigenetically regulated through genomic imprinting or X-chromosome inactivation and includes recent evidence surrounding the H19 lincRNA, the imprinted C19MC cluster microRNAs, and X-linked miRNAs associated with pregnancy complications. PMID:24081302
Chakrabarti, Rumela; Wei, Yong; Hwang, Julie; Hang, Xiang; Blanco, Mario Andres; Choudhury, Abrar; Tiede, Benjamin; Romano, Rose-Anne; DeCoste, Christina; Mercatali, Laura; Ibrahim, Toni; Amadori, Dino; Kannan, Nagarajan; Eaves, Connie J; Sinha, Satrajit; Kang, Yibin
2014-01-01
Emerging evidence suggests that cancer is populated and maintained by tumor initiating cells (TICs) with stem-like properties similar to that of adult tissue stem cells. Despite recent advances, the molecular regulatory mechanisms that may be shared between normal and malignant stem cells remain poorly understood. Here we show that the ΔNp63 isoform of the Trp63 transcription factor promotes normal mammary stem cell (MaSC) activity by increasing the expression of the Wnt receptor Fzd7, thereby enhancing Wnt signaling. Importantly, Fzd7-dependent enhancement of Wnt signaling by ΔNp63 also governs tumor initiating activity of the basal subtype of breast cancer. These findings establish ΔNp63 as a key regulator of stem cells in both normal and malignant mammary tissues and provide direct evidence that breast cancer TICs and normal MaSCs share common regulatory mechanisms. PMID:25241036
Cross-disciplinary research in cancer: an opportunity to narrow the knowledge–practice gap
Urquhart, R.; Grunfeld, E.; Jackson, L.; Sargeant, J.; Porter, G.A.
2013-01-01
Health services researchers have consistently identified a gap between what is identified as “best practice” and what actually happens in clinical care. Despite nearly two decades of a growing evidence-based practice movement, narrowing the knowledge–practice gap continues to be a slow, complex, and poorly understood process. Here, we contend that cross-disciplinary research is increasingly relevant and important to reducing that gap, particularly research that encompasses the notion of transdisciplinarity, wherein multiple academic disciplines and non-academic individuals and groups are integrated into the research process. The assimilation of diverse perspectives, research approaches, and types of knowledge is potentially effective in helping research teams tackle real-world patient care issues, create more practice-based evidence, and translate the results to clinical and community care settings. The goals of this paper are to present and discuss cross-disciplinary approaches to health research and to provide two examples of how engaging in such research may optimize the use of research in cancer care. PMID:24311951
Cross-disciplinary research in cancer: an opportunity to narrow the knowledge-practice gap.
Urquhart, R; Grunfeld, E; Jackson, L; Sargeant, J; Porter, G A
2013-12-01
Health services researchers have consistently identified a gap between what is identified as "best practice" and what actually happens in clinical care. Despite nearly two decades of a growing evidence-based practice movement, narrowing the knowledge-practice gap continues to be a slow, complex, and poorly understood process. Here, we contend that cross-disciplinary research is increasingly relevant and important to reducing that gap, particularly research that encompasses the notion of transdisciplinarity, wherein multiple academic disciplines and non-academic individuals and groups are integrated into the research process. The assimilation of diverse perspectives, research approaches, and types of knowledge is potentially effective in helping research teams tackle real-world patient care issues, create more practice-based evidence, and translate the results to clinical and community care settings. The goals of this paper are to present and discuss cross-disciplinary approaches to health research and to provide two examples of how engaging in such research may optimize the use of research in cancer care.
Magnesium and cardiovascular complications of chronic kidney disease.
Massy, Ziad A; Drüeke, Tilman B
2015-07-01
Cardiovascular complications are the leading cause of death in patients with chronic kidney disease (CKD). Abundant experimental evidence suggests a physiological role of magnesium in cardiovascular function, and clinical evidence suggests a role of the cation in cardiovascular disease in the general population. The role of magnesium in CKD-mineral and bone disorder, and in particular its impact on cardiovascular morbidity and mortality in patients with CKD, is however not well understood. Experimental studies have shown that magnesium inhibits vascular calcification, both by direct effects on the vessel wall and by indirect, systemic effects. Moreover, an increasing number of epidemiologic studies in patients with CKD have shown associations of serum magnesium levels with intermediate and hard outcomes, including vascular calcification, cardiovascular events and mortality. Intervention trials in these patients conducted to date have had small sample sizes and have been limited to the study of surrogate parameters, such as arterial stiffness, vascular calcification and atherosclerosis. Randomized controlled trials are clearly needed to determine the effects of magnesium supplementation on hard outcomes in patients with CKD.
Hamling, Ian J; Hreinsdóttir, Sigrun; Bannister, Stephen; Palmer, Neville
2016-06-01
Continental rifting and seafloor spreading play a fundamental role in the generation of new crust. However, the distribution of magma and its relationship with tectonics and volcanism remain poorly understood, particularly in back-arc settings. We show evidence for a large, long-lived, off-axis magmatic intrusion located on the margin of the Taupo Volcanic Zone, New Zealand. Geodetic data acquired since the 1950s show evidence for uplift outside of the region of active extension, consistent with the inflation of a magmatic body at a depth of ~9.5 km. Satellite radar interferometry and Global Positioning System data suggest that there was an increase in the inflation rate from 2003 to 2011, which correlates with intense earthquake activity in the region. Our results suggest that the continued growth of a large magmatic body may represent the birth of a new magma chamber on the margins of a back-arc rift system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marks, Shawn M.; Lockhart, Samuel N.; Baker, Suzanne L.
Normal aging is associated with a decline in episodic memory and also with aggregation of the β-amyloid (Aβ) and tau proteins and atrophy of medial temporal lobe (MTL) structures crucial to memory formation. Although some evidence suggests that Aβ is associated with aberrant neural activity, the relationships among these two aggregated proteins, neural function, and brain structure are poorly understood. Using in vivo human Aβ and tau imaging, we demonstrate that increased Aβ and tau are both associated with aberrant fMRI activity in the MTL during memory encoding in cognitively normal older adults. This pathological neural activity was in turnmore » associated with worse memory performance and atrophy within the MTL. A mediation analysis revealed that the relationship with regional atrophy was explained by MTL tau. These findings broaden the concept of cognitive aging to include evidence of Alzheimer’s disease-related protein aggregation as an underlying mechanism of age-related memory impairment.« less
Reyes-Reyes, Elsa M; Aispuro, Ivan; Tavera-Garcia, Marco A; Field, Matthew; Moore, Sara; Ramos, Irma; Ramos, Kenneth S
2017-11-28
Although several lines of evidence have established the central role of epithelial-to-mesenchymal-transition (EMT) in malignant progression of non-small cell lung cancers (NSCLCs), the molecular events connecting EMT to malignancy remain poorly understood. This study presents evidence that Long Interspersed Nuclear Element-1 (LINE-1) retrotransposon couples EMT programming with malignancy in human bronchial epithelial cells (BEAS-2B). This conclusion is supported by studies showing that: 1) activation of EMT programming by TGF-β1 increases LINE-1 mRNAs and protein; 2) the lung carcinogen benzo(a)pyrene coregulates TGF-β1 and LINE-1 mRNAs, with LINE-1 positioned downstream of TGF-β1 signaling; and, 3) forced expression of LINE-1 in BEAS-2B cells recapitulates EMT programming and induces malignant phenotypes and tumorigenesis in vivo . These findings identify a TGFβ1-LINE-1 axis as a critical effector pathway that can be targeted for the development of precision therapies during malignant progression of intractable NSCLCs.
Can farm milk consumption prevent allergic diseases?
Braun-Fahrländer, C; von Mutius, E
2011-01-01
Cow's milk is an important part of human diet and a source of food allergy for some individuals. Medical guidance strongly discourages consumption of raw milk because of the known health risk associated with pathogenic bacteria present in unpasteurized milk. Despite these risks there is a growing body of epidemiological evidence suggesting that consumption of unprocessed cow's milk does not increase but rather decreases the risk of asthma, hay fever and atopic sensitisation. The article reviews the epidemiological literature and discusses components of unprocessed milk potentially responsible for this protection. It focuses on the role of bacteria in raw milk, the fatty acid profile, whey proteins and finally the role of allergens in milk. Although the epidemiological evidence consistently suggest a protective role of unprocessed cow's milk consumption on the development of asthma, hay fever and atopic sensitization the underlying mechanisms are not yet understood and the consumption of raw milk cannot be recommended as a preventive measure for allergic diseases. © 2010 Blackwell Publishing Ltd.
Vally, Zahir; Murray, Lynne; Tomlinson, Mark; Cooper, Peter J
2015-08-01
Dialogic book-sharing is an interactive form of shared reading. It has been shown in high income countries (HICs) to be of significant benefit to child cognitive development. Evidence for such benefit in low and middle income countries (LMICs) is scarce, although a feasibility study of our own produced encouraging findings. Accordingly, we aimed to establish the impact on child language and attention of providing training in dialogic booksharing to carers of infants in an impoverished South African community. We conducted a randomized controlled trial in Khayelitsha, an informal settlement in South Africa. Mothers of infants aged between 14 and 16 months were recruited and randomized to either 8 weeks of manualized training in dialogic book-sharing or a no-intervention control group. Independent assessments were made of infant language and attention at baseline and following training. The trial was registered (ISRCTN39953901). Ninety one carer-infant dyads were recruited and randomized to the intervention group (n = 49) or the control group (n = 42), 82 (90%) of whom were available for follow-up assessments. On a standardized carer report of infant vocabulary, compared to those in the control group, carers who received the intervention reported a significantly greater increase in the number of words understood by their infants as well as a larger increase in the number of words that their infant understood and could vocalize. Intervention group children also showed substantially greater gains on a measure of sustained attention. In line with evidence from HICs, a dialogic book-sharing programme delivered to an impoverished South African sample was shown to be of considerable benefit to the development of child language and focussed attention. The training programme, which is simple and inexpensive to deliver, has the potential to benefit child cognitive development in LMIC contexts where such development is commonly compromised. © 2014 Association for Child and Adolescent Mental Health.
Vally, Zahir; Murray, Lynne; Tomlinson, Mark; Cooper, Peter J.
2015-01-01
Background Dialogic book-sharing is an interactive form of shared reading. It has been shown in high income countries (HICs) to be of significant benefit to child cognitive development. Evidence for such benefit in low and middle income countries (LMICs) is scarce, although a feasibility study of our own produced encouraging findings. Accordingly, we aimed to establish the impact on child language and attention of providing training in dialogic booksharing to carers of infants in an impoverished South African community. Methods We conducted a randomized controlled trial in Khayelitsha, an informal settlement in South Africa. Mothers of infants aged between 14 and 16 months were recruited and randomized to either eight weeks of manualized training in dialogic book-sharing or a no-intervention control group. Independent assessments were made of infant language and attention at baseline and following training. The trial was registered (ISRCTN39953901). Results Ninety one carer-infant dyads were recruited and randomized to the intervention group (n = 49) or the control group (n = 42), 82 (90%) of whom were available for follow-up assessments. On a standardized carer report of infant vocabulary, compared to those in the control group, carers who received the intervention reported a significantly greater increase in the number of words understood by their infants as well as a larger increase in the number of words that their infant understood and could vocalize. Intervention group children also showed substantially greater gains on a measure of sustained attention. Conclusions In line with evidence from HICs, a dialogic book-sharing programme delivered to an impoverished South African sample was shown to be of considerable benefit to the development of child language and focussed attention. The training programme, which is simple and inexpensive to deliver, has the potential to benefit child cognitive development in LMIC contexts where such development is commonly compromised. PMID:25399699
Salary, Performance, and Superintendent Turnover
ERIC Educational Resources Information Center
Grissom, Jason A.; Mitani, Hajime
2016-01-01
Purpose: Superintendent retention is an important goal for many school districts, yet the factors contributing to superintendent turnover are poorly understood. Most prior quantitative studies of superintendent turnover have relied on small, cross-sectional samples, limiting the evidence base. Utilizing longitudinal administrative records from…
Gries, Katharine Suzanne; Esser, Dirk; Wiklund, Ingela
2013-09-16
The study objective was to assess the content validity of the Cough and Sputum Assessment Questionnaire (CASA-Q) cough domains and the UCSD Shortness of Breath Questionnaire (SOBQ) for use in patients with Idiopathic Pulmonary Fibrosis (IPF). Cross-sectional, qualitative study with cognitive interviews in patients with IPF. Study outcomes included relevance, comprehension of item meaning, understanding of the instructions, recall period, response options, and concept saturation. Interviews were conducted with 18 IPF patients. The mean age was 68.9 years (SD 11.9), 77.8% were male, and 88.9% were Caucasian. The intended meaning of the CASA-Q cough domain items was clearly understood by most of the participants (89-100%). All participants understood the CASA-Q instructions; the correct recall period was reported by 89% of the patients, and the response options were understood by 76%. The intended meaning of the UCSD-SOBQ items was relevant and clearly understood by all participants. Participants understood the instructions (83%) and all patients understood the response options (100%). The reported recall period varied based on the type of activity performed. No concepts were missing, suggesting that saturation was demonstrated for both measures. This study provides evidence for content validity for the CASA-Q cough domains and the UCSD-SOBQ for patients with IPF. Items of both questionnaires were understood and perceived as relevant to measure the key symptoms of IPF. The results of this study support the use of these instruments in IPF clinical trials as well as further studies of their psychometric properties.
Garritty, Chantelle; Stevens, Adrienne; Gartlehner, Gerald; King, Valerie; Kamel, Chris
2016-10-28
Policymakers and healthcare stakeholders are increasingly seeking evidence to inform the policymaking process, and often use existing or commissioned systematic reviews to inform decisions. However, the methodologies that make systematic reviews authoritative take time, typically 1 to 2 years to complete. Outside the traditional SR timeline, "rapid reviews" have emerged as an efficient tool to get evidence to decision-makers more quickly. However, the use of rapid reviews does present challenges. To date, there has been limited published empirical information about this approach to compiling evidence. Thus, it remains a poorly understood and ill-defined set of diverse methodologies with various labels. In recent years, the need to further explore rapid review methods, characteristics, and their use has been recognized by a growing network of healthcare researchers, policymakers, and organizations, several with ties to Cochrane, which is recognized as representing an international gold standard for high-quality, systematic reviews. In this commentary, we introduce the newly established Cochrane Rapid Reviews Methods Group developed to play a leading role in guiding the production of rapid reviews given they are increasingly employed as a research synthesis tool to support timely evidence-informed decision-making. We discuss how the group was formed and outline the group's structure and remit. We also discuss the need to establish a more robust evidence base for rapid reviews in the published literature, and the importance of promoting registration of rapid review protocols in an effort to promote efficiency and transparency in research. As with standard systematic reviews, the core principles of evidence-based synthesis should apply to rapid reviews in order to minimize bias to the extent possible. The Cochrane Rapid Reviews Methods Group will serve to establish a network of rapid review stakeholders and provide a forum for discussion and training. By facilitating exchange, the group will strive to conduct research to advance the methods of rapid reviews.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zak, Donald R.
A growing body of evidence reveals that anthropogenic N deposition can reduce the microbial decay of plant detritus and increase soil C storage across a wide range of terrestrial ecosystems. This aspect of global change has the potential to constrain the accumulation of anthropogenic CO 2 in the Earth’s atmosphere, and hence slow the pace of climate warming. The molecular and microbial mechanisms underlying this biogeochemical response are not understood, and they are not a component of any coupled climate-biogeochemical model estimating ecosystem C storage, and hence, the future climate of an N-enriched Earth. Here, we report the use ofmore » genomic-enabled approaches to identify the molecular underpinnings of the microbial mechanisms leading to greater soil C storage in response to anthropogenic N deposition, thereby enabling us to better anticipate changes in soil C storage.« less
Obesity as an important risk factor for certain types of cancer.
Davoodi, Sayed Hossain; Malek-Shahabi, Talieh; Malekshahi-Moghadam, Ali; Shahbazi, Roghieh; Esmaeili, Saeideh
2013-01-01
Cancer could be described as the uncontrolled and unrestricted growth of malignant cells in any place of the body. It is a multifactorial disease which either heredity or environmental factors (such as nutrition, physical inactivity, alcohol, obesity, exposure to sun, environmental pollutants, infections) chip in incidence of cancer. In recent years, several researchers have focused on obesity as a potent cancer risk factor. Scientificevidences have suggested that obesity has associated with increased risk for a plenty of different types of cancer. The evidences are the most consistent for endometrial cancer, breast cancer between the postmenopausal women, and renal cell cancer. More contradictoryresults have reported about the colorectal, prostate, and pancreatic cancer. Although numerous studies have done according to the obesity and cancer relation or joint, but the molecular mechanisms in which obesity could increase the risks of cancer, have been poorly understood.
Poroelastic Mechanical Effects of Hemicelluloses on Cellulosic Hydrogels under Compression
Lopez-Sanchez, Patricia; Cersosimo, Julie; Wang, Dongjie; Flanagan, Bernadine; Stokes, Jason R.; Gidley, Michael J.
2015-01-01
Hemicelluloses exhibit a range of interactions with cellulose, the mechanical consequences of which in plant cell walls are incompletely understood. We report the mechanical properties of cell wall analogues based on cellulose hydrogels to elucidate the contribution of xyloglucan or arabinoxylan as examples of two hemicelluloses displaying different interactions with cellulose. We subjected the hydrogels to mechanical pressures to emulate the compressive stresses experienced by cell walls in planta. Our results revealed that the presence of either hemicellulose increased the resistance to compression at fast strain rates. However, at slow strain rates, only xyloglucan increased composite strength. This behaviour could be explained considering the microstructure and the flow of water through the composites confirming their poroelastic nature. In contrast, small deformation oscillatory rheology showed that only xyloglucan decreased the elastic moduli. These results provide evidence for contrasting roles of different hemicelluloses in plant cell wall mechanics and man-made cellulose-based composite materials. PMID:25794048
Identifying external influences on global precipitation
Marvel, Kate; Bonfils, Céline
2013-01-01
Changes in global (ocean and land) precipitation are among the most important and least well-understood consequences of climate change. Increasing greenhouse gas concentrations are thought to affect the zonal-mean distribution of precipitation through two basic mechanisms. First, increasing temperatures will lead to an intensification of the hydrological cycle (“thermodynamic” changes). Second, changes in atmospheric circulation patterns will lead to poleward displacement of the storm tracks and subtropical dry zones and to a widening of the tropical belt (“dynamic” changes). We demonstrate that both these changes are occurring simultaneously in global precipitation, that this behavior cannot be explained by internal variability alone, and that external influences are responsible for the observed precipitation changes. Whereas existing model experiments are not of sufficient length to differentiate between natural and anthropogenic forcing terms at the 95% confidence level, we present evidence that the observed trends result from human activities. PMID:24218561
Identifying external influences on global precipitation.
Marvel, Kate; Bonfils, Céline
2013-11-26
Changes in global (ocean and land) precipitation are among the most important and least well-understood consequences of climate change. Increasing greenhouse gas concentrations are thought to affect the zonal-mean distribution of precipitation through two basic mechanisms. First, increasing temperatures will lead to an intensification of the hydrological cycle ("thermodynamic" changes). Second, changes in atmospheric circulation patterns will lead to poleward displacement of the storm tracks and subtropical dry zones and to a widening of the tropical belt ("dynamic" changes). We demonstrate that both these changes are occurring simultaneously in global precipitation, that this behavior cannot be explained by internal variability alone, and that external influences are responsible for the observed precipitation changes. Whereas existing model experiments are not of sufficient length to differentiate between natural and anthropogenic forcing terms at the 95% confidence level, we present evidence that the observed trends result from human activities.
Poroelastic mechanical effects of hemicelluloses on cellulosic hydrogels under compression.
Lopez-Sanchez, Patricia; Cersosimo, Julie; Wang, Dongjie; Flanagan, Bernadine; Stokes, Jason R; Gidley, Michael J
2015-01-01
Hemicelluloses exhibit a range of interactions with cellulose, the mechanical consequences of which in plant cell walls are incompletely understood. We report the mechanical properties of cell wall analogues based on cellulose hydrogels to elucidate the contribution of xyloglucan or arabinoxylan as examples of two hemicelluloses displaying different interactions with cellulose. We subjected the hydrogels to mechanical pressures to emulate the compressive stresses experienced by cell walls in planta. Our results revealed that the presence of either hemicellulose increased the resistance to compression at fast strain rates. However, at slow strain rates, only xyloglucan increased composite strength. This behaviour could be explained considering the microstructure and the flow of water through the composites confirming their poroelastic nature. In contrast, small deformation oscillatory rheology showed that only xyloglucan decreased the elastic moduli. These results provide evidence for contrasting roles of different hemicelluloses in plant cell wall mechanics and man-made cellulose-based composite materials.
Melt onset over Arctic sea ice controlled by atmospheric moisture transport
NASA Astrophysics Data System (ADS)
Mortin, Jonas; Svensson, Gunilla; Graversen, Rune G.; Kapsch, Marie-Luise; Stroeve, Julienne C.; Boisvert, Linette N.
2016-06-01
The timing of melt onset affects the surface energy uptake throughout the melt season. Yet the processes triggering melt and causing its large interannual variability are not well understood. Here we show that melt onset over Arctic sea ice is initiated by positive anomalies of water vapor, clouds, and air temperatures that increase the downwelling longwave radiation (LWD) to the surface. The earlier melt onset occurs; the stronger are these anomalies. Downwelling shortwave radiation (SWD) is smaller than usual at melt onset, indicating that melt is not triggered by SWD. When melt occurs early, an anomalously opaque atmosphere with positive LWD anomalies preconditions the surface for weeks preceding melt. In contrast, when melt begins late, clearer than usual conditions are evident prior to melt. Hence, atmospheric processes are imperative for melt onset. It is also found that spring LWD increased during recent decades, consistent with trends toward an earlier melt onset.
MicroRNAs and cancer resistance: A new molecular plot.
Fanini, F; Fabbri, M
2016-05-01
The most common cause of cancer relapse is drug resistance, acquired or intrinsic, which strongly limits the efficacy of both conventional and new targeted chemotherapy. MicroRNAs (miRNAs) are a growing, large family of short noncoding RNAs frequently dysregulated in malignancies. Although the mechanism of miRNA-mediated drug resistance is not fully understood, an increasing amount of evidence suggests their involvement in the acquisition of tumor cell drug resistance, pointing towards the need for novel and more innovative therapeutic approaches. Use of antagomiRs or mimics can modulate specific miRNAs in order to restore gene networks and signaling pathways, perhaps optimizing chemotherapies by increasing cancer cell sensitivity to drugs. The aim of this review is to provide a state-of-the-art scenario with regard to the most recent discoveries in the field of miRNAs involved in the process of resistance to cancer therapy. © 2016 The American Society for Clinical Pharmacology and Therapeutics.
Fetal-to-maternal signaling to initiate parturition
Reinl, Erin L.; England, Sarah K.
2015-01-01
Multiple processes are capable of activating the onset of parturition; however, the specific contributions of the mother and the fetus to this process are not fully understood. In this issue of the JCI, Gao and colleagues present evidence that steroid receptor coactivators 1 and 2 (SRC-1 and SRC-2) regulate surfactant protein-A (SP-A) and platelet-activating factor (PAF) expression, which increases in the developing fetal lung. WT dams crossed with males deficient for both SRC-1 and SRC-2 had suppressed myometrial inflammation, increased serum progesterone, and delayed parturition, which could be reconciled by injection of either SP-A or PAF into the amnion. Together, the results of this study demonstrate that the fetal lungs produce signals to initiate labor in the mouse. This work underscores the importance of the fetus as a contributor to the onset of murine, and potentially human, parturition. PMID:26098207
Polarization vision seldom increases the sighting distance of silvery fish.
Johnsen, Sönke; Gagnon, Yakir L; Marshall, N Justin; Cronin, Thomas W; Gruev, Viktor; Powell, Samuel
2016-08-22
Although the function of polarization vision, the ability to discern the polarization characteristics of light, is well established in many terrestrial and benthic species, its purpose in pelagic species (squid and certain fish and crustaceans) is poorly understood [1]. A long-held hypothesis is that polarization vision in open water is used to break the mirror camouflage of silvery fish, as biological mirrors can change the polarization of reflected light [2,3]. Although, the addition of polarization information may increase the conspicuousness of silvery fish at close range, direct evidence that silvery fish - or indeed any pelagic animal - are visible at longer distances using polarization vision rather than using radiance (i.e. brightness) vision is lacking. Here we show, using in situ polarization imagery and a new visual detection model, that polarization vision does not in fact appear to allow viewers to see silvery fish at greater distances. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fletcher, Quinn E.; Selman, Colin; Boutin, Stan; McAdam, Andrew G.; Woods, Sarah B.; Seo, Arnold Y.; Leeuwenburgh, Christiaan; Speakman, John R.; Humphries, Murray M.
2013-01-01
A central principle in life-history theory is that reproductive effort negatively affects survival. Costs of reproduction are thought to be physiologically-based, but the underlying mechanisms remain poorly understood. Using female North American red squirrels (Tamiasciurus hudsonicus), we test the hypothesis that energetic investment in reproduction overwhelms investment in antioxidant protection, leading to oxidative damage. In support of this hypothesis we found that the highest levels of plasma protein oxidative damage in squirrels occurred during the energetically-demanding period of lactation. Moreover, plasma protein oxidative damage was also elevated in squirrels that expended the most energy and had the lowest antioxidant protection. Finally, we found that squirrels that were food-supplemented during lactation and winter had increased antioxidant protection and reduced plasma protein oxidative damage providing the first experimental evidence in the wild that access to abundant resources can reduce this physiological cost. PMID:23617928
Dietary antiaging phytochemicals and mechanisms associated with prolonged survival
Si, Hongwei; Liu, Dongmin
2014-01-01
Aging is well-known an inevitable process that is influenced by genetic, lifestyle and environmental factors. However, the exact mechanisms underlying the aging process are not well understood. Increasing evidence shows that aging is highly associated with chronic increase in reactive oxygen species (ROS), accumulation of a low-grade proinflammatory phenotype and reduction in age-related autophagy, suggesting that these factors may play important roles in promoting aging. Indeed, reduction of ROS and low-grade inflammation and promotion of autophagy by calorie restriction or other dietary manipulation can extend lifespan in a wide spectrum of model organisms. Interestingly, recent studies show that some food-derived small molecules, also called phytochemicals, can extend lifespan in various animal species. In this paper, we review several recently identified potential antiaging phytochemicals that have been studied in cells, animals and humans and further highlight the cellular and molecular mechanisms underlying the antiaging actions by these molecules. PMID:24742470
BAD Modulates Counterregulatory Responses to Hypoglycemia and Protective Glucoprivic Feeding
Osundiji, Mayowa A.; Godes, Marina L.; Evans, Mark L.; Danial, Nika N.
2011-01-01
Hypoglycemia or glucoprivation triggers protective hormonal counterregulatory and feeding responses to aid the restoration of normoglycemia. Increasing evidence suggests pertinent roles for the brain in sensing glucoprivation and mediating counterregulation, however, the precise nature of the metabolic signals and molecular mediators linking central glucose sensing to effector functions are not fully understood. Here, we demonstrate that protective hormonal and feeding responses to hypoglycemia are regulated by BAD, a BCL-2 family protein with dual functions in apoptosis and metabolism. BAD-deficient mice display impaired glycemic and hormonal counterregulatory responses to systemic glucoprivation induced by 2-deoxy-D-glucose. BAD is also required for proper counterregulatory responses to insulin-induced hypoglycemia as evident from significantly higher glucose infusion rates and lower plasma epinephrine levels during hyperinsulinemic hypoglycemic clamps. Importantly, RNA interference-mediated acute knockdown of Bad in the brain provided independent genetic evidence for its relevance in central glucose sensing and proper neurohumoral responses to glucoprivation. Moreover, BAD deficiency is associated with impaired glucoprivic feeding, suggesting that its role in adaptive responses to hypoglycemia extends beyond hormonal responses to regulation of feeding behavior. Together, these data indicate a previously unappreciated role for BAD in the control of central glucose sensing. PMID:22162752
Teaching Creativity and Inventive Problem Solving in Science
2009-01-01
Engaging learners in the excitement of science, helping them discover the value of evidence-based reasoning and higher-order cognitive skills, and teaching them to become creative problem solvers have long been goals of science education reformers. But the means to achieve these goals, especially methods to promote creative thinking in scientific problem solving, have not become widely known or used. In this essay, I review the evidence that creativity is not a single hard-to-measure property. The creative process can be explained by reference to increasingly well-understood cognitive skills such as cognitive flexibility and inhibitory control that are widely distributed in the population. I explore the relationship between creativity and the higher-order cognitive skills, review assessment methods, and describe several instructional strategies for enhancing creative problem solving in the college classroom. Evidence suggests that instruction to support the development of creativity requires inquiry-based teaching that includes explicit strategies to promote cognitive flexibility. Students need to be repeatedly reminded and shown how to be creative, to integrate material across subject areas, to question their own assumptions, and to imagine other viewpoints and possibilities. Further research is required to determine whether college students' learning will be enhanced by these measures. PMID:19723812
Teaching creativity and inventive problem solving in science.
DeHaan, Robert L
2009-01-01
Engaging learners in the excitement of science, helping them discover the value of evidence-based reasoning and higher-order cognitive skills, and teaching them to become creative problem solvers have long been goals of science education reformers. But the means to achieve these goals, especially methods to promote creative thinking in scientific problem solving, have not become widely known or used. In this essay, I review the evidence that creativity is not a single hard-to-measure property. The creative process can be explained by reference to increasingly well-understood cognitive skills such as cognitive flexibility and inhibitory control that are widely distributed in the population. I explore the relationship between creativity and the higher-order cognitive skills, review assessment methods, and describe several instructional strategies for enhancing creative problem solving in the college classroom. Evidence suggests that instruction to support the development of creativity requires inquiry-based teaching that includes explicit strategies to promote cognitive flexibility. Students need to be repeatedly reminded and shown how to be creative, to integrate material across subject areas, to question their own assumptions, and to imagine other viewpoints and possibilities. Further research is required to determine whether college students' learning will be enhanced by these measures.
[THE GIFT OF THE APPLICATION OF REIKI THERAPY IN CANCER PATIENTS].
Sánchez Domínguez, Javier
2016-06-01
Pain is one of the most feared symptoms of cancer. Bad pain not properly relieved contributes to the suffering of the patient and family. This may encourage them to seek additional complementary and alternative therapies, such as the one in our literature review. Reiki is understood as a healing method that uses universal energy to achieve balance and harmony of body, mind and soul, through the laying on of hands. Reiki is a relatively new the rapyin relation to the relief of the symptoms of cancer. In fact, there are still a few articles in this field. Currently, the authors explore the evidence on the effectiveness of Reiki in relation to cancer pain and symptom control. Due to the increased interest deposited in Reiki by the health professionals--especially for oncology professionals--to relieve the symptoms of cancer, there has been a synthesis of recent studies to provide the evidence so far. After our literature review, we can conclude that there is insufficient evidence on the effectiveness of Reiki in relieving the cancer's symptoms due to the small sample size used, the paucity of studies and the abandonment of the study participants and others.
INTERNATIONAL CHILDHOOD CANCER COHORT CONSORTIUM (Journal Article)
Childhood cancers are rare conditions whose etiology is poorly understood. There is evidence that for some, the causal pathway may commence in utero or during peri-conception. One traditional epidemiologic approach to the study of rare diseases is the use of a retrospective cas...
Effects of Macrophage Depletion on Sleep in Mice
Ames, Conner; Boland, Erin; Szentirmai, Éva
2016-01-01
The reciprocal interaction between the immune system and sleep regulation has been widely acknowledged but the cellular mechanisms that underpin this interaction are not completely understood. In the present study, we investigated the role of macrophages in sleep loss- and cold exposure-induced sleep and body temperature responses. Macrophage apoptosis was induced in mice by systemic injection of clodronate-containing liposomes (CCL). We report that CCL treatment induced an immediate and transient increase in non-rapid-eye movement sleep (NREMS) and fever accompanied by decrease in rapid-eye movement sleep, motor activity and NREMS delta power. Chronically macrophage-depleted mice had attenuated NREMS rebound after sleep deprivation compared to normal mice. Cold-induced increase in wakefulness and decrease in NREMS, rapid-eye movement sleep and body temperature were significantly enhanced in macrophage-depleted mice indicating increased cold sensitivity. These findings provide further evidence for the reciprocal interaction among the immune system, sleep and metabolism, and identify macrophages as one of the key cellular elements in this interplay. PMID:27442442
Prostatic cancers: understanding their molecular pathology and the 2016 WHO classification
Inamura, Kentaro
2018-01-01
Accumulating evidence suggests that prostatic cancers represent a group of histologically and molecularly heterogeneous diseases with variable clinical courses. In accordance with the increased knowledge of their clinicopathologies and genetics, the World Health Organization (WHO) classification of prostatic cancers has been revised. Additionally, recent data on their comprehensive molecular characterization have increased our understanding of the genomic basis of prostatic cancers and enabled us to classify them into subtypes with distinct molecular pathologies and clinical features. Our increased understanding of the molecular pathologies of prostatic cancers has permitted their evolution from a poorly understood, heterogeneous group of diseases with variable clinical courses to characteristic molecular subtypes that allow the implementation of personalized therapies and better patient management. This review provides perspectives on the new 2016 WHO classification of prostatic cancers as well as recent knowledge of their molecular pathologies. The WHO classification of prostatic cancers will require additional revisions to allow for reliable and clinically meaningful cancer diagnoses as a better understanding of their molecular characteristics is obtained. PMID:29581876
Interactions between soil and tree roots accelerate long-term soil carbon decomposition.
Dijkstra, Feike A; Cheng, Weixin
2007-11-01
Decomposition of soil organic carbon (SOC) is the main process governing the release of CO(2) into the atmosphere from terrestrial systems. Although the importance of soil-root interactions for SOC decomposition has increasingly been recognized, their long-term effect on SOC decomposition remains poorly understood. Here we provide experimental evidence for a rhizosphere priming effect, in which interactions between soil and tree roots substantially accelerate SOC decomposition. In a 395-day greenhouse study with Ponderosa pine and Fremont cottonwood trees grown in three different soils, SOC decomposition in the planted treatments was significantly greater (up to 225%) than in soil incubations alone. This rhizosphere priming effect persisted throughout the experiment, until well after initial soil disturbance, and increased with a greater amount of root-derived SOC formed during the experiment. Loss of old SOC was greater than the formation of new C, suggesting that increased C inputs from roots could result in net soil C loss.
Reassessing Immune Control of Hepatitis A Virus
Walker, Christopher M.; Feng, Zongdi; Lemon, Stanley M.
2015-01-01
There is renewed interest in hepatitis A virus (HAV) pathogenesis and immunity after 2–3 decades of limited progress. From a public health perspective, the average age at infection has increased in developing countries, resulting in more severe hepatitis that is poorly understood mechanistically. More fundamentally, there is interest in comparing immunity to HAV and hepatitis C virus (HCV): small, positive-strand RNA viruses with very different infection outcomes. Here, we review evidence that circulating HAV virions are cloaked in membranes, with consequences for induction of innate immunity and antibody-mediated neutralization. We also consider the contribution of CD4+ helper versus CD8+ cytotoxic T cells to antiviral immunity and liver injury, and present a model of non-cytotoxic immune control of HAV infection. PMID:25617494
Perspectives and challenges of antioxidant therapy for atrial fibrillation.
Gasparova, Iveta; Kubatka, Peter; Opatrilova, Radka; Caprnda, Martin; Filipova, Slavomira; Rodrigo, Luis; Malan, Leone; Mozos, Ioana; Rabajdova, Miroslava; Nosal, Vladimir; Kobyliak, Nazarii; Valentova, Vanda; Petrovic, Daniel; Adamek, Mariusz; Kruzliak, Peter
2017-01-01
Atrial fibrillation (AF) is the most common sustained arrhythmia associated with significant morbidity and mortality. The mechanisms underlying the pathogenesis of AF are poorly understood, although electrophysiological remodeling has been described as an important initiating step. There is growing evidence that oxidative stress is involved in the pathogenesis of AF. Many known triggers of oxidative stress, such as age, diabetes, smoking, and inflammation, are linked with an increased risk of arrhythmia. Numerous preclinical studies and clinical trials reported the importance of antioxidant therapy in the prevention of AF, using vitamins C and E, polyunsaturated fatty acids, statins, or nitric oxide donors. The aim of our work is to give a current overview and analysis of opportunities, challenges, and benefits of antioxidant therapy in AF.
Understanding Female Students' Physics Identity Development
NASA Astrophysics Data System (ADS)
Hazari, Zahra
2017-01-01
While the gender gap in physics participation is a known problem, practical strategies that may improve the situation are not well understood. As physics education researchers, we draw on evidence to help inform us of what may or may not be working. To this end, physics identity has proven to be a useful framework for understanding and predicting participation in physics. Drawing on data from national surveys of college students, case studies in physics classes, and surveys of undergraduate women in physics, we identify strategies that are predictive of female students' physics identity development from their high school and undergraduate physics experiences. These findings will be discussed as well as future directions for using this research to increase the recruitment of women to physics-related careers. NSF Grant # 1431846.
Deadly targeting of women in promoting cigarettes.
O'Keefe, A M; Pollay, R W
1996-01-01
The history of tobacco marketing portrays a strong relationship between cigarette advertising targeted to women and the rise in the prevalence of women smoking. This article describes how tobacco companies crafted their marketing strategies to obfuscate the growing evidence of the health hazards of tobacco and to circumvent attempts to regulate cigarette advertising. It shows how the tobacco industry understood and capitalized on the women's liberation movement to sell cigarettes as symbols of freedom and emancipation, tracing the creation and promotion of Virginia Slims as a case study. And it documents the unfortunate success of these marketing strategies as reflected in the trends of tobacco use, especially among underage girls, and the commensurate increase in tobacco-related disease and death among women.
Clinical immunology review series: an approach to desensitization
Krishna, M T; Huissoon, A P
2011-01-01
Allergen immunotherapy describes the treatment of allergic disease through administration of gradually increasing doses of allergen. This form of immune tolerance induction is now safer, more reliably efficacious and better understood than when it was first formally described in 1911. In this paper the authors aim to summarize the current state of the art in immunotherapy in the treatment of inhalant, venom and drug allergies, with specific reference to its practice in the United Kingdom. A practical approach has been taken, with reference to current evidence and guidelines, including illustrative protocols and vaccine schedules. A number of novel approaches and techniques are likely to change considerably the way in which we select and treat allergy patients in the coming decade, and these advances are previewed. PMID:21175592
The Impact of Social Support on Outcomes in Adult Patients with Type 2 Diabetes: A Systematic Review
Strom, Joni L.; Egede, Leonard E.
2012-01-01
Diabetes is one of the fastest growing chronic diseases globally and in the United States. Although preventable, type 2 diabetes accounts for 90% of all cases of diabetes worldwide and continues to be a source of increased disability, lost productivity, mortality, and amplified health-care costs. Proper disease management is crucial for achieving better diabetes-related outcomes. Evidence suggests that higher levels of social support are associated with improved clinical outcomes, reduced psychosocial symptomatology, and the adaptation of beneficial lifestyle activities; however, the role of social support in diabetes management is not well understood. The purpose of this systematic review is to examine the impact of social support on outcomes in adults with type 2 diabetes. PMID:22949135
Evidence on global medical travel
Záliš, Ladislav; Meurice, Christopher R; Hilton, Ian; Ly, Terry-Lisa; Zupan, Zorana; Hinrichs, Saba
2015-01-01
Abstract The potential benefits of travelling across national borders to obtain medical treatment include improved care, decreased costs and reduced waiting times. However, medical travel involves additional risks, compared to obtaining treatment domestically. We review the publicly-available evidence on medical travel. We suggest that medical travel needs to be understood in terms of its potential risks and benefits so that it can be evaluated against alternatives by patients who are seeking care. We propose three domains –quality standards, informed decision-making, economic and legal protection – in which better evidence could support the development of medical travel policies. PMID:26549906
ERIC Educational Resources Information Center
Obschonka, Martin; Silbereisen, Rainer K.; Wasilewski, Jacek
2012-01-01
Focusing on new demands posed by social and economic change, and applying a pattern-based approach, this study examined constellations of increasing labor market uncertainties (understood as threat) and increasing job-related learning tasks (understood as positive challenge). We investigated whether and how the groups of working individuals behind…
NASA Astrophysics Data System (ADS)
Krishnan, Chethan; Raju, Avinash
2017-08-01
We argue that in the tensionless phase of string theory where the stringy gauge symmetries are unbroken, (at least some) cosmological singularities can be understood as gauge artefacts. We present two conceptually related, but distinct, pieces of evidence: one relying on spacetime and the other on worldsheet.
Monitoring Bloom Dynamics of a Common Coastal Bioluminescent Ctenophore
2007-09-30
jellyfish blooms are not well understood, but are generally assumed to be a combination of physical and biological factors, with temperature and...bioluminescent jellyfish , especially of Mnemiopsis leidyi, are a common occurrence that appear to be on the rise. Evidence indicates that these blooms
Schmidt, Mathias V; Trümbach, Dietrich; Weber, Peter; Wagner, Klaus; Scharf, Sebastian H; Liebl, Claudia; Datson, Nicole; Namendorf, Christian; Gerlach, Tamara; Kühne, Claudia; Uhr, Manfred; Deussing, Jan M; Wurst, Wolfgang; Binder, Elisabeth B; Holsboer, Florian; Müller, Marianne B
2010-12-15
Increased vulnerability to aversive experiences is one of the main risk factors for stress-related psychiatric disorders as major depression. However, the molecular bases of vulnerability, on the one hand, and stress resilience, on the other hand, are still not understood. Increasing clinical and preclinical evidence suggests a central involvement of the glutamatergic system in the pathogenesis of major depression. Using a mouse paradigm, modeling increased stress vulnerability and depression-like symptoms in a genetically diverse outbred strain, and we tested the hypothesis that differences in AMPA receptor function may be linked to individual variations in stress vulnerability. Vulnerable and resilient animals differed significantly in their dorsal hippocampal AMPA receptor expression and AMPA receptor binding. Treatment with an AMPA receptor potentiator during the stress exposure prevented the lasting effects of chronic social stress exposure on physiological, neuroendocrine, and behavioral parameters. In addition, spatial short-term memory, an AMPA receptor-dependent behavior, was found to be predictive of individual stress vulnerability and response to AMPA potentiator treatment. Finally, we provide evidence that genetic variations in the AMPA receptor subunit GluR1 are linked to the vulnerable phenotype. Therefore, we propose genetic variations in the AMPA receptor system to shape individual stress vulnerability. Those individual differences can be predicted by the assessment of short-term memory, thereby opening up the possibility for a specific treatment by enhancing AMPA receptor function.
Davis, Robert T.; Simon, Jillian N.; Utter, Megan; Mungai, Paul; Alvarez, Manuel G.; Chowdhury, Shamim A.K.; Heydemann, Ahlke; Ke, Yunbo; Wolska, Beata M.; Solaro, R. John
2015-01-01
Aims Despite its known cardiovascular benefits, the intracellular signalling mechanisms underlying physiological cardiac growth remain poorly understood. Therefore, the purpose of this study was to investigate a novel role of p21-activated kinase-1 (Pak1) in the regulation of exercise-induced cardiac hypertrophy. Methods and results Wild-type (WT) and Pak1 KO mice were subjected to 6 weeks of treadmill endurance exercise training (ex-training). Cardiac function was assessed via echocardiography, in situ haemodynamics, and the pCa–force relations in skinned fibre preparations at baseline and at the end of the training regimen. Post-translational modifications to the sarcomeric proteins and expression levels of calcium-regulating proteins were also assessed following ex-training. Heart weight/tibia length and echocardiography data revealed that there was marked hypertrophy following ex-training in the WT mice, which was not evident in the KO mice. Additionally, following ex-training, WT mice demonstrated an increase in cardiac contractility, myofilament calcium sensitivity, and phosphorylation of cardiac myosin-binding protein C, cardiac TnT, and tropomyosin compared with KO mice. With ex-training in WT mice, there were also increased protein levels of calcineurin and increased phosphorylation of phospholamban. Conclusions Our data suggest that Pak1 is essential for adaptive physiological cardiac remodelling and support previous evidence that demonstrates Pak1 signalling is important for cardiac growth and survival. PMID:26464331
Diet and gastroesophageal reflux disease: role in pathogenesis and management.
Sethi, Sajiv; Richter, Joel E
2017-03-01
Gastroesophageal reflux disease (GERD) is a common disease that presents with a variety of symptoms including heartburn and acid regurgitation. Although dietary modification is currently regarded as first-line therapy for the disease, the role of diet in the pathogenesis and management of GERD is still poorly understood. The present article aims to review recent literature that examines the relationship of diet and GERD. Increased awareness of medications side effects and widespread overuse has brought nonpharmacological therapies to the forefront for the management of GERD. Recent findings have established the important role of nutrition for the managements of symptoms of GERD. Increasing scientific evidence has produced objective data on the role of certain trigger foods, whereas population studies endorse decreased reflux symptoms by following certain diets. Obesity has been linked with increased symptoms of GERD as well. Furthermore, the importance of lifestyle techniques such as head of bed elevation and increased meal to sleep time may provide nonpharmacologic methods for effective symptom control in GERD. We provide a comprehensive review on the association between diet and its role in the development and management of GERD.
The lifespan-reproduction trade-off under dietary restriction is sex-specific and context-dependent.
Adler, Margo I; Cassidy, Elizabeth J; Fricke, Claudia; Bonduriansky, Russell
2013-06-01
Adult dietary restriction (DR) extends lifespan, but the mechanisms that underlie this effect are not well understood. Many DR studies have demonstrated that lifespan extension tends to be accompanied by a reduction in female fecundity - a correlation widely interpreted as evidence that DR triggers an adaptive re - allocation of resources from reproduction to somatic maintenance. Yet, recent evidence suggests that survival and fecundity need not always trade off under DR, calling the re-allocation hypothesis into question. Because the effects of DR on both survival and reproduction have rarely been tested in both sexes, or under a range of ecologically-relevant environments, the generality of this trade-off remains unclear. We examined the effects of DR on survival and reproduction in both sexes and across a range of environments (larval diet quality and adult sex ratio) in the neriid fly Telostylinus angusticollis. We found that the lifespan-reproduction trade-off is both context- and sex-dependent. Although DR extended lifespan in both sexes by 65% and rendered females completely infertile, costs of DR on male fecundity were subtle and evident only in particular environmental combinations. Our findings suggest that a re-allocation of resources may not underlie the lifespan extension response to DR. Instead, full feeding may be associated with increased costs in comparison to DR, such that lifespan extension may be achieved without an increased resource investment to the soma. Copyright © 2013 Elsevier Inc. All rights reserved.
Guyenet, Stephan J.
2012-01-01
Context: Obesity has emerged as one of the leading medical challenges of the 21st century. The resistance of this disorder to effective, long-term treatment can be traced to the fact that body fat stores are subject to homeostatic regulation in obese individuals, just as in lean individuals. Because the growing obesity epidemic is linked to a substantial increase in daily energy intake, a key priority is to delineate how mechanisms governing food intake and body fat content are altered in an obesogenic environment. Evidence Acquisition: We considered all relevant published research and cited references that represented the highest quality evidence available. Where space permitted, primary references were cited. Evidence Synthesis: The increase of energy intake that has fueled the U.S. obesity epidemic is linked to greater availability of highly rewarding/palatable and energy-dense food. Obesity occurs in genetically susceptible individuals and involves the biological defense of an elevated body fat mass, which may result in part from interactions between brain reward and homeostatic circuits. Inflammatory signaling, accumulation of lipid metabolites, or other mechanisms that impair hypothalamic neurons may also contribute to the development of obesity and offer a plausible mechanism to explain the biological defense of elevated body fat mass. Conclusions: Despite steady research progress, mechanisms underlying the resistance to fat loss once obesity is established remain incompletely understood. Breakthroughs in this area may be required for the development of effective new obesity prevention and treatment strategies. PMID:22238401
Flavonoids, alkali earth and rare earth elements affect germination of pecan pollen
USDA-ARS?s Scientific Manuscript database
The factors regulating pecan [Carya illinoinensis (Wangenh.) K. Koch] pollen grain germination on receptive stigmatic flower surfaces in vivo or in vitro in pollen viability assays are poorly understood. While there are many potential regulating factors, there is evidence for involvement of flavonol...
Neural Correlates of Socioeconomic Status in the Developing Human Brain
ERIC Educational Resources Information Center
Noble, Kimberly G.; Houston, Suzanne M.; Kan, Eric; Sowell, Elizabeth R.
2012-01-01
Socioeconomic disparities in childhood are associated with remarkable differences in cognitive and socio-emotional development during a time when dramatic changes are occurring in the brain. Yet, the neurobiological pathways through which socioeconomic status (SES) shapes development remain poorly understood. Behavioral evidence suggests that…
Grammatical Processing in Schizophrenia: Evidence from Morphology
ERIC Educational Resources Information Center
Walenski, Matthew; Weickert, Thomas W.; Maloof, Christopher J.; Ullman, Michael T.
2010-01-01
Patients with psychiatric disorders such as schizophrenia commonly present with impaired language. Here we investigate language in schizophrenia with a focus on inflectional morphology, using an intensively studied and relatively well-understood linguistic paradigm. Patients with schizophrenia (n = 43) and age-matched healthy control subjects (n =…
Verbal Understanding and Pavlovian Processes
ERIC Educational Resources Information Center
Tonneau, François
2004-01-01
The behavioral processes through which people react appropriately to verbal descriptions remain poorly understood. I argue here that these processes are Pavlovian. Common objections to a Pavlovian account of symbolic behavior evidence a lack of familiarity with the relevant data or misunderstandings of operant theory. Although much remains to be…
The Structure of Integral Dimensions: Contrasting Topological and Cartesian Representations
ERIC Educational Resources Information Center
Jones, Matt; Goldstone, Robert L.
2013-01-01
Diverse evidence shows that perceptually integral dimensions, such as those composing color, are represented holistically. However, the nature of these holistic representations is poorly understood. Extant theories, such as those founded on multidimensional scaling or general recognition theory, model integral stimulus spaces using a Cartesian…
Direct-Access Retrieval during Sentence Comprehension: Evidence from Sluicing
ERIC Educational Resources Information Center
Martin, Andrea E.; McElree, Brian
2011-01-01
Language comprehension requires recovering meaning from linguistic form, even when the mapping between the two is indirect. A canonical example is ellipsis, the omission of information that is subsequently understood without being overtly pronounced. Comprehension of ellipsis requires retrieval of an antecedent from memory, without prior…
The Psychophysiological Mechanisms of Alexithymia in Autism Spectrum Disorder
ERIC Educational Resources Information Center
Gaigg, Sebastian B.; Cornell, Anna S. F.; Bird, Geoffrey
2018-01-01
Accumulating evidence indicates that co-occurring alexithymia underlies several facets of the social-emotional difficulties common in individuals with autism spectrum disorder. The mechanisms involved, however, remain poorly understood because measuring alexithymia relies heavily on self-report. To address this issue, carefully matched groups of…
Engaging patients in primary care practice transformation: theory, evidence and practice.
Sharma, Anjana E; Grumbach, Kevin
2017-06-01
Patient engagement is a fundamental strategy for achieving patient centred care and is receiving increasing attention in primary care reform efforts such as the patient-centred medical home and related care models. Much of the prior published theory and evidence supporting patient engagement has focused on improving engagement in individual care. Much less is understood about engaging patients as partners in practice improvement at the primary care clinic or practice level. We review the historical and policy context for the growing interest in the USA and UK in patient engagement at the primary care practice level, highlight findings from systematic reviews of the research evidence on practice-level patient engagement and discuss practical considerations for implementing patient engagement. We conclude that while there are persuasive ethical and social justice reasons for empowering patient involvement in practice improvement at the clinic level, research conducted to date in primary care provides suggestive but not yet resounding evidence in support of the instrumental triple aim benefit of practice-level patient engagement. We propose a research agenda to better understand the process and outcomes of practice-level patient engagement and its potential advantages to both the practice and the patients and communities served. Better evidence as well as resources to support and incentivize effective and feasible engagement methods are needed to catalyse greater diffusion of practice-level patient engagement in primary care practices. © The Author 2016. Published by Oxford University Press.
Robinson, Dudley; Hanna-Mitchell, Ann; Rantell, Angie; Thiagamoorthy, Gans; Cardozo, Linda
2017-04-01
There is increasing evidence that diet may have a significant role in the development of lower urinary tract symptoms. While fluid intake is known to affect lower urinary tract function the effects of alcohol, caffeine, carbonated drinks, and artificial sweeteners are less well understood and evidence from epidemiological studies is mixed and sometimes contradictory. The aim of this paper is to appraise the available evidence on the effect of caffeine, alcohol, and carbonated drinks on lower urinary tract function and dysfunction in addition to suggesting proposals for further research. Literature review based on a systematic search strategy using the terms "fluid intake," "caffeine," "alcohol," "carbonated" and "urinary incontinence," "detrusor overactivity," "Overactive Bladder," "OAB." In addition to fluid intake, there is some evidence to support a role of caffeine, alcohol, and carbonated beverages in the pathogenesis of OAB and lower urinary tract dysfunction. Although some findings are contradictory, others clearly show an association between the ingestion of caffeine, carbonated drinks, and alcohol with symptom severity. CONCLUSIONS Given the available evidence lifestyle interventions and fluid modification may have an important role in the primary prevention of lower urinary tract symptoms. However, more research is needed to determine the precise role of caffeine, carbonated drinks, and alcohol in the pathogenesis and management of these symptoms. The purpose of this paper is to stimulate that research. Neurourol. Urodynam. 36:876-881, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Gordon, Amie M; Chen, Serena
2016-02-01
Conflict can have damaging effects on relationship health. But is all conflict detrimental? Across 7 studies, we tested the overarching hypothesis that conflict in close relationships is only detrimental when people do not feel their thoughts, feelings, and point of view are understood by their relationship partners. Supporting this, conflict was negatively associated with relationship satisfaction among participants who perceived their romantic partner as less understanding, but not among those who felt more understood by their partners. This was true cross-sectionally (Study 1), experimentally (Studies 2, 3, 6a, and 6b), in daily life (Study 4), and for both members of couples pre- to postconflict conversation in the laboratory (Study 5). The buffering effects of feeling understood could not be explained by people who felt more understood being more understanding themselves, having more general positive perceptions of their partners, fighting about less important or different types of issues, engaging in more pleasant conflict conversations, or being more satisfied with their relationships before the conflict. Perceived understanding was positively associated with conflict resolution, but this did not explain the benefits of feeling understood. Evidence from Studies 6a and 6b suggests that feeling understood during conflict may buffer against reduced relationship satisfaction in part because it strengthens the relationship and signals that one's partner is invested. Overall, these studies suggest that perceived understanding may be a critical buffer against the potentially detrimental effects of relationship conflict. (c) 2016 APA, all rights reserved).
Social activity, cognitive decline and dementia risk: a 20-year prospective cohort study.
Marioni, Riccardo E; Proust-Lima, Cecile; Amieva, Helene; Brayne, Carol; Matthews, Fiona E; Dartigues, Jean-Francois; Jacqmin-Gadda, Helene
2015-10-24
Identifying modifiable lifestyle correlates of cognitive decline and risk of dementia is complex, particularly as few population-based longitudinal studies jointly model these interlinked processes. Recent methodological developments allow us to examine statistically defined sub-populations with separate cognitive trajectories and dementia risks. Engagement in social, physical, or intellectual pursuits, social network size, self-perception of feeling well understood, and degree of satisfaction with social relationships were assessed in 2854 participants from the Paquid cohort (mean baseline age 77 years) and related to incident dementia and cognitive change over 20-years of follow-up. Multivariate repeated cognitive information was exploited by defining the global cognitive functioning as the latent common factor underlying the tests. In addition, three latent homogeneous sub-populations of cognitive change and dementia were identified and contrasted according to social environment variables. In the whole population, we found associations between increased engagement in social, physical, or intellectual pursuits and increased cognitive ability (but not decline) and decreased risk of incident dementia, and between feeling understood and slower cognitive decline. There was evidence for three sub-populations of cognitive aging: fast, medium, and no cognitive decline. The social-environment measures at baseline did not help explain the heterogeneity of cognitive decline and incident dementia diagnosis between these sub-populations. We observed a complex series of relationships between social-environment variables and cognitive decline and dementia. In the whole population, factors such as increased engagement in social, physical, or intellectual pursuits were related to a decreased risk of dementia. However, in a sub-population analysis, the social-environment variables were not linked to the heterogeneous patterns of cognitive decline and dementia risk that defined the sub-groups.
Akers, R M
2017-12-01
Although peripubertal mammary development represents only a small fraction of the total mass of mammary parenchyma present in the udder at the end of gestation and into lactation, there is increasing evidence that the tissue foundations created in early life can affect future mammary development and function. Studies on expression of estrogen and progesterone receptors seem to confirm the relevance of these steroids in prepubertal mammary development, but connections with other growth factors, hormones, and local tissue factors remain elusive. Enhanced preweaning feeding in the bovine appears to enhance the capacity of mammary tissue to response to mammogenic stimulation. This suggests the possibility that improved early nutrition might allow for creation of stem or progenitor cell populations to better support the massive ductal growth and lobulo-alveolar development during gestation. Increasing evidence that immune cells are involved in mammary development suggests there are unexpected and poorly understood connections between the immune system and mammary development. This is nearly unexplored in ruminants. Development of new tools to identify, isolate, and characterize cell populations within the developing bovine mammary gland offer the possibility of identifying and perhaps altering populations of mammary stem cells or selected progenitor cells to modulate mammary development and, possibly, mammary function.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brady, Michael P.; Ievlev, Anton V.; Fayek, Mostafa
Hydrogen gas is formed when Mg corrodes in water; however, the manner and extent to which the hydrogen may also enter the Mg metal is poorly understood. Such knowledge is critical as stress corrosion cracking (SCC)/embrittlement phenomena limit many otherwise promising structural and functional uses of Mg. Here, we report via D 2O/D isotopic tracer and H 2O exposures with characterization by secondary ion mass spectrometry, inelastic neutron scattering vibrational spectrometry, electron microscopy, and atom probe tomography techniques direct evidence that hydrogen rapidly penetrated tens of micrometers into Mg metal after only 4 h of exposure to water at roommore » temperature. Further, technologically important microalloying additions of <1 wt % Zr and Nd used to improve the manufacturability and mechanical properties of Mg significantly increased the extent of hydrogen ingress, whereas Al additions in the 2–3 wt % range did not. Segregation of hydrogen species was observed at regions of high Mg/Zr/Nd nanoprecipitate density and at Mg(Zr) metastable solid solution microstructural features. We also report evidence that this ingressed hydrogen was unexpectedly present in the alloy as nanoconfined, molecular H 2. These new insights provide a basis for strategies to design Mg alloys to resist SCC in aqueous environments as well as potentially impact functional uses such as hydrogen storage where increased hydrogen uptake is desired.« less
Reduced heart rate variability in schizophrenia and bipolar disorder compared to healthy controls.
Quintana, D S; Westlye, L T; Kaufmann, T; Rustan, Ø G; Brandt, C L; Haatveit, B; Steen, N E; Andreassen, O A
2016-01-01
Despite current diagnostic systems distinguishing schizophrenia (SZ) and bipolar disorder (BD) as separate diseases, emerging evidence suggests they share a number of clinical and epidemiological features, such as increased cardiovascular disease (CVD) risk. It is not well understood if poor cardiac autonomic nervous system regulation, which can be indexed non-invasively by the calculation of heart rate variability (HRV), contributes to these common CVD risk factors in both diseases. We calculated HRV in 47 patients with SZ, 33 patients with BD and 212 healthy controls. Measures of symptom severity were also collected from the patient groups. Heart rate variability was significantly reduced in both these disorders in comparison with the healthy participants; however, there were no HRV differences between disorders. Importantly, these reductions were independent of the medication, age or body mass index effects. There was also preliminary evidence that patients with reduced HRV had increased overall and negative psychosis symptom severity regardless of SZ or BD diagnosis. We suggest that HRV may provide a possible biomarker of CVD risk and symptom severity in severe mental illness. Thus, our results highlight the importance of cardiometabolic screening across SZ and bipolar spectrum disorders. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Yang, Zhenzhen; Zhang, Yeting; Wafula, Eric K; Honaas, Loren A; Ralph, Paula E; Jones, Sam; Clarke, Christopher R; Liu, Siming; Su, Chun; Zhang, Huiting; Altman, Naomi S; Schuster, Stephan C; Timko, Michael P; Yoder, John I; Westwood, James H; dePamphilis, Claude W
2016-10-24
Horizontal gene transfer (HGT) is the transfer of genetic material across species boundaries and has been a driving force in prokaryotic evolution. HGT involving eukaryotes appears to be much less frequent, and the functional implications of HGT in eukaryotes are poorly understood. We test the hypothesis that parasitic plants, because of their intimate feeding contacts with host plant tissues, are especially prone to horizontal gene acquisition. We sought evidence of HGTs in transcriptomes of three parasitic members of Orobanchaceae, a plant family containing species spanning the full spectrum of parasitic capabilities, plus the free-living Lindenbergia Following initial phylogenetic detection and an extensive validation procedure, 52 high-confidence horizontal transfer events were detected, often from lineages of known host plants and with an increasing number of HGT events in species with the greatest parasitic dependence. Analyses of intron sequences in putative donor and recipient lineages provide evidence for integration of genomic fragments far more often than retro-processed RNA sequences. Purifying selection predominates in functionally transferred sequences, with a small fraction of adaptively evolving sites. HGT-acquired genes are preferentially expressed in the haustorium-the organ of parasitic plants-and are strongly biased in predicted gene functions, suggesting that expression products of horizontally acquired genes are contributing to the unique adaptive feeding structure of parasitic plants.
Role of cerebellum in deglutition and deglutition disorders.
Rangarathnam, Balaji; Kamarunas, Erin; McCullough, Gary H
2014-12-01
The objective of this review is to gather available evidence regarding the role of the cerebellum in swallowing-related functions. We reviewed literature on cerebellar functions related to healthy swallowing, patterns of dysphagia in individuals with cerebellar lesions, and the role of the cerebellum in therapeutic intervention of neurogenic dysphagia since 1980. A collective understanding of these studies suggests that both hemispheres of the cerebellum, predominantly the left, participate in healthy swallowing. Also, it appears that the cerebellum contributes to specific physiological functions within the entire act of swallowing, but this is not clearly understood. The understanding of patterns of dysphagia in cerebellar lesions remains ambiguous with equivocal results across a small number of studies. The cerebellum appears to be involved in oral exercises for dysphagia in the relationship between oral movements in such exercises, and deglutition remains uncertain. There is increasing evidence to suggest successful use of transcranial magnetic stimulation of the cerebellum to improve neuromotor control of swallowing. Future studies should address activation of the cerebellum with swallowing of different consistencies and tastes in healthy adults to gain better insights. Studies should also investigate dynamics of neural activation during different stages of recovery from dysphagia following strokes to cortical centers to determine if the cerebellum plays a compensatory role during instances of increased neural demands.
Langberg, Kurt; Phillips, Matthew; Rueppell, Olav
2018-04-01
The rate of genomic recombination displays evolutionary plasticity and can even vary in response to environmental factors. The western honey bee (Apis mellifera L.) has an extremely high genomic recombination rate but the mechanistic basis for this genome-wide upregulation is not understood. Based on the hypothesis that meiotic recombination and DNA damage repair share common mechanisms in honey bees as in other organisms, we predicted that oxidative stress leads to an increase in recombination rate in honey bees. To test this prediction, we subjected honey bee queens to oxidative stress by paraquat injection and measured the rates of genomic recombination in select genome intervals of offspring produced before and after injection. The evaluation of 26 genome intervals in a total of over 1750 offspring of 11 queens by microsatellite genotyping revealed several significant effects but no overall evidence for a mechanistic link between oxidative stress and increased recombination was found. The results weaken the notion that DNA repair enzymes have a regulatory function in the high rate of meiotic recombination of honey bees, but they do not provide evidence against functional overlap between meiotic recombination and DNA damage repair in honey bees and more mechanistic studies are needed.
Calcium and vitamin D in post menopausal women.
Aggarwal, Sameer; Nityanand
2013-12-01
Calcium and Vitamin D are widely used therapies for Osteoporosis. Vitamin D is not a vitamin in true sense since it is produced in response to the action of sunlight on skin. Vitamin D has multiple roles in the body, not all of them well-understood. Vitamin D supplementation must be considered a form of hormone replacement therapy. Therefore it raises all the questions about efficacy, dose, and side effects. The Efficacy of use of Calcium and Vitamin D in all post menopausal women in terms of the prevention of fracture is uncertain. The Annual worldwide sales of these supplements have been several billion dollars. The variation of the results from various studies of Calcium and Vitamin D supplementation in elderly women suggest that benefit of calcium plus vitamin D on bone mineral density or the risk of fracture is small and may vary from group to group and baseline Vitamin D status. Women taking supplemental vitamin D and calcium have a statistically increased incidence of renal stones, according to evidence from the Women's Health Initiative. Studies have shown association between calcium use and increased risk for cardiovascular disease. In a recent review of evidence from 6 randomized trials evaluating the use of vitamin D and calcium to prevent fractures in postmenopausal women who are not living in a nursing home or other institution, the United States Preventive Task Force (USPTF) found no evidence of a benefit from supplementation with 400 IU or less of vitamin D3 and 1000 mg or less of calcium. Also in a report from institute of Medicine Committee, there was insufficient evidence, particularly from randomized trials, that vitamin D treatment affected the risk of non skeletal outcomes like risk of cancer, cardiovascular disease, diabetes, infections, autoimmune disease, and other extra skeletal outcomes.
Inorganic carbon addition stimulates snow algae primary productivity
NASA Astrophysics Data System (ADS)
Hamilton, T. L.; Havig, J. R.
2017-12-01
Earth has experienced glacial/interglacial oscillations throughout its history. Today over 15 million square kilometers (5.8 million square miles) of Earth's land surface is covered in ice including glaciers, ice caps, and the ice sheets of Greenland and Antarctica, most of which are retreating as a consequence of increased atmospheric CO2. Glaciers are teeming with life and supraglacial snow and ice surfaces are often red due to blooms of photoautotrophic algae. Recent evidence suggests the red pigmentation, secondary carotenoids produced in part to thrive under high irradiation, lowers albedo and accelerates melt. However, there are relatively few studies that report the productivity of snow algae communities and the parameters that constrain their growth on snow and ice surfaces. Here, we demonstrate that snow algae primary productivity can be stimulated by the addition of inorganic carbon. We found an increase in light-dependent carbon assimilation in snow algae microcosms amended with increasing amounts of inorganic carbon. Our snow algae communities were dominated by typical cosmopolitan snow algae species recovered from Alpine and Arctic environments. The climate feedbacks necessary to enter and exit glacial/interglacial oscillations are poorly understood. Evidence and models agree that global Snowball events are accompanied by changes in atmospheric CO2 with increasing CO2 necessary for entering periods of interglacial time. Our results demonstrate a positive feedback between increased CO2 and snow algal productivity and presumably growth. With the recent call for bio-albedo effects to be considered in climate models, our results underscore the need for robust climate models to include feedbacks between supraglacial primary productivity, albedo, and atmospheric CO2.
ERIC Educational Resources Information Center
Sashittal, Hemant C.; Jassawalla, Avan R.; Markulis, Peter
2012-01-01
Apathy and social disconnectedness among undergraduate business students remain poorly understood and under-researched--despite evidence that they produce an adverse impact on learning-related outcomes. Qualitative research was initially conducted among a sample of undergraduate business students to identify the antecedents and learning-related…
Evolution of Management Thought in the Ancient Times.
ERIC Educational Resources Information Center
Sharma, C. L.
This paper argues that although systematic management thought is a distinctly modern development, the writings of ancient scholars and records of ancient rulers infer that they understood the rudiments of management principles and concepts. To support this thesis, the author reviews the evidence of management practices and concepts in various…
The Dreaming Child: Dreams, Religion and Religious Education
ERIC Educational Resources Information Center
Adams, Kate
2008-01-01
Dreaming is an integral part of human life. Whilst psychology has generated extensive knowledge and understanding about dreams, it was in religious contexts that they were originally understood. This relationship between dreams and religion is still evident in contemporary society in the scriptures of the Abrahamic faiths, which narrate dreams…
Structure and pragmatics in informal argument: circularity and question-begging.
Brem, Sarah K.
2003-04-01
Most everyday arguments are informal, as contrasted with the formal arguments of logic and mathematics. Whereas formal argument is well understood, the nature of informal argument is more elusive. A recent study by Rips (2002) provides further evidence regarding the roles of structure and pragmatics in informal argument.
Coping Mediates the Association between Gender and Depressive Symptomatology in Adolescence
ERIC Educational Resources Information Center
Malooly, Ashley M.; Flannery, Kaitlin M.; Ohannessian, Christine McCauley
2017-01-01
Previous studies have found evidence for gender and racial/ethnic differences in depressive symptoms in adolescence; however, the mechanisms driving this relationship are poorly understood. The goal of this study was to examine the role of individual differences in dispositional coping in the relationships between gender and depressive…
The Pragmatics of Color in Antara's Poetry
ERIC Educational Resources Information Center
Btoosh, Mousa A.
2014-01-01
Perhaps rarely is there any piece of Pre-Islamic Arabic literature where color features more strongly and less naturally than in Antara's poetry. Therefore, the intended message of color in Antara's poetry is adequately understood inasmuch as the pragmatic implicatures of color are worked out. Evidence in literature explicitly attributes Antara's…
Biogeochemistry of uranium in wetlands plays important roles in U immobilization in storage ponds of U mining and processing facilities but has not been well understood. The objective of this work was to study molecular mechanisms responsible for high U retention by Savannah Ri...
Orienting to Topic in Clinical Discourse Elicitation of Everyday Conversation
ERIC Educational Resources Information Center
Fond, Marissa Joanne
2013-01-01
Talking topically, as it is understood intuitively and evoked metadiscursively, requires constructing an intersubjective orientation to talk that must be continually renewed. Analysis of interactants' ability to orient to topic emergence provides evidence of what is achieved in interaction, as well as why conversational coordination can lapse…
Thinking Critically about Critical Thinking in Higher Education
ERIC Educational Resources Information Center
Lloyd, Margaret; Bahr, Nan
2010-01-01
The literature on critical thinking in higher education is constructed around the fundamental assumption that, while regarded as essential, is neither clearly nor commonly understood. There is elsewhere evidence that academics and students have differing perceptions of what happens in university classrooms, particularly in regard to higher order…
USDA-ARS?s Scientific Manuscript database
Deficit irrigation reduces seasonal carbohydrate supply and decreases starch concentrations in vegetative tissues. The specific role of starch metabolism in conferring tolerance to cold is still poorly understood. A decrease in cold tolerance after sequential years of deficit irrigation would limit ...
The Multidimensionality of Child Poverty: Evidence from Afghanistan
ERIC Educational Resources Information Center
Trani, Jean-Francois; Biggeri, Mario; Mauro, Vincenzo
2013-01-01
This paper examines multidimensional poverty among children in Afghanistan using the Alkire-Foster method. Several previous studies have underlined the need to separate children from their adult nexus when studying poverty and treat them according to their own specificities. From the capability approach, child poverty is understood to be the lack…
Dysarthria and Friedreich's Ataxia: What Can Intelligibility Assessment Tell Us?
ERIC Educational Resources Information Center
Blaney, Bronagh; Hewlett, Nigel
2007-01-01
Background: Friedreich's ataxia is one of the most common hereditary disorders of the nervous system. Dysarthria is a pervasive symptom of Friedreich's ataxia, yet the clinical presentation of speech symptoms remains poorly understood, leaving clinicians without the evidence required to develop therapy interventions. Aims: The research reported…
USDA-ARS?s Scientific Manuscript database
Epidemiological evidence implicates diets rich in fruits and vegetables in breast cancer prevention due to their phytochemical components, yet mechanisms for their anti-tumor activities are not well-understood. A small population of mammary epithelial cells, termed cancer stem cells (CSC), may be re...
Depression and Relational Health in Asian American and European American College Women
ERIC Educational Resources Information Center
Lund, Terese J.; Chan, Pauline; Liang, Belle
2014-01-01
Research consistently demonstrates elevated rates of depression among college-aged women, yet evidence of racial differences in depression among this population are poorly understood. Moreover, the correlates of depression among Asian American women are also understudied. In this exploratory analysis, we examined mean differences in depression…
Embodied Simulations Are Modulated by Sentential Perspective
ERIC Educational Resources Information Center
van Dam, Wessel O.; Desai, Rutvik H.
2017-01-01
There is considerable evidence that language comprehenders derive lexical-semantic meaning by mentally simulating perceptual and motor attributes of described events. However, the nature of these simulations--including the level of detail that is incorporated and contexts under which simulations occur--is not well understood. Here, we examine the…
Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex
The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampl...
Identifying physical activity gender differences among youth
USDA-ARS?s Scientific Manuscript database
Physical activity (PA) is an important part of a healthy lifestyle and reduces risk of certain chronic diseases. Many youth do not currently meet PA guidelines; evidence suggests that girls are less active than boys are at all ages. PA differences need to be understood, so that gender-specific inter...
The history of the idea of allergy.
Igea, J M
2013-08-01
About 100 years ago, a young paediatrician understood that the function of the immune system should be rationalized not in terms of exemption of disease but in terms of change of reactivity. He coined a new word to represent such an idea: 'allergy': the first contact of the immune system with an antigen changes the reactivity of the individual; on the second and subsequent contacts, this change (or allergy) can induce a spectrum of responses from protective (literally, immune) to hypersensitivity ones. The idea was at first hardly understood by the scientific community because it undermined the essentially protective nature of the immune response as it was defined. Nevertheless, in the next years, the growing clinical evidence led to the acceptance of this new point of view, but not of the new word, at least not unconditionally. The original significance of the neologism 'allergy' became perverted and limited to describe hypersensitivity conditions. Perhaps because of the corruption of the term, today 'allergy' does not have a well-delimited significance among health professionals. Furthermore, the word has long ago escaped from physicians and gone to the streets, where it is popularly used also as synonymous with antipathy and rejection. This vulgarization of the term 'allergy' has significantly increased its imprecision. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Inhaled corticosteroids and the increased risk of pneumonia: what’s new? A 2015 updated review
Iannella, Hernan; Luna, Carlos; Waterer, Grant
2016-01-01
There is a considerable amount of evidence that supports the possibility of an increased risk of pneumonia associated with prolonged use of inhaled corticosteroids (ICS) in patients with chronic obstructive pulmonary disease (COPD). However, as yet, no statistically significant increase in pneumonia-related 30-day mortality in patients on ICS has been demonstrated. The lack of objective pneumonia definitions and radiological confirmations have been a major source of bias, because of the similarities in clinical presentation between pneumonia and acute exacerbations of COPD. One of the newer fluticasone furoate studies overcomes these limitations and also provides an assessment of a range of doses, suggesting that the therapeutic window is quite narrow and that conventional dosing has probably been too high, although the absolute risk may be different compared to other drugs. Newer studies were not able to rule out budesonide as responsible for pneumonia, as previous evidence suggested, and there is still need for evidence from head-to-head comparisons in order to better assess possible intra-class differences. Although the exact mechanisms by which ICS increase the risk of pneumonia are not fully understood, the immunosuppressive effects of ICS on the respiratory epithelium and the disruption of the lung microbiome are most likely to be implicated. Given that COPD represents such a complex and heterogeneous disease, attempts are being made to identify clinical phenotypes with clear therapeutic implications, in order to optimize the pharmacological treatment of COPD and avoid the indiscriminate use of ICS. If deemed necessary, gradual withdrawal of ICS appears to be well tolerated. Vaccination against pneumococcus and influenza should be emphasized in patients with COPD receiving ICS. Physicians should keep in mind that signs and symptoms of pneumonia in COPD patients may be initially indistinguishable from those of an exacerbation, and that patients with COPD appear to be at increased risk of developing pneumonia as a complication of ICS therapy. PMID:26893311
Towards a framework for preventing community violence among youth.
Abt, Thomas P
2017-03-01
This article, in an effort to assist the selection and deployment of evidence-informed strategies, proposes a new conceptual framework for responding to community violence among youth. First, the phenomenon of community violence is understood in context using a new violence typology organized along a continuum. Second, the need for a new anti-community violence framework is established. Third, a framework is developed, blending concepts from the fields of public safety and public health. Fourth, evidence from systematic reviews and meta-analyses concerning community violence is summarized and categorized. Finally, an anti-violence framework populated with evidence-informed strategies is presented and discussed.
Costa-Ferreira, Willian; Vieira, Jonas O; Almeida, Jeferson; Gomes-de-Souza, Lucas; Crestani, Carlos C
2016-01-01
Consistent evidence has shown an important role of emotional stress in pathogenesis of cardiovascular diseases. Additionally, studies in animal models have demonstrated that daily exposure to different stressor (heterotypic stressor) evokes more severe changes than those resulting from repeated exposure to the same aversive stimulus (homotypic stressor), possibly due to the habituation process upon repeated exposure to the same stressor. Despite these pieces of evidence, the mechanisms involved in the stress-evoked cardiovascular dysfunction are poorly understood. Therefore, the present study investigated the involvement of angiotensin II (Ang II) acting on the type 1 Ang II receptor (AT1) in the cardiovascular dysfunctions evoked by both homotypic and heterotypic chronic emotional stresses in rats. For this purpose, we compared the effect of the chronic treatment with the AT1 receptor antagonist losartan (30 mg/kg/day, p.o.) on the cardiovascular and autonomic changes evoked by the heterotypic stressor chronic variable stress (CVS) and the homotypic stressor repeated restraint stress (RRS). RRS increased the sympathetic tone to the heart and decreased the cardiac parasympathetic activity, whereas CVS decreased the cardiac parasympathetic activity. Additionally, both stressors impaired the baroreflex function. Alterations in the autonomic activity and the baroreflex impairment were inhibited by losartan treatment. Additionally, CVS reduced the body weight and increased the circulating corticosterone; however, these effects were not affected by losartan. In conclusion, these findings indicate the involvement of angiotensin II/AT1 receptors in the autonomic changes evoked by both homotypic and heterotypic chronic stressors. Moreover, the present results provide evidence that the increase in the circulating corticosterone and body weight reduction evoked by heterotypic stressors are independent of AT1 receptors.
Reassessing immune control of hepatitis A virus.
Walker, Christopher M; Feng, Zongdi; Lemon, Stanley M
2015-04-01
There is renewed interest in hepatitis A virus (HAV) pathogenesis and immunity after 2-3 decades of limited progress. From a public health perspective, the average age at infection has increased in developing countries, resulting in more severe hepatitis that is poorly understood mechanistically. More fundamentally, there is interest in comparing immunity to HAV and hepatitis C virus (HCV): small, positive-strand RNA viruses with very different infection outcomes. Here, we review evidence that circulating HAV virions are cloaked in membranes, with consequences for induction of innate immunity and antibody-mediated neutralization. We also consider the contribution of CD4+ helper versus CD8+ cytotoxic T cells to antiviral immunity and liver injury, and present a model of non-cytotoxic immune control of HAV infection. Copyright © 2015 Elsevier B.V. All rights reserved.
Health benefits of fermented foods: microbiota and beyond.
Marco, Maria L; Heeney, Dustin; Binda, Sylvie; Cifelli, Christopher J; Cotter, Paul D; Foligné, Benoit; Gänzle, Michael; Kort, Remco; Pasin, Gonca; Pihlanto, Anne; Smid, Eddy J; Hutkins, Robert
2017-04-01
Fermented foods and beverages were among the first processed food products consumed by humans. The production of foods such as yogurt and cultured milk, wine and beer, sauerkraut and kimchi, and fermented sausage were initially valued because of their improved shelf life, safety, and organoleptic properties. It is increasingly understood that fermented foods can also have enhanced nutritional and functional properties due to transformation of substrates and formation of bioactive or bioavailable end-products. Many fermented foods also contain living microorganisms of which some are genetically similar to strains used as probiotics. Although only a limited number of clinical studies on fermented foods have been performed, there is evidence that these foods provide health benefits well-beyond the starting food materials. Copyright © 2016 Elsevier Ltd. All rights reserved.
Your Morals Depend on Language
Costa, Albert; Foucart, Alice; Hayakawa, Sayuri; Aparici, Melina; Apesteguia, Jose; Heafner, Joy; Keysar, Boaz
2014-01-01
Should you sacrifice one man to save five? Whatever your answer, it should not depend on whether you were asked the question in your native language or a foreign tongue so long as you understood the problem. And yet here we report evidence that people using a foreign language make substantially more utilitarian decisions when faced with such moral dilemmas. We argue that this stems from the reduced emotional response elicited by the foreign language, consequently reducing the impact of intuitive emotional concerns. In general, we suggest that the increased psychological distance of using a foreign language induces utilitarianism. This shows that moral judgments can be heavily affected by an orthogonal property to moral principles, and importantly, one that is relevant to hundreds of millions of individuals on a daily basis. PMID:24760073
Cytokines in Bipolar Disorder: Paving the Way for Neuroprogression
Barbosa, Izabela Guimarães; Bauer, Moisés Evandro; Machado-Vieira, Rodrigo; Teixeira, Antonio Lucio
2014-01-01
Bipolar disorder (BD) is a severe, chronic, and recurrent psychiatric illness. It has been associated with high prevalence of medical comorbidities and cognitive impairment. Its neurobiology is not completely understood, but recent evidence has shown a wide range of immune changes. Cytokines are proteins involved in the regulation and the orchestration of the immune response. We performed a review on the involvement of cytokines in BD. We also discuss the cytokines involvement in the neuroprogression of BD. It has been demonstrated that increased expression of cytokines in the central nervous system in postmortem studies is in line with the elevated circulating levels of proinflammatory cytokines in BD patients. The proinflammatory profile and the immune imbalance in BD might be regarded as potential targets to the development of new therapeutic strategies. PMID:25313338
How will melting of ice affect volcanic hazards in the twenty-first century?
Tuffen, Hugh
2010-05-28
Glaciers and ice sheets on many active volcanoes are rapidly receding. There is compelling evidence that melting of ice during the last deglaciation triggered a dramatic acceleration in volcanic activity. Will melting of ice this century, which is associated with climate change, similarly affect volcanic activity and associated hazards? This paper provides a critical overview of the evidence that current melting of ice will increase the frequency or size of hazardous volcanic eruptions. Many aspects of the link between ice recession and accelerated volcanic activity remain poorly understood. Key questions include how rapidly volcanic systems react to melting of ice, whether volcanoes are sensitive to small changes in ice thickness and how recession of ice affects the generation, storage and eruption of magma at stratovolcanoes. A greater frequency of collapse events at glaciated stratovolcanoes can be expected in the near future, and there is strong potential for positive feedbacks between melting of ice and enhanced volcanism. Nonetheless, much further research is required to remove current uncertainties about the implications of climate change for volcanic hazards in the twenty-first century.
Presence and Risk Factors for Glaucoma in Patients with Diabetes
Song, Brian J.; Aiello, Lloyd Paul; Pasquale, Louis R.
2017-01-01
Diabetes mellitus represents a growing international public health issue with a near quadrupling in its worldwide prevalence since 1980. Though it has many known microvascular complications, vision loss from diabetic retinopathy is one of the most devastating for affected individuals. In addition, there is increasing evidence to suggest that diabetic patients have a greater risk for glaucoma as well. Though the pathophysiology of glaucoma is not completely understood, both diabetes and glaucoma appear to share some common risk factors and pathophysiologic similarities with studies also reporting that the presence of diabetes and elevated fasting glucose levels are associated with elevated intraocular pressure – the primary risk factor for glaucomatous optic neuropathy. While no study has completely addressed the possibility of detection bias, most recent epidemiologic evidence suggests that diabetic populations are likely enriched with glaucoma patients. As the association between diabetes and glaucoma becomes better-defined, routine evaluation for glaucoma in diabetic patients, particularly in the telemedicine setting, may become a reasonable consideration to reduce the risk of vision loss in these patients. PMID:27766584
New insights into the pathophysiology of post-stroke spasticity.
Li, Sheng; Francisco, Gerard E
2015-01-01
Spasticity is one of many consequences after stroke. It is characterized by a velocity-dependent increase in resistance during passive stretch, resulting from hyperexcitability of the stretch reflex. The underlying mechanism of the hyperexcitable stretch reflex, however, remains poorly understood. Accumulated experimental evidence has supported supraspinal origins of spasticity, likely from an imbalance between descending inhibitory and facilitatory regulation of spinal stretch reflexes secondary to cortical disinhibition after stroke. The excitability of reticulospinal (RST) and vestibulospinal tracts (VSTs) has been assessed in stroke survivors with spasticity using non-invasive indirect measures. There are strong experimental findings that support the RST hyperexcitability as a prominent underlying mechanism of post-stroke spasticity. This mechanism can at least partly account for clinical features associated with spasticity and provide insightful guidance for clinical assessment and management of spasticity. However, the possible role of VST hyperexcitability cannot be ruled out from indirect measures. In vivo measure of individual brainstem nuclei in stroke survivors with spasticity using advanced fMRI techniques in the future is probably able to provide direct evidence of pathogenesis of post-stroke spasticity.
New insights into the pathophysiology of post-stroke spasticity
Li, Sheng; Francisco, Gerard E.
2015-01-01
Spasticity is one of many consequences after stroke. It is characterized by a velocity-dependent increase in resistance during passive stretch, resulting from hyperexcitability of the stretch reflex. The underlying mechanism of the hyperexcitable stretch reflex, however, remains poorly understood. Accumulated experimental evidence has supported supraspinal origins of spasticity, likely from an imbalance between descending inhibitory and facilitatory regulation of spinal stretch reflexes secondary to cortical disinhibition after stroke. The excitability of reticulospinal (RST) and vestibulospinal tracts (VSTs) has been assessed in stroke survivors with spasticity using non-invasive indirect measures. There are strong experimental findings that support the RST hyperexcitability as a prominent underlying mechanism of post-stroke spasticity. This mechanism can at least partly account for clinical features associated with spasticity and provide insightful guidance for clinical assessment and management of spasticity. However, the possible role of VST hyperexcitability cannot be ruled out from indirect measures. In vivo measure of individual brainstem nuclei in stroke survivors with spasticity using advanced fMRI techniques in the future is probably able to provide direct evidence of pathogenesis of post-stroke spasticity. PMID:25914638
JUGDAOHSINGH, R.
2009-01-01
Low bone mass (osteoporosis) is a silent epidemic of the 21st century, which presently in the UK results in over 200,000 fractures annually at a cost of over one billion pounds. Figures are set to increase worldwide. Understanding the factors which affect bone metabolism is thus of primary importance in order to establish preventative measures or treatments for this condition. Nutrition is an important determinant of bone health, but the effects of the individual nutrients and minerals, other than calcium, is little understood. Accumulating evidence over the last 30 years strongly suggest that dietary silicon is beneficial to bone and connective tissue health and we recently reported strong positive associations between dietary Si intake and bone mineral density in US and UK cohorts. The exact biological role(s) of silicon in bone health is still not clear, although a number of possible mechanisms have been suggested, including the synthesis of collagen and/or its stabilization, and matrix mineralization. This review gives an overview of this naturally occurring dietary element, its metabolism and the evidence of its potential role in bone health. PMID:17435952
Gribenko, Alexey V; Keiffer, Timothy R; Makhatadze, George I
2006-08-01
The heat capacity change upon unfolding (deltaC(p)) is a thermodynamic parameter that defines the temperature dependence of the thermodynamic stability of proteins; however, physical basis of the heat capacity change is not completely understood. Although empirical surface area-based calculations can predict heat capacity changes reasonably well, accumulating evidence suggests that changes in hydration of those surfaces is not the only parameter contributing to the observed heat capacity changes upon unfolding. Because packing density in the protein interior is similar to that observed in organic crystals, we hypothesized that changes in protein dynamics resulting in increased rigidity of the protein structure might contribute to the observed heat capacity change upon unfolding. Using differential scanning calorimetry we characterized the thermodynamic behavior of a serine protease inhibitor eglin C and two eglin C variants with altered native state dynamics, as determined by NMR. We found no evidence of changes in deltaC(p) in either of the variants, suggesting that changes in rigidity do not contribute to the heat capacity change upon unfolding in this model system. Copyright 2006 Wiley-Liss, Inc.
Epigenetic regulation of miRNA-Cancer Stem Cells nexus by Nutraceuticals
Ahmad, Aamir; Li, Yiwei; Bao, Bin; Kong, Dejuan; Sarkar, Fazlul H.
2014-01-01
Nutraceuticals, the bioactive food components represented by many naturally occurring dietary compounds, have been investigated for a few decades for their numerous beneficial effects, including their anticancer properties. The initial interest in the cancer-preventing/therapeutic ability of these agents was based on their ability to affect multiple signaling pathways that are deregulated in cancer cells. With a shift in the focus of cancer research to the emerging areas such as epigenetic regulation, microRNAs (miRNAs) and the cancer stem cells (CSCs), nutraceuticals initially appeared out of place. However, research investigations over the last several years have slowly but firmly presented evidence that supports a relevance of these agents in modern day research. While nutraceuticals are increasingly being realized to alter miRNA/CSCs expression and function, the molecular mechanism(s) are not very clearly understood. Epigenetic regulation is one mechanism by which these agents exert their anticancer effects. In this focused mini review, we summarize our current understanding of epigenetic regulation of miRNAs and CSCs by nutraceuticals. We discuss both direct and indirect evidences that support such an activity of these compounds. PMID:24272883
De Vito, David; Fenske, Mark J
2017-05-01
Potentially distracting or otherwise-inappropriate stimuli, thoughts, or actions often must be inhibited to prevent interference with goal-directed behaviour. Growing evidence suggests that the impact of inhibition is not limited to reduced neurocognitive processing, but also includes negative affective consequences for any associated stimuli. The link between inhibition and aversive response has primarily been studied using tasks involving attentional- or response-related inhibition of external sensory stimuli. Here we show that affective devaluation also occurs when inhibition is applied to fully-encoded stimulus representations in memory. We first replicated prior findings of increased forgetting of words whose memories were suppressed in a Think/No-think procedure (Experiment 1). Incorporating a stimulus-evaluation task within this procedure revealed that suppressing memories of words (Experiment 2) and visual objects (Experiment 3) also results in their affective devaluation. Given the critical role of memory for guiding thoughts and actions, these results suggest that the affective consequences of inhibition may occur across a far broader range of situations than previously understood. Copyright © 2017 Elsevier B.V. All rights reserved.
Martian paleolakes and waterways: Exobiological implications
Scott, D.H.; Rice, J. W.; Dohm, J.M.
1991-01-01
The problems of how warm and wet Mars once was and when climate transitions may have occurred are not well understood. Mars may have had an early environment similar to Earth's that was conductive to the ermergence of life. In addition, increasing geologic evidence indicates that water, upon which terrestrial life depends, has been present on Mars throughout its history. This evidence suggests that life could have developed not only on early Mars but also over longer periods of time in longer lasting, more clement local environments. Indications of past or present life most likely would be found in areas where liquid water existed in sufficient quantities to provide for the needs of biological systems. We suggest that paleolakes may have provided such environments. Unlike the case on Earth, this record of the origin and evolution of life has probably not been erased by extensive deformation of the Martian surface. Our work has identified eleven prospective areas where large lacustrine basins may once have existed. These areas are important for future biological, geological, and climatological investigations. ?? 1991 Kluwer Academic Publishers.
Healthcare-associated infections in Australia: time for national surveillance.
Russo, Philip L; Cheng, Allen C; Richards, Michael; Graves, Nicholas; Hall, Lisa
2015-02-01
Healthcare-associated infection (HAI) surveillance programs are critical for infection prevention. Australia does not have a comprehensive national HAI surveillance program. The purpose of this paper is to provide an overview of established international and Australian statewide HAI surveillance programs and recommend a pathway for the development of a national HAI surveillance program in Australia. This study examined existing HAI surveillance programs through a literature review, a review of HAI surveillance program documentation, such as websites, surveillance manuals and data reports and direct contact with program representatives. Evidence from international programs demonstrates national HAI surveillance reduces the incidence of HAIs. However, the current status of HAI surveillance activity in Australian states is disparate, variation between programs is not well understood, and the quality of data currently used to compose national HAI rates is uncertain. There is a need to develop a well-structured, evidence-based national HAI program in Australia to meet the increasing demand for validated reliable national HAI data. Such a program could be leveraged off the work of existing Australian and international programs.
Network analysis for a network disorder: The emerging role of graph theory in the study of epilepsy.
Bernhardt, Boris C; Bonilha, Leonardo; Gross, Donald W
2015-09-01
Recent years have witnessed a paradigm shift in the study and conceptualization of epilepsy, which is increasingly understood as a network-level disorder. An emblematic case is temporal lobe epilepsy (TLE), the most common drug-resistant epilepsy that is electroclinically defined as a focal epilepsy and pathologically associated with hippocampal sclerosis. In this review, we will summarize histopathological, electrophysiological, and neuroimaging evidence supporting the concept that the substrate of TLE is not limited to the hippocampus alone, but rather is broadly distributed across multiple brain regions and interconnecting white matter pathways. We will introduce basic concepts of graph theory, a formalism to quantify topological properties of complex systems that has recently been widely applied to study networks derived from brain imaging and electrophysiology. We will discuss converging graph theoretical evidence indicating that networks in TLE show marked shifts in their overall topology, providing insight into the neurobiology of TLE as a network-level disorder. Our review will conclude by discussing methodological challenges and future clinical applications of this powerful analytical approach. Copyright © 2015 Elsevier Inc. All rights reserved.
Climate change, aeroallergens, and pediatric allergic disease.
Sheffield, Perry E; Weinberger, Kate R; Kinney, Patrick L
2011-01-01
The degree to which aeroallergens are contributing to the global increase in pediatric allergic disease is incompletely understood. We review the evidence that links climate change to changes in aeroallergens such as pollen and outdoor mold concentrations and, subsequently, aeroallergen association with pediatric allergic disease. We specifically explore the evidence on both the exacerbation and the development of allergic disease in children related to outdoor pollen and mold concentrations. Pediatric allergic diseases include atopic dermatitis or eczema, allergic rhinitis or hay fever, and some types of asthma in children, typically defined as < 18 years of age. We discuss how the timing of aeroallergen exposure both in utero and in childhood could be associated with allergies. We conclude that the magnitude and type of health impacts due to climate change will depend on improved understanding of the relationship between climatic variables, multiple allergen factors, and allergic disease. Improved public-health strategies such as adequate humidity control, optimum air filtration and ventilation, and improved anticipatory public-health messaging will be critical to adaptation. © 2011 Mount Sinai School of Medicine.
Paleolakes and lacustrine basins on Mars
NASA Technical Reports Server (NTRS)
Scott, David H.; Rice, James W., Jr.; Dohm, James M.
1991-01-01
The problems of how warm and wet Mars once was and when climate transitions may have occurred are not well understood. Mars may have had an early environment similar to Earth's that was conducive to the emergence of life. In addition, increasing geologic evidence indicates that water, upon which terrestrial life depends, has been present on Mars throughout its history. This evidence does not detract from the possibility that life may have originated on early Mars, but rather suggests that life could have developed over longer periods of time in longer lasting, more clement local environments than previously envisioned. It is suggested herein that such environments may have been provided by paleolakes, located mostly in the northern lowlands and probably ice covered. Such lakes probably would have had diverse origins. Glacial lakes may have occupied ice eroded hollows or formed in valleys obstructed by moraines or ice barriers. Unlike Earth, the Martian record of the origin and evolution of possible life may have not been erased by extensive deformation of the surface. Thus the basins that may have contained the paleolakes are potential sites for future biological, geological, and climatological study.
'Only connect': the case for public health humanities.
Saffran, Lise
2014-12-01
Humanities in health has until now been primarily understood to mean humanities in medicine and has generally failed to include public health. I will argue in this paper that the common justifications for the former--including increased empathy among practitioners--are at least as applicable, if not more, to the latter. Growing emphasis on the social determinants of health and cultural competency in public health require public health students and professionals to develop a nuanced understanding of the influence of social context on health behaviour and to empathise with people in difficult circumstances. Literary fiction has been demonstrated to have an impact on skills related to empathy and social intelligence. Further, translating epidemiological evidence into public policy is a core task of public health and there is a growing body of research to indicate that statistical evidence is more persuasive when combined with narrative evidence. In this article I explore similarities and differences between proposed humanities in public health and programmes in humanities in medicine and highlight research gaps and possible implications of a more expansive view of humanities in health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Genetics of Tinnitus: An Emerging Area for Molecular Diagnosis and Drug Development
Lopez-Escamez, Jose A.; Bibas, Thanos; Cima, Rilana F. F.; Van de Heyning, Paul; Knipper, Marlies; Mazurek, Birgit; Szczepek, Agnieszka J.; Cederroth, Christopher R.
2016-01-01
Subjective tinnitus is the perception of sound in the absence of external or bodily-generated sounds. Chronic tinnitus is a highly prevalent condition affecting over 70 million people in Europe. A wide variety of comorbidities, including hearing loss, psychiatric disorders, neurodegenerative disorders, and temporomandibular joint (TMJ) dysfunction, have been suggested to contribute to the onset or progression of tinnitus; however, the precise molecular mechanisms of tinnitus are not well understood and the contribution of genetic and epigenetic factors remains unknown. Human genetic studies could enable the identification of novel molecular therapeutic targets, possibly leading to the development of novel pharmaceutical therapeutics. In this article, we briefly discuss the available evidence for a role of genetics in tinnitus and consider potential hurdles in designing genetic studies for tinnitus. Since multiple diseases have tinnitus as a symptom and the supporting genetic evidence is sparse, we propose various strategies to investigate the genetic underpinnings of tinnitus, first by showing evidence of heritability using concordance studies in twins, and second by improving patient selection according to phenotype and/or etiology in order to control potential biases and optimize genetic data output. The increased knowledge resulting from this endeavor could ultimately improve the drug development process and lead to the preventive or curative treatment of tinnitus. PMID:27594824
Ammerman, Seth
2014-04-01
Marijuana use in pediatric populations remains an ongoing concern, and marijuana use by adolescents had known medical, psychological, and cognitive side effects. Marijuana alters brain development and has detrimental effects on brain structure and function in ways that are incompletely understood at this point in time. Furthermore, marijuana smoke contains tar and other harmful chemicals, so marijuana cannot be recommended by physicians. At this time, no studies suggest a benefit of marijuana use by children and adolescents. In the context of limited but clear evidence showing harm or potential harm from marijuana use by adolescents, any recommendations for medical marijuana use by adolescents are based on research studies with adults and on anecdotal evidence. Criminal prosecution for marijuana possession adversely affects hundreds of thousands of youth yearly in the United States, particularly minority youth. Current evidence does not support a focus on punishment for youth who use marijuana. Rather, drug education and treatment programs should be encouraged to better help youth who are experimenting with or are dependent on marijuana. Decriminalization of recreational use of marijuana by adults has not led to an increase in youth use rates of recreational marijuana. Thus, decriminalization may be a reasonable alternative to outright criminalization, as long as it is coupled with drug education and treatment programs. The effect of outright legalization of adult recreational use of marijuana on youth use is unknown.
Pittenger, Christopher; Bloch, Michael H.; Williams, Kyle
2011-01-01
Obsessive compulsive disorder is prevalent, disabling, incompletely understood, and often resistant to current therapies. Established treatments consist of specialized cognitive-behavioral psychotherapy and pharmacotherapy with medications targeting serotonergic and dopaminergic neurotransmission. However, remission is rare, and more than a quarter of OCD sufferers receive little or no benefit from these approaches, even when they are optimally delivered. New insights into the disorder, and new treatment strategies, are urgently needed. Recent evidence suggests that the ubiquitous excitatory neurotransmitter glutamate is dysregulated in OCD, and that this dysregulation may contribute to the pathophysiology of the disorder. Here we review the current state of this evidence, including neuroimaging studies, genetics, neurochemical investigations, and insights from animal models. Finally, we review recent findings from small clinical trials of glutamate-modulating medications in treatment-refractory OCD. The precise role of glutamate dysregulation in OCD remains unclear, and we lack blinded, well-controlled studies demonstrating therapeutic benefit from glutamate-modulating agents. Nevertheless, the evidence supporting some important perturbation of glutamate in the disorder is increasingly strong. This new perspective on the pathophysiology of OCD, which complements the older focus on monoaminergic neurotransmission, constitutes an important focus of current research and a promising area for the ongoing development of new therapeutics. PMID:21963369
Navigating Into the Future or Driven by the Past.
Seligman, Martin E P; Railton, Peter; Baumeister, Roy F; Sripada, Chandra
2013-03-01
Prospection (Gilbert & Wilson, 2007), the representation of possible futures, is a ubiquitous feature of the human mind. Much psychological theory and practice, in contrast, has understood human action as determined by the past and viewed any such teleology (selection of action in light of goals) as a violation of natural law because the future cannot act on the present. Prospection involves no backward causation; rather, it is guidance not by the future itself but by present, evaluative representations of possible future states. These representations can be understood minimally as "If X, then Y" conditionals, and the process of prospection can be understood as the generation and evaluation of these conditionals. We review the history of the attempt to cast teleology out of science, culminating in the failures of behaviorism and psychoanalysis to account adequately for action without teleology. A wide range of evidence suggests that prospection is a central organizing feature of perception, cognition, affect, memory, motivation, and action. The authors speculate that prospection casts new light on why subjectivity is part of consciousness, what is "free" and "willing" in "free will," and on mental disorders and their treatment. Viewing behavior as driven by the past was a powerful framework that helped create scientific psychology, but accumulating evidence in a wide range of areas of research suggests a shift in framework, in which navigation into the future is seen as a core organizing principle of animal and human behavior. © The Author(s) 2013.
Ye, M; Yang, W; Ainscough, J F; Hu, X-P; Li, X; Sedo, A; Zhang, X-H; Zhang, X; Chen, Z; Li, X-M; Beech, D J; Sivaprasadarao, A; Luo, J-H; Jiang, L-H
2014-01-01
Transient ischemia is a leading cause of cognitive dysfunction. Postischemic ROS generation and an increase in the cytosolic Zn2+ level ([Zn2+]c) are critical in delayed CA1 pyramidal neuronal death, but the underlying mechanisms are not fully understood. Here we investigated the role of ROS-sensitive TRPM2 (transient receptor potential melastatin-related 2) channel. Using in vivo and in vitro models of ischemia–reperfusion, we showed that genetic knockout of TRPM2 strongly prohibited the delayed increase in the [Zn2+]c, ROS generation, CA1 pyramidal neuronal death and postischemic memory impairment. Time-lapse imaging revealed that TRPM2 deficiency had no effect on the ischemia-induced increase in the [Zn2+]c but abolished the cytosolic Zn2+ accumulation during reperfusion as well as ROS-elicited increases in the [Zn2+]c. These results provide the first evidence to show a critical role for TRPM2 channel activation during reperfusion in the delayed increase in the [Zn2+]c and CA1 pyramidal neuronal death and identify TRPM2 as a key molecule signaling ROS generation to postischemic brain injury. PMID:25429618
DeBoer, Mark D.; Lima, Aldo A. M.; Oría, Reinaldo B.; Scharf, Rebecca J.; Moore, Sean R.; Luna, Max A.; Guerrant, Richard L.
2012-01-01
Hypotheses regarding the developmental origins of health and disease postulate that developing fetuses–and potentially young children—undergo adaptive epigenetic changes with longstanding effects on metabolism and other processes. Ongoing research explores whether these adaptations occur during early life following malnutrition. In the developing world there remains a high degree of nutritional stunting—linear growth failure due to inadequate calories that may be exacerbated by inflammation from ongoing infections. In areas with poor sanitation children experience vicious cycles of enteric infections and malnutrition, resulting in poor nutrient absorption from intestinal mucosa changes now termed “environmental enteropathy.” Emerging evidence links early childhood diarrhea and/or growth failure with increased CVD risk factors in later life, including dyslipidemia, hypertension and glucose intolerance. The mechanisms for these associations remain poorly understood and may relate to epigenetic responses to poor nutrition, increased inflammation or both. Given increases in CVD in developing areas of the world, associations between childhood malnutrition, early life infections and increased CVD risk factors underscore further reasons to improve nutrition and infection-related outcomes for young children worldwide. PMID:23110643
Escobar, Erik; Durgham, Ryan; Dammann, Olaf; Stopka, Thomas J
2015-01-01
Recently, the first comprehensive guidelines were published for pre-exposure prophylaxis (PrEP) for the prevention of HIV infection in populations with substantial risk of infection. Guidelines include a daily regimen of emtricitabine/tenofovir disoproxil fumarate (TDF/FTC) as well as condom usage during sexual activity. The relationship between the TDF/FTC intake regimen and condom usage is not yet fully understood. If men who have sex with men (MSM,) engage in high-risk sexual activities without using condoms when prescribed TDF/FTC they might be at an increased risk for other sexually transmitted diseases (STD). Our study focuses on the possible occurrence of behavioral changes among MSM in the United States over time with regard to condom usage. In particular, we were interested in creating a model of how increased uptake of TDF/FTC might cause a decline in condom usage, causing significant increases in non-HIV STD incidence, using gonococcal infection incidence as a biological endpoint. We used the agent-based modeling software NetLogo, building upon an existing model of HIV infection. We found no significant evidence for increased gonorrhea prevalence due to increased PrEP usage at any level of sample-wide usage, with a range of 0-90% PrEP usage. However, we did find significant evidence for decreased prevalence of HIV, with a maximal effect being reached when 5% to 10% of the MSM population used PrEP. Our findings appear to indicate that attitudes of aversion, within the medical community, toward the promotion of PrEP due to the potential risk of increased STD transmission are unfounded.
Prototypes Are Key Heuristic Information in Insight Problem Solving
ERIC Educational Resources Information Center
Yang, Wenjing; Dietrich, Arne; Liu, Peiduo; Ming, Dan; Jin, Yule; Nusbaum, Howard C.; Qiu, Jiang; Zhang, Qinglin
2016-01-01
Evidence from a range of fields indicates that inventions are often inspired by drawing a parallel to solutions found in nature. However, the cognitive mechanism of this process is not well understood. The cognitive mechanism of heuristic prototype in scientific innovation was tested with 3 experiments. First, 84 historical accounts of important…
A most dangerous game: death and injury to birds from porcupine quills
Todd Katzner; Tricia A. Miller; Jane Rodrigue; Steven Shaffer
2015-01-01
Predation is dangerous, not only for the prey but sometimes also for the predator. Because these dangers to predators are not well understood, we document evidence of predation or scavenging by a Golden Eagle (Aquila chrysaetos) on a North American porcupine (Erethizon dorsatum) in Pennsylvania, USA, with potentially lethal...
Environmentally Related Health Hazards in the Schools.
ERIC Educational Resources Information Center
Andrews, James B.; Neuroth, Richard
The quality of air inside the schoolhouses of America may have a profound effect on students' ability to concentrate on their lessons. The environmental hazards that influence the quality of the indoor air (IAQ) of our schools have not been well understood. Research evidence suggests that school age children and youth (especially those under the…
The Class I HDAC Inhibitor RGFP963 Enhances Consolidation of Cued Fear Extinction
ERIC Educational Resources Information Center
Bowers, Mallory E.; Xia, Bing; Carreiro, Samantha; Ressler, Kerry J.
2015-01-01
Evidence indicates that broad, nonspecific histone deacetylase (HDAC) inhibition enhances learning and memory, however, the contribution of the various HDACs to specific forms of learning is incompletely understood. Here, we show that the Class I HDAC inhibitor, RGFP963, enhances consolidation of cued fear extinction. However, RGFP966, a strong…
Insulin Receptor Signaling in Long-Term Memory Consolidation Following Spatial Learning
ERIC Educational Resources Information Center
Dou, Jing-Tao; Chen, Min; Dufour, Franck; Alkon, Daniel L.; Zhao, Wei-Qin
2005-01-01
Evidence has shown that the insulin and insulin receptor (IR) play a role in cognitive function. However, the detailed mechanisms underlying insulin's action on learning and memory are not yet understood. Here we investigated changes in long-term memory-associated expression of the IR and downstream molecules in the rat hippocampus. After…
Probing crystallinity of never-dried wood cellulose with Raman spectroscopy
Umesh P. Agarwal; Sally A. Ralph; Richard S. Reiner; Carlos Baez
2016-01-01
The structure of wood cell wall cellulose in its native state remains poorly understood, limiting the progress of research and development in numerous areas, including plant science, biofuels, and nanocellulose based materials. It is generally believed that cellulose in cell wall microfibrils has both crystalline and amorphous regions. However, there is evidence that...
Dentate Gyrus Is Necessary for Disambiguating Similar Object-Place Representations
ERIC Educational Resources Information Center
Lee, Inah; Solivan, Frances
2010-01-01
Objects are often remembered with their locations, which is an important aspect of event memory. Despite the well-known involvement of the hippocampus in event memory, detailed intrahippocampal mechanisms are poorly understood. In particular, no experimental evidence has been provided in support of the role of the dentate gyrus (DG) in…
Learner Agency: To Understand and to Be Understood
ERIC Educational Resources Information Center
Blair, Deborah V.
2009-01-01
What began as an exploration of student learning while listening to music evolved into a study of learner agency in a music classroom. Whilst students used and developed strategies that enabled their own success while listening to, performing and creating music, it became evident that they were proactively seeking musical understanding and growth…
Fostering School Belonging in Secondary Schools Using a Socio-Ecological Framework
ERIC Educational Resources Information Center
Allen, Kelly-Ann; Vella-Brodrick, Dianne; Waters, Lea
2016-01-01
The benefits of belonging and feeling connected to school for adolescent mental health and wellbeing are well documented, but how belonging is fostered is less understood. The present article puts forward a new conceptual framework of school belonging based on Bronfenbrenner's (1979) sociological model of human development, using evidence from a…
ERIC Educational Resources Information Center
Davis, Theresa M.
2013-01-01
Background: There is little evidence that technology acceptance is well understood in healthcare. The hospital environment is complex and dynamic creating a challenge when new technology is introduced because it impacts current processes and workflows which can significantly affect patient care delivery and outcomes. This study tested the effect…
NASA Technical Reports Server (NTRS)
Greenwood, R. C.; Franchi, I. A.; Zolensky, M. E.; Buchanan, P. C.
2016-01-01
The process responsible for the mass independent oxygen isotope variation observed in Solar System materials remains poorly understood. While self-shielding of CO, either in the early solar nebula, or precursor molecular cloud, appears to be a viable mechanism, alternative models have also been proposed.
Antecedent Frequency Effects on Anaphoric Pronoun Resolution: Evidence from Spanish
ERIC Educational Resources Information Center
Egusquiza, Nerea; Navarrete, Eduardo; Zawiszewski, Adam
2016-01-01
High-frequency words are usually understood and produced faster than low-frequency words. Although the effect of word frequency is a reliable phenomenon in many domains of language processing, it remains unclear whether and how frequency affects pronominal anaphoric resolution. We evaluated this issue by means of two self-paced reading…
USDA-ARS?s Scientific Manuscript database
Phosphorus (P) is often a limiting nutrient in freshwater ecosystems and excessive inputs can lead to eutrophication. In-stream cycling of P involves complex biological, chemical, and physical processes that are not fully understood. Microbial metabolisms are suspected to control oxygen-dependent up...
Abnormal Neural Sensitivity to Monetary Gains versus Losses among Adolescents at Risk for Depression
ERIC Educational Resources Information Center
Foti, Dan; Kotov, Roman; Klein, Daniel N.; Hajcak, Greg
2011-01-01
Major depressive disorder aggregates within families, although the mechanisms of transfer across generations are not well understood. In light of converging biological and behavioral evidence that depressive symptoms are associated with impaired reward processing, we examined whether adolescent girls with a parental history of depression would…
USDA-ARS?s Scientific Manuscript database
The mechanisms arthropods use to induce plant gall formation are poorly understood. However, there is growing evidence that effector proteins are involved. To examine this hypothesis, we sequenced the genome of the Hessian fly (Mayetiola destructor, M. des), an obligate plant parasitic gall midge an...
Superior Temporal Activation in Response to Dynamic Audio-Visual Emotional Cues
ERIC Educational Resources Information Center
Robins, Diana L.; Hunyadi, Elinora; Schultz, Robert T.
2009-01-01
Perception of emotion is critical for successful social interaction, yet the neural mechanisms underlying the perception of dynamic, audio-visual emotional cues are poorly understood. Evidence from language and sensory paradigms suggests that the superior temporal sulcus and gyrus (STS/STG) play a key role in the integration of auditory and visual…
USDA-ARS?s Scientific Manuscript database
Cucumber (Cucumis sativus L.) is an important vegetable crop worldwide, and fruit trichomes ir spines are an important trait for external fruit quality. The mechanisms underlying spine formation are not well understood, but there is evidence of the involvement of the plant-specific NAC family of tra...
Wallace, John L
2012-01-01
The mechanisms underlying the ability of nonsteroidal anti-inflammatory drugs (NSAIDs) to cause ulceration in the stomach and proximal duodenum are well understood, and this injury can largely be prevented through suppression of gastric acid secretion (mainly with proton pump inhibitors). In contrast, the pathogenesis of small intestinal injury induced by NSAIDs is less well understood, involving more complex mechanisms than those in the stomach and proximal duodenum. There is clear evidence for important contributions to NSAID enteropathy of enteric bacteria, bile and enterohepatic recirculation of the NSAID. There is no evidence that suppression of gastric acid secretion will reduce the incidence or severity of NSAID enteropathy. Indeed, clinical data suggest little, if any, benefit. Animal studies suggest a significant exacerbation of NSAID enteropathy when proton pump inhibitors are co-administered with the NSAID. This worsening of damage appears to be linked to changes in the number and types of bacteria in the small intestine during proton pump inhibitor therapy. The distinct mechanisms of NSAID-induced injury in the stomach/proximal duodenum versus the more distal small intestine likely dictate distinct strategies for prevention. PMID:21627632
How the embryonic brain tube twists
NASA Astrophysics Data System (ADS)
Chen, Zi; Guo, Qiaohang; Forsch, Nickolas; Taber, Larry
2014-03-01
During early development, the tubular brain of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This deformation is one of the major organ-level symmetry-breaking events in development. Available evidence suggests that bending is caused by differential growth, but the mechanism for torsion remains poorly understood. Since the heart almost always loops in the same direction that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is virtually nonexistent, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. In addition, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model is used to interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, reminiscent of D'Arcy Thompson's view of biological form as ``diagram of forces''.
The interplay between obesity and cancer: a fly view
2016-01-01
ABSTRACT Accumulating epidemiological evidence indicates a strong clinical association between obesity and an increased risk of cancer. The global pandemic of obesity indicates a public health trend towards a substantial increase in cancer incidence and mortality. However, the mechanisms that link obesity to cancer remain incompletely understood. The fruit fly Drosophila melanogaster has been increasingly used to model an expanding spectrum of human diseases. Fly models provide a genetically simpler system that is ideal for use as a first step towards dissecting disease interactions. Recently, the combining of fly models of diet-induced obesity with models of cancer has provided a novel model system in which to study the biological mechanisms that underlie the connections between obesity and cancer. In this Review, I summarize recent advances, made using Drosophila, in our understanding of the interplay between diet, obesity, insulin resistance and cancer. I also discuss how the biological mechanisms and therapeutic targets that have been identified in fly studies could be utilized to develop preventative interventions and treatment strategies for obesity-associated cancers. PMID:27604692
Chronic kidney disease, uremic milieu, and its effects on gut bacterial microbiota dysbiosis.
Chaves, Lee D; McSkimming, Daniel I; Bryniarski, Mark A; Honan, Amanda M; Abyad, Sham; Thomas, Shruthi A; Wells, Steven; Buck, Michael J; Sun, Yijun; Genco, Robert J; Quigg, Richard J; Yacoub, Rabi
2018-04-25
Several lines of evidence suggest that gut bacterial microbiota is altered in patients with chronic kidney disease (CKD), though the mechanism of which this dysbiosis takes place is not well understood. Recent studies delineated changes in gut microbiota in both CKD patients and experimental animal models using microarray chips. We present 16S ribosomal RNA gene sequencing of both stool pellets and small bowel contents of C57Bl/6J mice that underwent a remnant kidney model, and establish that changes in microbiota take place in the early gastrointestinal track. Increased intestinal urea concertation has been hypothesized as a leading contributor for dysbiotic changes in CKD. We show that urea transporters UT-A and UT-B mRNA are both expressed throughout the whole gastrointestinal track. The noted increase in intestinal urea concentration appears to be independent of urea transporters' expression. Urea supplementation in drinking water resulted in alteration in bacterial gut microbiota that is quite different than that seen in CKD. This indicates that increased intestinal urea concentration might not fully explain the CKD associated dysbiosis.
Obesity as a form of malnutrition: over-nutrition on the Uganda “malnutrition” agenda
Ngaruiya, Christine; Hayward, Alison; Post, Lori; Mowafi, Hani
2017-01-01
The objectives were to highlight the burden of overweight and obesity as an additional area of importance for the malnutrition agenda in Uganda and to provide evidence-based considerations for stakeholders involved. Introduction: Mirroring other Low- and Middle-Income Countries (LMICs), Uganda is experiencing a “double burden” of over-nutrition related issues - both obesity and overweight, and related non-communicable diseases (NCDs) alongside the under-nutrition that has long plagued the country. Despite the commonplace assumption that under-nutrition is the predominant form of malnutrition in Uganda, we explore recent literature that in fact, challenges this notion. While food insecurity has contributed to the under-nutrition problem, a lack of dietary diversity also has a demonstrated role in increasing over-nutrition. We cannot afford to ignore over-nutrition concomitant with stunting and wasting in the country. Increase in the burden of this less acknowledged form of malnutrition in Uganda is critical to investigate, and yet poorly understood. A move towards increased regionally targeted over-nutrition research, funding, government prioritization and advocacy is needed. PMID:29184601
Obesity as a form of malnutrition: over-nutrition on the Uganda "malnutrition" agenda.
Ngaruiya, Christine; Hayward, Alison; Post, Lori; Mowafi, Hani
2017-01-01
The objectives were to highlight the burden of overweight and obesity as an additional area of importance for the malnutrition agenda in Uganda and to provide evidence-based considerations for stakeholders involved. Mirroring other Low- and Middle-Income Countries (LMICs), Uganda is experiencing a "double burden" of over-nutrition related issues - both obesity and overweight, and related non-communicable diseases (NCDs) alongside the under-nutrition that has long plagued the country. Despite the commonplace assumption that under-nutrition is the predominant form of malnutrition in Uganda, we explore recent literature that in fact, challenges this notion. While food insecurity has contributed to the under-nutrition problem, a lack of dietary diversity also has a demonstrated role in increasing over-nutrition. We cannot afford to ignore over-nutrition concomitant with stunting and wasting in the country. Increase in the burden of this less acknowledged form of malnutrition in Uganda is critical to investigate, and yet poorly understood. A move towards increased regionally targeted over-nutrition research, funding, government prioritization and advocacy is needed.
Gobler, Christopher J; Doherty, Owen M; Hattenrath-Lehmann, Theresa K; Griffith, Andrew W; Kang, Yoonja; Litaker, R Wayne
2017-05-09
Global ocean temperatures are rising, yet the impacts of such changes on harmful algal blooms (HABs) are not fully understood. Here we used high-resolution sea-surface temperature records (1982 to 2016) and temperature-dependent growth rates of two algae that produce potent biotoxins, Alexandrium fundyense and Dinophysis acuminata , to evaluate recent changes in these HABs. For both species, potential mean annual growth rates and duration of bloom seasons significantly increased within many coastal Atlantic regions between 40°N and 60°N, where incidents of these HABs have emerged and expanded in recent decades. Widespread trends were less evident across the North Pacific, although regions were identified across the Salish Sea and along the Alaskan coastline where blooms have recently emerged, and there have been significant increases in the potential growth rates and duration of these HAB events. We conclude that increasing ocean temperature is an important factor facilitating the intensification of these, and likely other, HABs and thus contributes to an expanding human health threat.
Gobler, Christopher J.; Doherty, Owen M.; Hattenrath-Lehmann, Theresa K.; Griffith, Andrew W.; Kang, Yoonja; Litaker, R. Wayne
2017-01-01
Global ocean temperatures are rising, yet the impacts of such changes on harmful algal blooms (HABs) are not fully understood. Here we used high-resolution sea-surface temperature records (1982 to 2016) and temperature-dependent growth rates of two algae that produce potent biotoxins, Alexandrium fundyense and Dinophysis acuminata, to evaluate recent changes in these HABs. For both species, potential mean annual growth rates and duration of bloom seasons significantly increased within many coastal Atlantic regions between 40°N and 60°N, where incidents of these HABs have emerged and expanded in recent decades. Widespread trends were less evident across the North Pacific, although regions were identified across the Salish Sea and along the Alaskan coastline where blooms have recently emerged, and there have been significant increases in the potential growth rates and duration of these HAB events. We conclude that increasing ocean temperature is an important factor facilitating the intensification of these, and likely other, HABs and thus contributes to an expanding human health threat. PMID:28439007
Evidence for a direct effect of captopril on early steps of insulin action in BC3H-1 myocytes.
Moisés, Regina S; Carvalho, Carla R O; Shiota, Debora; Saad, Mario J A
2003-03-01
Captopril, an angiotensin-converting enzyme (ACE) inhibitor, has been reported to improve insulin sensitivity. However, despite extensive investigation, the mechanisms responsible for this effect are not fully understood. Reduction of plasma angiotensin II and inhibition of kininase II have been suggested to contribute to improve insulin sensitivity. Insulin binding was measured at tracer insulin concentration in intact cells with or without captopril treatment. Specific binding, expressed as percent of total insulin added, was not different in control and captopril-treated cells. However, captopril treatment caused an increase in insulin-induced insulin receptor substrate-1 (IRS-1) phosphorylation accompanied by an increased association of IRS-1 with phosphoinositide-3 kinase (PI-3 kinase), despite no change on insulin receptor (IR) autophosphorylation. There was also an increased threonine kinase B (AKT) phosphorylation in captopril-treated cells followed by enhanced basal and insulin-stimulated glucose uptake. These results indicate that captopril treatment has a direct effect on early phosphorylation events induced by insulin in BC3H-1 myocytes. Copyright 2003, Elsevier Science (USA). All rights reserved.
Similarity increases altruistic punishment in humans
Mussweiler, Thomas; Ockenfels, Axel
2013-01-01
Humans are attracted to similar others. As a consequence, social networks are homogeneous in sociodemographic, intrapersonal, and other characteristics—a principle called homophily. Despite abundant evidence showing the importance of interpersonal similarity and homophily for human relationships, their behavioral correlates and cognitive foundations are poorly understood. Here, we show that perceived similarity substantially increases altruistic punishment, a key mechanism underlying human cooperation. We induced (dis)similarity perception by manipulating basic cognitive mechanisms in an economic cooperation game that included a punishment phase. We found that similarity-focused participants were more willing to punish others’ uncooperative behavior. This influence of similarity is not explained by group identity, which has the opposite effect on altruistic punishment. Our findings demonstrate that pure similarity promotes reciprocity in ways known to encourage cooperation. At the same time, the increased willingness to punish norm violations among similarity-focused participants provides a rationale for why similar people are more likely to build stable social relationships. Finally, our findings show that altruistic punishment is differentially involved in encouraging cooperation under pure similarity vs. in-group conditions. PMID:24218611
Transient increases in methylbutenol emission following partial defoliation of Pinus ponderosa
NASA Astrophysics Data System (ADS)
Gray, Dennis W.
Methybutenol (MBO or 2-methyl-3-butene-2-ol) is a five-carbon alcohol produced and emitted in large amounts by many species of pine native to Western North America. Upon entering the atmosphere, MBO may engage in a series of chemical reactions which may ultimately lead to the production of tropospheric ozone which is a damaging pollutant. While the physical factors controlling MBO emission are well understood, the ecological factors controlling MBO emission have yet to be addressed. This study examines the response of MBO emission from Pinus ponderosa to herbivory simulated by needle clipping. Following defoliation early in the season, MBO emission from some plants tripled but similar increase did not occur later in the season. Anecdotal evidence suggests that the variable response of MBO emission to defoliation may have been due to the action of insect herbivores early in the season, or may have been due to phenological changes in the plants over the course of the season.
Arsenic and Immune Response to Infection During Pregnancy and Early Life
Attreed, Sarah E.; Navas-Acien, Ana
2017-01-01
Purpose of Review Arsenic, a known carcinogen and developmental toxicant, is a major threat to global health. While the contribution of arsenic exposure to chronic diseases and adverse pregnancy and birth outcomes is recognized, its ability to impair critical functions of humoral and cell-mediated immunity—including the specific mechanisms in humans—is not well understood. Arsenic has been shown to increase risk of infectious diseases that have significant health implications during pregnancy and early life. Here, we review the latest research on the mechanisms of arsenic-related immune response alterations that could underlie arsenic-associated increased risk of infection during the vulnerable periods of pregnancy and early life. Recent Findings The latest evidence points to alteration of antibody production and transplacental transfer as well as failure of T helper cells to produce IL-2 and proliferate. Summary Critical areas for future research include the effects of arsenic exposure during pregnancy and early life on immune responses to natural infection and the immunogenicity and efficacy of vaccines. PMID:28488132
Arsenic and Immune Response to Infection During Pregnancy and Early Life.
Attreed, Sarah E; Navas-Acien, Ana; Heaney, Christopher D
2017-06-01
Arsenic, a known carcinogen and developmental toxicant, is a major threat to global health. While the contribution of arsenic exposure to chronic diseases and adverse pregnancy and birth outcomes is recognized, its ability to impair critical functions of humoral and cell-mediated immunity-including the specific mechanisms in humans-is not well understood. Arsenic has been shown to increase risk of infectious diseases that have significant health implications during pregnancy and early life. Here, we review the latest research on the mechanisms of arsenic-related immune response alterations that could underlie arsenic-associated increased risk of infection during the vulnerable periods of pregnancy and early life. The latest evidence points to alteration of antibody production and transplacental transfer as well as failure of T helper cells to produce IL-2 and proliferate. Critical areas for future research include the effects of arsenic exposure during pregnancy and early life on immune responses to natural infection and the immunogenicity and efficacy of vaccines.
Irrmischer, Mona; van der Wal, C Natalie; Mansvelder, Huibert D; Linkenkaer-Hansen, Klaus
2018-01-01
There is growing evidence that the intermittent nature of mind wandering episodes and mood have a pronounced influence on trial-to-trial variability in performance. Nevertheless, the temporal dynamics and significance of such lapses in attention remains inadequately understood. Here, we hypothesize that the dynamics of fluctuations in sustained attention between external and internal sources of information obey so-called critical-state dynamics, characterized by trial-to-trial dependencies with long-range temporal correlations. To test this, we performed behavioral investigations measuring reaction times in a visual sustained attention task and cued introspection in probe-caught reports of mind wandering. We show that trial-to-trial variability in reaction times exhibit long-range temporal correlations in agreement with the criticality hypothesis. Interestingly, we observed the fastest responses in subjects with the weakest long-range temporal correlations and show the vital effect of mind wandering and bad mood on this response variability. The implications of these results stress the importance of future research to increase focus on behavioral variability.
Influence of ENSO on Gulf Stream cyclogenesis and the North Atlantic storm track
NASA Astrophysics Data System (ADS)
Li, C.; Schemm, S.; Ciasto, L.; Kvamsto, N. G.
2015-12-01
There is emerging evidence that climate in the North Atlantic-European sector is sensitive to vacillations of tropical Pacific sea surface temperatures, in particular, the central Pacific flavour of the El Nino Southern Oscillation (ENSO) and concomitant trends in atmospheric heating. The frequency of central Pacific ENSOs appears to have increased over the last decades and some studies suggest it may continue increasing in the future, but the precise mechanisms by which these events affect the North Atlantic synoptic scale circulation are poorly understood. Here, we show that central Pacific ENSOs influence where midlatitude cyclogenesis occurs over the Gulf Stream, producing more cyclogenesis in the jet exit region rather than in the climatologically preferred jet entrance region. The cyclones forming over the Gulf Stream in central Pacific ENSO seasons tend to veer north, penetrating deeper into the Arctic rather than into continental Europe. The shift in cyclogenesis is linked to changes in the large scale circulation, namely, the upper-level trough formed in the lee of the Rocky Mountains.
The response of thunderstorms and lightning to smoke from Amazonian fires
NASA Astrophysics Data System (ADS)
Altaratz, Orit; Koren, Ilan; Yair, Yoav; Price, Colin
2010-05-01
The effects of man-made aerosols on clouds are long believed to be a key component for model predictions of climate change, yet are one of the least understood. High aerosol concentrations can change the convection intensity and hence the electrical activity of thunderclouds. Focusing on the Amazon dry season in Brazil, where thousands of man-made forest fires inject smoke into the atmosphere, we studied the aerosol effects on thunderclouds and lightning. We used the ground-based World-Wide Lightning Location Network (WWLLN) measurements together with Aqua-MODIS remotely-sensed aerosol and cloud data to study the relationship between aerosol loading and lightning flash occurrence. We present evidence for the transition between two regimes, representing opposing effects of aerosols on clouds. The first is the microphysical effect which is manifested in an increase in convective intensity (and therefore in electrical activity), followed by the radiative effect that becomes dominant with the increase in aerosol loading leading to a decrease in convective intensity, manifested in lower lightning activity.
Throwing speed and accuracy in baseball and cricket players.
Freeston, Jonathan; Rooney, Kieron
2014-06-01
Throwing speed and accuracy are both critical to sports performance but cannot be optimized simultaneously. This speed-accuracy trade-off (SATO) is evident across a number of throwing groups but remains poorly understood. The goal was to describe the SATO in baseball and cricket players and determine the speed that optimizes accuracy. 20 grade-level baseball and cricket players performed 10 throws at 80% and 100% of maximal throwing speed (MTS) toward a cricket stump. Baseball players then performed a further 10 throws at 70%, 80%, 90%, and 100% of MTS toward a circular target. Baseball players threw faster with greater accuracy than cricket players at both speeds. Both groups demonstrated a significant SATO as vertical error increased with increases in speed; the trade-off was worse for cricketers than baseball players. Accuracy was optimized at 70% of MTS for baseballers. Throwing athletes should decrease speed when accuracy is critical. Cricket players could adopt baseball-training practices to improve throwing performance.
Sheth, Chandni; Furlong, Teri M; Keefe, Kristen A; Taha, Sharif A
2016-10-01
Ethanol has rewarding and aversive properties, and the balance of these properties influences voluntary ethanol consumption. Preclinical and clinical evidence show that the aversive properties of ethanol limit intake. The neural circuits underlying ethanol-induced aversion learning are not fully understood. We have previously shown that the lateral habenula (LHb), a region critical for aversive conditioning, plays an important role in ethanol-directed behaviors. However, the neurocircuitry through which LHb exerts its actions is unknown. In the present study, we investigate a role for the rostromedial tegmental nucleus (RMTg), a major LHb projection target, in regulating ethanol-directed behaviors. Rats received either sham or RMTg lesions and were studied during voluntary ethanol consumption; operant ethanol self-administration, extinction, and yohimbine-induced reinstatement of ethanol-seeking; and ethanol-induced conditioned taste aversion (CTA). RMTg lesions increased voluntary ethanol consumption and accelerated extinction of ethanol-induced CTA. The RMTg plays an important role in regulating voluntary ethanol consumption, possibly by mediating ethanol-induced aversive conditioning.
The development of hub architecture in the human functional brain network.
Hwang, Kai; Hallquist, Michael N; Luna, Beatriz
2013-10-01
Functional hubs are brain regions that play a crucial role in facilitating communication among parallel, distributed brain networks. The developmental emergence and stability of hubs, however, is not well understood. The current study used measures of network topology drawn from graph theory to investigate the development of functional hubs in 99 participants, 10-20 years of age. We found that hub architecture was evident in late childhood and was stable from adolescence to early adulthood. Connectivity between hub and non-hub ("spoke") regions, however, changed with development. From childhood to adolescence, the strength of connections between frontal hubs and cortical and subcortical spoke regions increased. From adolescence to adulthood, hub-spoke connections with frontal hubs were stable, whereas connectivity between cerebellar hubs and cortical spoke regions increased. Our findings suggest that a developmentally stable functional hub architecture provides the foundation of information flow in the brain, whereas connections between hubs and spokes continue to develop, possibly supporting mature cognitive function.
Mutations in Alström protein impair terminal differentiation of cardiomyocytes.
Shenje, Lincoln T; Andersen, Peter; Halushka, Marc K; Lui, Cecillia; Fernandez, Laviel; Collin, Gayle B; Amat-Alarcon, Nuria; Meschino, Wendy; Cutz, Ernest; Chang, Kenneth; Yonescu, Raluca; Batista, Denise A S; Chen, Yan; Chelko, Stephen; Crosson, Jane E; Scheel, Janet; Vricella, Luca; Craig, Brian D; Marosy, Beth A; Mohr, David W; Hetrick, Kurt N; Romm, Jane M; Scott, Alan F; Valle, David; Naggert, Jürgen K; Kwon, Chulan; Doheny, Kimberly F; Judge, Daniel P
2014-03-04
Cardiomyocyte cell division and replication in mammals proceed through embryonic development and abruptly decline soon after birth. The process governing cardiomyocyte cell cycle arrest is poorly understood. Here we carry out whole-exome sequencing in an infant with evidence of persistent postnatal cardiomyocyte replication to determine the genetic risk factors. We identify compound heterozygous ALMS1 mutations in the proband, and confirm their presence in her affected sibling, one copy inherited from each heterozygous parent. Next, we recognize homozygous or compound heterozygous truncating mutations in ALMS1 in four other children with high levels of postnatal cardiomyocyte proliferation. Alms1 mRNA knockdown increases multiple markers of proliferation in cardiomyocytes, the percentage of cardiomyocytes in G2/M phases, and the number of cardiomyocytes by 10% in cultured cells. Homozygous Alms1-mutant mice have increased cardiomyocyte proliferation at 2 weeks postnatal compared with wild-type littermates. We conclude that deficiency of Alström protein impairs postnatal cardiomyocyte cell cycle arrest.
Negative mood and mind wandering increase long-range temporal correlations in attention fluctuations
van der Wal, C. Natalie; Mansvelder, Huibert D.; Linkenkaer-Hansen, Klaus
2018-01-01
There is growing evidence that the intermittent nature of mind wandering episodes and mood have a pronounced influence on trial-to-trial variability in performance. Nevertheless, the temporal dynamics and significance of such lapses in attention remains inadequately understood. Here, we hypothesize that the dynamics of fluctuations in sustained attention between external and internal sources of information obey so-called critical-state dynamics, characterized by trial-to-trial dependencies with long-range temporal correlations. To test this, we performed behavioral investigations measuring reaction times in a visual sustained attention task and cued introspection in probe-caught reports of mind wandering. We show that trial-to-trial variability in reaction times exhibit long-range temporal correlations in agreement with the criticality hypothesis. Interestingly, we observed the fastest responses in subjects with the weakest long-range temporal correlations and show the vital effect of mind wandering and bad mood on this response variability. The implications of these results stress the importance of future research to increase focus on behavioral variability. PMID:29746529
Mutations in Alström Protein Impair Terminal Differentiation of Cardiomyocytes
Shenje, Lincoln T.; Andersen, Peter; Halushka, Marc K.; Lui, Cecillia; Fernandez, Laviel; Collin, Gayle B.; Amat-Alarcon, Nuria; Meschino, Wendy; Cutz, Ernest; Chang, Kenneth; Yonescu, Raluca; Batista, Denise A. S.; Chen, Yan; Chelko, Stephen; Crosson, Jane E.; Scheel, Janet; Vricella, Luca; Craig, Brian D.; Marosy, Beth A.; Mohr, David W.; Hetrick, Kurt N.; Romm, Jane M.; Scott, Alan F.; Valle, David; Naggert, Jürgen K.; Kwon, Chulan; Doheny, Kimberly F.; Judge, Daniel P.
2014-01-01
Cardiomyocyte cell division and replication in mammals proceed through embryonic development and abruptly decline soon after birth. The process governing cardiomyocyte cell cycle arrest is poorly understood. Here we carry out whole exome sequencing in an infant with evidence of persistent postnatal cardiomyocyte replication to determine the genetic risk factors. We identify compound heterozygous ALMS1 mutations in the proband, and confirm their presence in her affected sibling, one copy inherited from each heterozygous parent. Next, we recognise homozygous or compound heterozygous truncating mutations in ALMS1 in four other children with high levels of postnatal cardiomyocyte proliferation. Alms1 mRNA knockdown increases multiple markers of proliferation in cardiomyocytes, the percentage of cardiomyocytes in G2/M phases, and the number of cardiomyocytes by 10% in cultured cells. Homozygous Alms1-mutant mice have increased cardiomyocyte proliferation at two weeks postnatal compared to wild-type littermates. We conclude that deficiency of Alström protein impairs postnatal cardiomyocyte cell cycle arrest. PMID:24595103
The role of fructose in metabolism and cancer.
Charrez, Bérénice; Qiao, Liang; Hebbard, Lionel
2015-05-01
Fructose consumption has dramatically increased in the last 30 years. The principal form has been in the form of high-fructose corn syrup found in soft drinks and processed food. The effect of excessive fructose consumption on human health is only beginning to be understood. Fructose has been confirmed to induce several obesity-related complications associated with the metabolic syndrome. Here we present an overview of fructose metabolism and how it contrasts with that of glucose. In addition, we examine how excessive fructose consumption can affect de novo lipogenesis, insulin resistance, inflammation, and reactive oxygen species production. Fructose can also induce a change in the gut permeability and promote the release of inflammatory factors to the liver, which has potential implications in increasing hepatic inflammation. Moreover, fructose has been associated with colon, pancreas, and liver cancers, and we shall discuss the evidence for these observations. Taken together, data suggest that sustained fructose consumption should be curtailed as it is detrimental to long-term human health.
NASA Astrophysics Data System (ADS)
Maezumi, S. Y.; Power, M. J.; Mayle, F.; Iriarte, J. L.
2014-12-01
Mauritia flexuosa is one of the most widely distributed palms in the Neotropics. They are found in in warm, wet lowland environments ranging from dense tropical rainforests to monospecific communities restricted to flooded drainage basins. The monospecific stands of M. flexuosa communities provide structural complexity and habitat diversity for unique terrestrial and aquatic flora and fauna. These communities contribute to enhanced Neotropical diversity from both a taxonomic (α- diversity) and landscape (β-diversity) perspective. Conservation plans have begun to target M. flexuosa palm wetlands as potential refugia and their role in protection of watersheds. However, the long-term development and evolution of these systems is poorly understood. Numerous paleoecological studies from Amazonia suggest that the present day species distribution of M. flexuosa underwent a dramatic increase during the Late Holocene (after ca. 3000 cal yr. BP) that is often coupled with an increased in charcoal accumulation. Some researchers have interpreted these data as evidence for extensive human landscape modification. However, archaeological evidence supporting human landscape modification of M. flexuosa habitats is lacking. To investigate the long-term development of M. flexuosa, a 15,000-year high-resolution sedimentary record was analyzed for charcoal, phytolith and isotope data from Huanchaca Mesetta, Bolivia. To date, there is no evidence for human modification on the plateau, thus this records provides a control study to investigate the role of natural climate variability in the evolution of M. flexuosa communities. Increased insolation driven by Milankovitch precessional forcing resulted in an expansion of the South American Summer Monsoon, increased precipitation and a lengthening of the wet season, supporting the establishment of the modern palm swamp vegetation after 5,000 cal yr BP. Increased charcoal accumulation is likely associated with increased lightning ignitions that accompanied the expanded SASM. The paleofire and vegetation history from Huanchaca Mesetta provides conservationists, land-managers, and policy makers a context for understanding ecological response of M. flexuosa communities to increased warmth and drought stress expected for the 21st century.
Evidence based communication for health promotion: Indian lessons of last decade.
Suresh, K
2011-01-01
Good health promotion programs which help achieve public health goals are derived from using a mix of epidemiological and social and behavioral science research information. Social data informed by behavioral theories provides a lens of understanding how recommended behaviors are adopted by different individuals within the population over a period of time. In addition to social and epidemiological data, evidence based and scientifically planned and monitored strategic communication interventions have to be linked to available service components of the program. Communication is increasingly understood as an enabler of individual and social level change to achieve established developmental goals including health. Democratization movements and the advent of the internet have changed the environment around any program communication from top-down, expert-to-consumer (vertical) communication towards non-hierarchical, dialogue-based (horizontal) communication, through which the public increasingly questions recommendations of experts and public institutions on the basis of their own, often web based, research. The amount of information available has increased greatly, including scientifically valid data and evidence-based recommendations alongside poor quality data, personal opinions, and misinformation. Evidence-based approaches include engagement with and listening to stakeholders, and being transparent about decision making, and honest and open about uncertainty and risks. Decision and policy makers cannot assume what the public wants without undertaking social science and decision science research. The Global Polio Eradication Initiative and Integrated Disease Surveillance Projects (IDSP) in India haves shown that monitoring of public concerns needs to be continuous and responsive, and hand in hand with the monitoring of technical strategies and appropriate Information Technology support for, not only data transmission but also for videoconferencing and community involvement through toll free 24 × 7 call service with universal access. This article elucidates the vital role of Health Promotion, a research based communication process, in achieving developmental, particularly health goals. It underscores that communication is as much a science as an art, as much process as it is about outcomes. It advocates for increased linkages between epidemiological research and social science research in planning effective health promotion interventions with quality service delivery.
CpG island methylator phenotype (CIMP) in cancer: causes and implications.
Teodoridis, Jens M; Hardie, Catriona; Brown, Robert
2008-09-18
Strong evidence exists for a subgroup of tumours, from a variety of tissue types, exhibiting concordant tumour specific DNA methylation: the "CpG island methylator phenotype" (CIMP). Occurrence of CIMP is associated with a range of genetic and environmental factors, although the molecular causes are not well-understood. Both increased expression and aberrant targeting of DNA methyltransferases (DNMTs) could contribute to the occurrence of CIMP. One under-explored area is the possibility that DNA damage may induce or select for CIMP during carcinogenesis or treatment of tumours with chemotherapy. DNA damaging agents can induce DNA damage at guanine rich regions throughout the genome, including CpG islands. This DNA damage can result in stalled DNA synthesis, which will lead to localised increased DNMT1 concentration and therefore potentially increased DNA methylation at these sites. Chemotherapy can select for cells which have increased tolerance to DNA damage due to increased lesion bypass, in some cases by mechanisms which involve inactivation of genes by CpG island methylation. CIMP has been associated with worse patient prognosis, probably due to increased epigenetic plasticity. Therefore, further clinical testing of the diagnostic and prognostic value of the current CIMP markers, as well as increasing our understanding of the molecular causes underlying CIMP are required.
Madliger, Michael; Gasser, Christoph A; Schwarzenbach, René P; Sander, Michael
2011-05-15
Bt crops are genetically modified to be resistant against insect pests by expressing insecticidal Cry proteins. The processes governing the fate and bioavailability of the expressed transgenic Cry proteins in soils are poorly understood. We studied adsorption of Cry1Ab to negatively charged silica (SiO(2)) particles, a major soil constituent and a model for negatively charged mineral surfaces, at pH 5 to 10 and ionic strengths I = 10 mM to 250 mM, both in solution depletion and saturated column transport experiments. Cry1Ab-SiO(2) interactions were dominated by patch-controlled electrostatic attraction (PCEA), as evident from increasing Cry1Ab attraction to SiO(2) with decreasing I at pH at which both Cry1Ab and SiO(2) were net negatively charged. Experimental and modeling evidence is provided that the surface heterogeneity of SiO(2) particles modulated PCEA, leading to a fraction of adsorption sites with slow Cry1Ab desorption kinetics. Desorption rates from these sites increased upon increasing the solution pH. In toxicity bioassays, we demonstrated that Cry1Ab retained insecticidal activity when adsorbed to SiO(2), suggesting high protein conformational stability during adsorption-desorption cycles. Models predicting Cry1A protein adsorption in soils therefore need to account for combined effects of the nonuniform protein surface charge distribution and of sorbent surface heterogeneity.
Evidence-based surgery: knowledge, attitudes, and perceived barriers among surgical trainees.
Mittal, Rohin; Perakath, Benjamin
2010-01-01
This study was conducted to assess the knowledge and attitude of surgical trainees toward evidence-based medicine (EBM) and their perceived barriers to its practice. The McColl questionnaire and the BARRIERS scale were modified and incorporated into a single questionnaire, which was administered to all surgical trainees attending a Continuing Surgical Education meeting. Department of Surgery, Christian Medical College, Vellore, India. One hundred ten surgical trainees from 22 medical colleges. In all, 84.5% (93/110) trainees returned the questionnaire. The attitudes toward EBM were welcoming, although individual participants reported they welcomed EBM more than their colleagues did. Participants agreed that EBM was useful in everyday practice and that it improved patient care. About 50% of actual practice was considered evidence based. In all, 12.6% (10/89) of participants had received formal training in EBM, and 64.3% (54/84) of participants were aware of the Cochrane database of systemic reviews, but only 35.7% (30/84) read it regularly. Also, 67.8% (61/90) of respondents used protocols and guidelines developed by colleagues. However, 61.5% (56/91) of participants were interested in learning the skills of EBM. The terms absolute risk, relative risk, and clinical effectiveness were understood by >80% of respondents, whereas publication bias, confidence interval, and heterogeneity were poorly understood. The major barriers to practice of EBM were the inability to understand statistical analysis, inadequate facilities for implementation, lack of a single compiled source of literature, relevant literature not being readily available, and insufficient time on the job. Surgical trainees have a positive attitude towards EBM and have some familiarity with the common terms used in EBM. There is a need to increase awareness of, and provide access to, available sources of medical literature. Formal training in EBM, as well as basic statistical analysis, should form a part of the surgical curriculum to foster an environment favorable to the practice of EBM. Copyright © 2010 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Cruz-Muñoz, Mario E.; Fuentes-Pananá, Ezequiel M.
2018-01-01
Viruses are the most abundant and diverse biological entities in the planet. Historically, our main interest in viruses has focused on their pathogenic role, recognized by pandemics that have decimated the world population. However, viral infections have also played a major role in the evolution of cellular organisms, both through interchanging of genes with novel functions and shaping the immune system. Examples abound of infections that seriously compromise the host integrity, but evidence of plant and insect viruses mutualistic relationships have recently surfaced in which infected hosts are better suited for survival, arguing that virus-host interactions are initially parasitic but become mutualistic over years of co-evolution. A similar mutual help scenario has emerged with commensal gut bacteria. EBV is a herpesvirus that shares more than a hundred million years of co-evolution with humans, today successfully infecting close to 100% of the adult world population. Infection is usually acquired early in childhood persisting for the host lifetime mostly without apparent clinical symptoms. Disturbance of this homeostasis is rare and results in several diseases, of which the best understood are infectious mononucleosis and several EBV-associated cancers. Less understood are recently found inborn errors of the immune system that result in primary immunodeficiencies with an increased predisposition almost exclusive to EBV-associated diseases. Puzzling to these scenarios of broken homeostasis is the co-existence of immunosuppression, inflammation, autoimmunity and cancer. Homologous to EBV, HCMV, HHV-6 and HHV-7 are herpesviruses that also latently infect most individuals. Several lines of evidence support a mutualistic equilibrium between HCMV/EBV and hosts, that when altered trigger diseases in which the immune system plays a critical role. Interestingly, these beta and gamma herpesviruses persistently infect all immune lineages and early precursor cells. In this review, we will discuss the evidence of the benefits that infection of immune cells with these herpesviruses brings to the host. Also, the circumstances in which this positive relationship is broken, predisposing the host to diseases characterized by an abnormal function of the host immune system. PMID:29354096
A Systematic Review of Vocational Interventions for Young Adults With Autism Spectrum Disorders
McPheeters, Melissa L.; Sathe, Nila A.; Dove, Dwayne; Veenstra-VanderWeele, Jeremy; Warren, Zachary
2012-01-01
BACKGROUND AND OBJECTIVE: Many individuals with autism spectrum disorders (ASDs) are approaching adolescence and young adulthood; interventions to assist these individuals with vocational skills are not well understood. This study systematically reviewed evidence regarding vocational interventions for individuals with ASD between the ages of 13 and 30 years. METHODS: The Medline, PsycINFO, and ERIC databases (1980–December 2011) and reference lists of included articles were searched. Two reviewers independently assessed each study against predetermined inclusion/exclusion criteria. Two reviewers independently extracted data regarding participant and intervention characteristics, assessment techniques, and outcomes, and assigned overall quality and strength of evidence ratings based on predetermined criteria. RESULTS: Five studies were identified; all were of poor quality and all focused on on-the-job supports as the employment/vocational intervention. Short-term studies reported that supported employment was associated with improvements in quality of life (1 study), ASD symptoms (1 study), and cognitive functioning (1 study). Three studies reported that interventions increased rates of employment for young adults with ASD. CONCLUSIONS: Few studies have been conducted to assess vocational interventions for adolescents and young adults with ASD. As such, there is very little evidence available for specific vocational treatment approaches as individuals transition to adulthood. All studies of vocational approaches were of poor quality, which may reflect the recent emergence of this area of research. Individual studies suggest that vocational programs may increase employment success for some; however, our ability to understand the overall benefit of supported employment programs is limited given the existing research. PMID:22926170
Cawley, Elizabeth I.; Park, Sarah; Rot, Marije aan het; Sancton, Kimberley; Benkelfat, Chawki; Young, Simon N.; Boivin, Diane B.; Leyton, Marco
2013-01-01
Background Despite evidence that bright light can improve mood, the neurobiology remains poorly understood. Some evidence implicates the catecholamines. In the present study, we measured the effects of transiently decreasing dopamine (DA) synthesis on mood and motivational states in healthy women with mild seasonal mood changes who were tested in either bright or dim light. Methods On 2 test days, participants slept overnight in a light-controlled room. On the morning of each session, half of the participants awoke to gradual increases of bright light, up to 3000 lux, and half to dim light (10 lux). For all participants, DA was reduced on 1 of the test days using the acute phenylalanine/tyrosine depletion (APTD) method; on the other day, they ingested a nutritionally balanced control mixture (BAL). Beginning 4 hours postingestion, participants completed subjective mood questionnaires, psychological tests and a progressive ratio breakpoint task during which they worked for successive units of $5. Results Thirty-two women participated in our study. The APTD lowered mood, agreeableness, energy and the willingness to work for monetary reward. The effects on energy and motivation were independent of light, while the effects on mood and agreeableness were seen in the dim condition only, being prevented by bright light. Limitations Acute phenylalanine/tyrosine depletion might affect systems other than DA. The sample size was small. Conclusion These results suggest that increased DA function may be responsible for some of the beneficial effects of light, while adding to the evidence that the neurobiology of mood and motivational states can be dissociated. PMID:23735584
Explaining risk for suicidal ideation in adolescent offspring of mothers with depression.
Hammerton, G; Zammit, S; Thapar, A; Collishaw, S
2016-01-01
It is well-established that offspring of depressed mothers are at increased risk for suicidal ideation. However, pathways involved in the transmission of risk for suicidal ideation from depressed mothers to offspring are poorly understood. The aim of this study was to examine the contribution of potential mediators of this association, including maternal suicide attempt, offspring psychiatric disorder and the parent-child relationship. Data were utilized from a population-based birth cohort (ALSPAC). Three distinct classes of maternal depression symptoms across the first 11 years of the child's life had already been identified (minimal, moderate, chronic-severe). Offspring suicidal ideation was assessed at age 16 years. Data were analysed using structural equation modelling. There was evidence for increased risk of suicidal ideation in offspring of mothers with chronic-severe depression symptoms compared to offspring of mothers with minimal symptoms (odds ratio 3.04, 95% confidence interval 2.19-4.21). The majority of this association was explained through maternal suicide attempt and offspring psychiatric disorder. There was also evidence for an independent indirect effect via the parent-child relationship in middle childhood. There was no longer evidence of a direct effect of maternal depression on offspring suicidal ideation after accounting for all three mediators. The pattern of results was similar when examining mechanisms for maternal moderate depression symptoms. Findings highlight that suicide prevention efforts in offspring of depressed mothers should be particularly targeted at both offspring with a psychiatric disorder and offspring whose mothers have made a suicide attempt. Interventions aimed at improving the parent-child relationship may also be beneficial.
The role of the commensal microbiota in adaptive and maladaptive stressor-induced immunomodulation
Mackos, Amy R.; Maltz, Ross; Bailey, Michael T.
2016-01-01
Over the past decade, it has become increasingly evident that there are extensive bidirectional interactions between the body and its microbiota. These interactions are evident during stressful periods, where it is recognized that commensal microbiota community structure is significantly changed. Many different stressors, ranging from early life stressors to stressors administered during adulthood, lead to significant, community-wide differences in the microbiota. The mechanisms through which this occurs are not yet known, but it is known that commensal microbes can recognize, and respond to, mammalian hormones and neurotransmitters, including those that are involved with the physiological response to stressful stimuli. In addition, the physiological stress response also changes many aspects of gastrointestinal physiology that can impact microbial community composition. Thus, there are many routes through which microbial community composition might be disrupted during stressful periods. The implications of these disruptions in commensal microbial communities for host health are still not well understood, but the commensal microbiota have been linked to stressor-induced immunopotentiation. The role of the microbiota in stressor-induced immunopotentiation can be adaptive, such as when these microbes stimulate innate defenses against bacterial infection. However, the commensal microbiota can also lead to maladaptive immune responses during stressor-exposure. This is evident in animal models of colonic inflammation where stressor exposure increases the inflammation through mechanisms involving the microbiota. It is likely that during stressor exposure, immune cell functioning is regulated by combined effects of both neurotransmitters/hormones and commensal microbes. Defining this regulation should be a focus of future studies. PMID:27760302
Beaulieu, Kristine; Hopkins, Mark; Blundell, John; Finlayson, Graham
2017-12-28
The current obesogenic environment promotes physical inactivity and food consumption in excess of energy requirements, two important modifiable risk factors influencing energy balance. Habitual physical activity has been shown to impact not only energy expenditure, but also energy intake through mechanisms of appetite control. This review summarizes recent theory and evidence underpinning the role of physical activity in the homeostatic and non-homeostatic mechanisms controlling appetite. Energy intake along the spectrum of physical activity levels (inactive to highly active) appears to be J-shaped, with low levels of physical activity leading to dysregulated appetite and a mismatch between energy intake and expenditure. At higher levels, habitual physical activity influences homeostatic appetite control in a dual-process action by increasing the drive to eat through greater energy expenditure, but also by enhancing post-meal satiety, allowing energy intake to better match energy expenditure in response to hunger and satiety signals. There is clear presumptive evidence that physical activity energy expenditure can act as a drive (determinant) of energy intake. The influence of physical activity level on non-homeostatic appetite control is less clear, but low levels of physical activity may amplify hedonic states and behavioural traits favouring overconsumption indirectly through increased body fat. More evidence is required to understand the interaction between physical activity, appetite control and diet composition on passive overconsumption and energy balance. Furthermore, potential moderators of appetite control along the spectrum of physical activity, such as body composition, sex, and type, intensity and timing of physical activity, remain to be fully understood. Copyright © 2018 Elsevier Inc. All rights reserved.
Cawley, Elizabeth I; Park, Sarah; aan het Rot, Marije; Sancton, Kimberley; Benkelfat, Chawki; Young, Simon N; Boivin, Diane B; Leyton, Marco
2013-11-01
Despite evidence that bright light can improve mood, the neurobiology remains poorly understood. Some evidence implicates the catecholamines. In the present study, we measured the effects of transiently decreasing dopamine (DA) synthesis on mood and motivational states in healthy women with mild seasonal mood changes who were tested in either bright or dim light. On 2 test days, participants slept overnight in a light-controlled room. On the morning of each session, half of the participants awoke to gradual increases of bright light, up to 3000 lux, and half to dim light (10 lux). For all participants, DA was reduced on 1 of the test days using the acute phenylalanine/tyrosine depletion (APTD) method; on the other day, they ingested a nutritionally balanced control mixture (BAL). Beginning 4 hours postingestion, participants completed subjective mood questionnaires, psychological tests and a progressive ratio breakpoint task during which they worked for successive units of $5. Thirty-two women participated in our study. The APTD lowered mood, agreeableness, energy and the willingness to work for monetary reward. The effects on energy and motivation were independent of light, while the effects on mood and agreeableness were seen in the dim condition only, being prevented by bright light. Acute phenylalanine/tyrosine depletion might affect systems other than DA. The sample size was small. These results suggest that increased DA function may be responsible for some of the beneficial effects of light, while adding to the evidence that the neurobiology of mood and motivational states can be dissociated.
The role of the commensal microbiota in adaptive and maladaptive stressor-induced immunomodulation.
Mackos, Amy R; Maltz, Ross; Bailey, Michael T
2017-02-01
Over the past decade, it has become increasingly evident that there are extensive bidirectional interactions between the body and its microbiota. These interactions are evident during stressful periods, where it is recognized that commensal microbiota community structure is significantly changed. Many different stressors, ranging from early life stressors to stressors administered during adulthood, lead to significant, community-wide differences in the microbiota. The mechanisms through which this occurs are not yet known, but it is known that commensal microbes can recognize, and respond to, mammalian hormones and neurotransmitters, including those that are involved with the physiological response to stressful stimuli. In addition, the physiological stress response also changes many aspects of gastrointestinal physiology that can impact microbial community composition. Thus, there are many routes through which microbial community composition might be disrupted during stressful periods. The implications of these disruptions in commensal microbial communities for host health are still not well understood, but the commensal microbiota have been linked to stressor-induced immunopotentiation. The role of the microbiota in stressor-induced immunopotentiation can be adaptive, such as when these microbes stimulate innate defenses against bacterial infection. However, the commensal microbiota can also lead to maladaptive immune responses during stressor-exposure. This is evident in animal models of colonic inflammation where stressor exposure increases the inflammation through mechanisms involving the microbiota. It is likely that during stressor exposure, immune cell functioning is regulated by combined effects of both neurotransmitters/hormones and commensal microbes. Defining this regulation should be a focus of future studies. Copyright © 2016 Elsevier Inc. All rights reserved.
New Evidence on What Works in Effective Public Reporting.
Sandmeyer, Brent; Fraser, Irene
2016-06-01
To describe the current state of the public reporting field and provide guidance to public report producers based on the evidence. Public reports should address the questions and priorities that consumers actually have; present information credibly and in a way that is understood by the intended audience; reach the intended audience; and enable consumers to act on the information. Public reports have advanced greatly in recent years, but there remains much room for improvement. Report producers should continually evaluate their reports and apply the latest evidence to maximize their usefulness and impact. © Published 2016. This article is a U.S. Government work and is in the public domain in the USA.
NASA Astrophysics Data System (ADS)
Irvine, P. J.; Keith, D.; Dykema, J. A.; Vecchi, G. A.; Horowitz, L. W.
2016-12-01
Solar geoengineering may limit or even halt the rise in global-average surface temperatures. Evidence from the geoMIP model intercomparison project shows that idealized geoengineering can greatly reduce temperature changes on a region-by-region basis. If solar geoengineering is used to hold radiative forcing or surface temperatures constant in the face of rising CO2, then the global evaporation and precipitation rates will be reduced below pre-industrial. The spartial and frequency distribution of the precipitation response is, however, much less well understood. There is limited evidence that solar geoengineering may reduce extreme precipitation events more that it reduces mean precipitation, but that evidence is based on relatively course resolution models that may to a poor job representing the distribution of extreme precipitation in the current climate. The response of global and regional climate, as well as tropical cyclone (TC) activity, to increasing solar geoengineering is explored through experiments with climate models spanning a broad range of atmospheric resolutions. Solar geoengineering is represented by an idealized adjustment of the solar constant that roughly halves the rate of increase in radiative forcing in a scenario with increasing CO2 concentration. The coarsest resolution model has approximately a 2-degree global resolution, representative of the typical resolution of past GCMs used to explore global response to CO2 increase, and its response is compared to that of two tropical cyclone permitting GCMs of approximately 0.5 and 0.25 degree resolution (FLOR and HiFLOR). The models have exactly the same ocean and sea-ice components, as well as the same parameterizations and parameter settings. These high-resolution models are used for real-time seasonal prediction, providing a unified framework for seasonal-to-multidecadal climate modeling. We assess the extreme precipitation response, comparing the frequency distribution of extreme events with and without solar geoengineering. We compare our results to two prior studies of the response of climate extremes to solar geoengineering.
Torres, Iviana M; Demirdjian, Sally; Vargas, Jennifer; Goodale, Britton C; Berwin, Brent
2017-07-01
Bacterial infection can lead to acidosis of the local microenvironment, which is believed to exacerbate disease pathogenesis; however, the mechanisms by which changes in pH alter disease progression are poorly understood. We test the hypothesis that acidosis enhances respiratory epithelial cell death in response to infection with Pseudomonas aeruginosa Our findings support the idea that acidosis in the context of P. aeruginosa infection results in increased epithelial cell cytotoxicity due to ExoU intoxication. Importantly, enforced maintenance of neutral pH during P. aeruginosa infection demonstrates that cytotoxicity is dependent on the acidosis. Investigation of the underlying mechanisms revealed that host cell cytotoxicity correlated with increased bacterial survival during an acidic infection that was due to reduced bactericidal activity of host-derived antimicrobial peptides. These findings extend previous reports that the activities of antimicrobial peptides are pH-dependent and provide novel insights into the consequences of acidosis on infection-derived pathology. Therefore, this report provides the first evidence that physiological levels of acidosis increase the susceptibility of epithelial cells to acute Pseudomonas infection and demonstrates the benefit of maintaining pH homeostasis during a bacterial infection. Copyright © 2017 the American Physiological Society.
Involvement of PUMA in pericyte migration induced by methamphetamine.
Zhang, Yanhong; Zhang, Yuan; Bai, Ying; Chao, Jie; Hu, Gang; Chen, Xufeng; Yao, Honghong
2017-07-01
Mounting evidence indicates that methamphetamine causes blood-brain barrier damage, with emphasis on endothelial cells. The role of pericytes in methamphetamine-induced BBB damage remains unknown. Our study demonstrated that methamphetamine increased the migration of pericytes from the endothelial basement membrane. However, the detailed mechanisms underlying this process remain poorly understood. Thus, we examined the molecular mechanisms involved in methamphetamine-induced pericyte migration. The results showed that exposure of C3H/10T1/2 cells and HBVPs to methamphetamine increased PUMA expression via activation of the sigma-1 receptor, MAPK and Akt/PI3K pathways. Moreover, methamphetamine treatment resulted in the increased migration of C3H/10T1/2 cells and HBVPs. Knockdown of PUMA in pericytes transduced with PUMA siRNA attenuated the methamphetamine-induced increase in cell migration through attenuation of integrin and tyrosine kinase mechanisms, implicating a role of PUMA in the migration of C3H/10T1/2 cells and HBVPs. This study has demonstrated that methamphetamine-mediated pericytes migration involves PUMA up-regulation. Thus, targeted studies of PUMA could provide insights to facilitate the development of a potential therapeutic approach for alleviation of methamphetamine-induced pericyte migration. Copyright © 2017. Published by Elsevier Inc.
Lee, M H; Chung, S W; Kang, B Y; Kim, K-M; Kim, T S
2002-01-01
Exposure to cigarette smoke is known to increase the risk of the development of allergic disease. The mechanism is not well understood. In this study, we determined the effect of hydroquinone (HQ), a major metabolite of benzene present in large quantities in cigarette tar, on interleukin-4 (IL-4) production by CD4+ T cells. HQ significantly enhanced IL-4 production by keyhole limpet haemocyanin (KLH)-primed CD4+ T cells in a dose-dependent manner. The enhancing effect of HQ on IL-4 production was maximal at a concentration of 50 µm. It increased the level of IL-4 production approximately 10-fold. HQ enhanced IL-4 mRNA expression and also IL-4 gene promoter activity, suggesting that the enhancing effect of HQ on IL-4 production may occur at the transcriptional level. Furthermore, the injection of KLH-primed mice with HQ resulted in a significant increase in the levels of IL-4 and immunoglobulin E. These findings provide evidence that HQ, a major component of cigarette tar, may enhance allergic immune responses by inducing the production of IL-4 in CD4+ T cells. PMID:12153512
Walls, Helen; Liverani, Marco; Chheng, Kannarath; Parkhurst, Justin
2017-11-10
Discussions within the health community routinely emphasise the importance of evidence in informing policy formulation and implementation. Much of the support for the evidence-based policy movement draws from concern that policy decisions are often based on inadequate engagement with high-quality evidence. In many such discussions, evidence is treated as differing only in quality, and assumed to improve decisions if it can only be used more. In contrast, political science scholars have described this as an overly simplistic view of the policy-making process, noting that research 'use' can mean a variety of things and relies on nuanced aspects of political systems. An approach more in recognition of how policy-making systems operate in practice can be to consider how institutions and ideas influence which pieces of evidence appear to be relevant for, and are used within, different policy processes. Drawing on in-depth interviews undertaken in 2015-2016 with key health sector stakeholders in Cambodia, we investigate the evidence perceived to be relevant to policy decisions for three contrasting health policy examples, namely tobacco control, HIV/AIDS and performance-based salary incentives. These cases allow us to examine the ways that policy-relevant evidence may differ given the framing of the issue and the broader institutional context in which evidence is considered. The three health issues show few similarities in how pieces of evidence were used in various aspects of policy-making, despite all being discussed within a broad policy environment in which evidence-based policy-making is rhetorically championed. Instead, we find that evidence use can be better understood by mapping how these health policy issues differ in terms of the issue characteristics, and also in terms of the stakeholders structurally established as having a dominant influence for each issue. Both of these have important implications for evidence use. Contrasting concerns of key stakeholders meant that evidence related to differing issues could be understood in terms of how it was relevant to policy. The stakeholders involved, however, could further be seen to possess differing logics about how to go about achieving their various outcomes - logics that could further help explain the differences seen in evidence utilisation. A comparative approach reiterates that evidence is not a uniform concept for which more is obviously better, but rather illustrates how different constructions and pieces of evidence become relevant in relation to the features of specific health policy decisions. An institutional approach that considers the structural position of stakeholders with differing core goals or objectives, as well as their logics related to evidence utilisation, can further help to understand some of the complexities of evidence use in health policy-making.
Evidence integration in model-based tree search
Solway, Alec; Botvinick, Matthew M.
2015-01-01
Research on the dynamics of reward-based, goal-directed decision making has largely focused on simple choice, where participants decide among a set of unitary, mutually exclusive options. Recent work suggests that the deliberation process underlying simple choice can be understood in terms of evidence integration: Noisy evidence in favor of each option accrues over time, until the evidence in favor of one option is significantly greater than the rest. However, real-life decisions often involve not one, but several steps of action, requiring a consideration of cumulative rewards and a sensitivity to recursive decision structure. We present results from two experiments that leveraged techniques previously applied to simple choice to shed light on the deliberation process underlying multistep choice. We interpret the results from these experiments in terms of a new computational model, which extends the evidence accumulation perspective to multiple steps of action. PMID:26324932
Zhang, Yuhua; Wang, Yongfan; Yu, Shixiao
2014-01-01
Because the frequency of heterospecific interactions inevitably increases with species richness in a community, biodiversity effects must be expressed by such interactions. However, little is understood how heterospecific interactions affect ecosystem productivity because rarely are biodiversity ecosystem functioning experiments spatially explicitly manipulated. To test the effect of heterospecific interactions on productivity, direct evidence of heterospecific neighborhood interaction is needed. In this study we conducted experiments with a detailed spatial design to investigate whether and how heterospecific neighborhood interactions promote primary productivity in a grassland community. The results showed that increasing the heterospecific: conspecific contact ratio significantly increased productivity. We found there was a significant difference in the variation in plant height between monoculture and mixture communities, suggesting that height-asymmetric competition for light plays a central role in promoting productivity. Heterospecific interactions make tall plants grow taller and short plants become smaller in mixtures compared to monocultures, thereby increasing the efficiency of light interception and utilization. Overyielding in the mixture communities arises from the fact that the loss in the growth of short plants is compensated by the increased growth of tall plants. The positive correlation between species richness and primary production was strengthened by increasing the frequency of heterospecific interactions. We conclude that species richness significantly promotes primary ecosystem production through heterospecific neighborhood interactions. PMID:25350670
Zhang, Yuhua; Wang, Yongfan; Yu, Shixiao
2014-01-01
Because the frequency of heterospecific interactions inevitably increases with species richness in a community, biodiversity effects must be expressed by such interactions. However, little is understood how heterospecific interactions affect ecosystem productivity because rarely are biodiversity ecosystem functioning experiments spatially explicitly manipulated. To test the effect of heterospecific interactions on productivity, direct evidence of heterospecific neighborhood interaction is needed. In this study we conducted experiments with a detailed spatial design to investigate whether and how heterospecific neighborhood interactions promote primary productivity in a grassland community. The results showed that increasing the heterospecific: conspecific contact ratio significantly increased productivity. We found there was a significant difference in the variation in plant height between monoculture and mixture communities, suggesting that height-asymmetric competition for light plays a central role in promoting productivity. Heterospecific interactions make tall plants grow taller and short plants become smaller in mixtures compared to monocultures, thereby increasing the efficiency of light interception and utilization. Overyielding in the mixture communities arises from the fact that the loss in the growth of short plants is compensated by the increased growth of tall plants. The positive correlation between species richness and primary production was strengthened by increasing the frequency of heterospecific interactions. We conclude that species richness significantly promotes primary ecosystem production through heterospecific neighborhood interactions.
Conflicting health information: a critical research need.
Carpenter, Delesha M; Geryk, Lorie L; Chen, Annie T; Nagler, Rebekah H; Dieckmann, Nathan F; Han, Paul K J
2016-12-01
Conflicting health information is increasing in amount and visibility, as evidenced most recently by the controversy surrounding the risks and benefits of childhood vaccinations. The mechanisms through which conflicting information affects individuals are poorly understood; thus, we are unprepared to help people process conflicting information when making important health decisions. In this viewpoint article, we describe this problem, summarize insights from the existing literature on the prevalence and effects of conflicting health information, and identify important knowledge gaps. We propose a working definition of conflicting health information and describe a conceptual typology to guide future research in this area. The typology classifies conflicting information according to four fundamental dimensions: the substantive issue under conflict, the number of conflicting sources (multiplicity), the degree of evidence heterogeneity and the degree of temporal inconsistency. © 2015 The Authors. Health Expectations Published by John Wiley & Sons Ltd.
Cold-sensing regulates Drosophila growth through insulin-producing cells
Li, Qiaoran; Gong, Zhefeng
2015-01-01
Across phyla, body size is linked to climate. For example, rearing fruit flies at lower temperatures results in bigger body sizes than those observed at higher temperatures. The underlying molecular basis of this effect is poorly understood. Here we provide evidence that the temperature-dependent regulation of Drosophila body size depends on a group of cold-sensing neurons and insulin-producing cells (IPCs). Electrically silencing IPCs completely abolishes the body size increase induced by cold temperature. IPCs are directly innervated by cold-sensing neurons. Stimulation of these cold-sensing neurons activates IPCs, promotes synthesis and secretion of Drosophila insulin-like peptides and induces a larger body size, mimicking the effects of rearing the flies in cold temperature. Taken together, these findings reveal a neuronal circuit that mediates the effects of low temperature on fly growth. PMID:26648410
Cancer Patient Navigator Tasks across the Cancer Care Continuum
Braun, Kathryn L.; Kagawa-Singer, Marjorie; Holden, Alan E. C.; Burhansstipanov, Linda; Tran, Jacqueline H.; Seals, Brenda F.; Corbie-Smith, Giselle; Tsark, JoAnn U.; Harjo, Lisa; Foo, Mary Anne; Ramirez, Amelie G.
2011-01-01
Cancer patient navigation (PN) programs have been shown to increase access to and utilization of cancer care for poor and underserved individuals. Despite mounting evidence of its value, cancer patient navigation is not universally understood or provided. We describe five PN programs and the range of tasks their navigators provide across the cancer care continuum (education and outreach, screening, diagnosis and staging, treatment, survivorship, and end-of-life). Tasks are organized by their potential to make cancer services understandable, available, accessible, affordable, appropriate, and accountable. Although navigators perform similar tasks across the five programs, their specific approaches reflect differences in community culture, context, program setting, and funding. Task lists can inform the development of programs, job descriptions, training, and evaluation. They also may be useful in the move to certify navigators and establish mechanisms for reimbursement for navigation services. PMID:22423178
Visualizing uncertainty about the future.
Spiegelhalter, David; Pearson, Mike; Short, Ian
2011-09-09
We are all faced with uncertainty about the future, but we can get the measure of some uncertainties in terms of probabilities. Probabilities are notoriously difficult to communicate effectively to lay audiences, and in this review we examine current practice for communicating uncertainties visually, using examples drawn from sport, weather, climate, health, economics, and politics. Despite the burgeoning interest in infographics, there is limited experimental evidence on how different types of visualizations are processed and understood, although the effectiveness of some graphics clearly depends on the relative numeracy of an audience. Fortunately, it is increasingly easy to present data in the form of interactive visualizations and in multiple types of representation that can be adjusted to user needs and capabilities. Nonetheless, communicating deeper uncertainties resulting from incomplete or disputed knowledge--or from essential indeterminacy about the future--remains a challenge.
Social influences on neuroplasticity: Stress and interventions to promote well-being
Davidson, Richard J.; McEwen, Bruce S.
2012-01-01
Experiential factors shape the neural circuits underlying social and emotional behavior from the prenatal period to the end of life. These factors include both incidental influences such as early adversity as well as intentional influences that can be produced in humans through specific interventions designed to promote prosocial behavior and well-being. Key extant evidence in animal models and humans is reviewed. While the precise mechanisms of plasticity are still not fully understood, moderate to severe stress appears to increase growth of several sectors of the amygdala while effects in the hippocampus and prefrontal cortex tend to be opposite. Structural and functional changes in the brain have been observed with cognitive therapy and certain forms of meditation and lead to the suggestion that well-being and other prosocial characteristics might be enhanced through training. PMID:22534579
Grant, Aileen; Sullivan, Frank; Dowell, Jon
2013-06-21
Prescribing is a core activity for general practitioners, yet significant variation in the quality of prescribing has been reported. This suggests there may be room for improvement in the application of the current best research evidence. There has been substantial investment in technologies and interventions to address this issue, but effect sizes so far have been small to moderate. This suggests that prescribing is a decision-making process that is not sufficiently understood. By understanding more about prescribing processes and the implementation of research evidence, variation may more easily be understood and more effective interventions proposed. An ethnographic study in three Scottish general practices with diverse organizational characteristics. Practices were ranked by their performance against Audit Scotland prescribing quality indicators, incorporating established best research evidence. Two practices of high prescribing quality and one practice of low prescribing quality were recruited. Participant observation, formal and informal interviews, and a review of practice documentation were employed. Practices ranked as high prescribing quality consistently made and applied macro and micro prescribing decisions, whereas the low-ranking practice only made micro prescribing decisions. Macro prescribing decisions were collective, policy decisions made considering research evidence in light of the average patient, one disease, condition, or drug. Micro prescribing decisions were made in consultation with the patient considering their views, preferences, circumstances and other conditions (if necessary).Although micro prescribing can operate independently, the implementation of evidence-based, quality prescribing was attributable to an interdependent relationship. Macro prescribing policy enabled prescribing decisions to be based on scientific evidence and applied consistently where possible. Ultimately, this influenced prescribing decisions that occur at the micro level in consultation with patients. General practitioners in the higher prescribing quality practices made two different 'types' of prescribing decision; macro and micro. Macro prescribing informs micro prescribing and without a macro basis to draw upon the low-ranked practice had no effective mechanism to engage with, reflect on and implement relevant evidence. Practices that recognize these two levels of decision making about prescribing are more likely to be able to implement higher quality evidence.
2013-01-01
Background Prescribing is a core activity for general practitioners, yet significant variation in the quality of prescribing has been reported. This suggests there may be room for improvement in the application of the current best research evidence. There has been substantial investment in technologies and interventions to address this issue, but effect sizes so far have been small to moderate. This suggests that prescribing is a decision-making process that is not sufficiently understood. By understanding more about prescribing processes and the implementation of research evidence, variation may more easily be understood and more effective interventions proposed. Methods An ethnographic study in three Scottish general practices with diverse organizational characteristics. Practices were ranked by their performance against Audit Scotland prescribing quality indicators, incorporating established best research evidence. Two practices of high prescribing quality and one practice of low prescribing quality were recruited. Participant observation, formal and informal interviews, and a review of practice documentation were employed. Results Practices ranked as high prescribing quality consistently made and applied macro and micro prescribing decisions, whereas the low-ranking practice only made micro prescribing decisions. Macro prescribing decisions were collective, policy decisions made considering research evidence in light of the average patient, one disease, condition, or drug. Micro prescribing decisions were made in consultation with the patient considering their views, preferences, circumstances and other conditions (if necessary). Although micro prescribing can operate independently, the implementation of evidence-based, quality prescribing was attributable to an interdependent relationship. Macro prescribing policy enabled prescribing decisions to be based on scientific evidence and applied consistently where possible. Ultimately, this influenced prescribing decisions that occur at the micro level in consultation with patients. Conclusion General practitioners in the higher prescribing quality practices made two different ‘types’ of prescribing decision; macro and micro. Macro prescribing informs micro prescribing and without a macro basis to draw upon the low-ranked practice had no effective mechanism to engage with, reflect on and implement relevant evidence. Practices that recognize these two levels of decision making about prescribing are more likely to be able to implement higher quality evidence. PMID:23799906
ERIC Educational Resources Information Center
Counsell, Serena J.; Edwards, A. David; Chew, Andrew T. M.; Anjari, Mustafa; Dyet, Leigh E.; Srinivasan, Latha; Boardman, James P.; Allsop, Joanna M.; Hajnal, Joseph V.; Rutherford, Mary A.; Cowan, Frances M.
2008-01-01
Survivors of preterm birth have a high incidence of neurodevelopmental impairment which is not explained by currently understood brain abnormalities. The aim of this study was to test the hypothesis that the neurodevelopmental abilities of 2-year-old children who were born preterm and who had no evidence of focal abnormality on conventional MR…
ERIC Educational Resources Information Center
Adamson, David M.
2010-01-01
Depression's effects on adolescent functioning and family burden are not well understood; there is also limited understanding of teens' and parents' attitudes and knowledge about depression, how these and other factors influence readiness for treatment, and the barriers to care that teens and their parents encounter. To address these knowledge…
On the Representational Systems Underlying Prospection: Evidence from the Event-Cueing Paradigm
ERIC Educational Resources Information Center
D'Argembeau, Arnaud; Demblon, Julie
2012-01-01
The ability to think about the future--prospection--is central to many aspects of human cognition and behavior, from planning and decision making, to self-control and the construction of a sense of identity. Yet, the exact nature of the representational systems underlying prospection is not fully understood. Recent findings point to the critical…
ERIC Educational Resources Information Center
Gone, Joseph P.
2009-01-01
Nineteen staff and clients in a Native American healing lodge were interviewed regarding the therapeutic approach used to address the legacy of Native American historical trauma. On the basis of thematic content analysis of interviews, 4 components of healing discourse emerged. First, clients were understood by their counselors to carry pain,…
ERIC Educational Resources Information Center
Avitabile, Ciro; Bobba, Matteo; Pariguana, Marco
2015-01-01
Parents and students from different socioeconomic backgrounds value differently school characteristics, but the reasons behind this preference heterogeneity are not well understood. In the context of the centralized school assignment system in Mexico City, this study analyzes how a large household income shock affects choices over high school…
Betty Kessler Lyman and the Indiana Federal Children's Theatre.
ERIC Educational Resources Information Center
Webb, Dorothy
1995-01-01
States that the special place that the Mickey Mouse Theater and its leader, Betty Lyman, occupy in the history of the Federal Theater project can best be understood in the economic and political context of the Depression. Concludes that there is little evidence to suggest Lyman's group contributed to the growth of children's theater in Indiana.…
ERIC Educational Resources Information Center
Longden, Eleanor; Madill, Anna; Waterman, Mitch G.
2012-01-01
Voice hearing (VH) is often regarded as pathognomic for schizophrenia. The purpose of this article is to review and integrate historical, clinical, epidemiological, and phenomenological evidence in order to suggest that VH may be more appropriately understood as a dissociative rather than a psychotic phenomenon. First, we discuss the lifetime…
Urban forest justice and the rights to wild foods, medicines, and materials in the city
Melissa R. Poe; Rebecca J. McClain; Marla Emery; Patrick Hurley
2013-01-01
Urban forests are multifunctional socio-ecological landscapes, yet some of their social benefits remain poorly understood. This paper draws on ethnographic evidence from Seattle, Washington to demonstrate that urban forests contain nontimber forest products that contribute a variety of wild foods, medicines, and materials for the wellbeing of urban residents. We show...
What Happens When a Teacher Uses Metalanguage to Teach Spelling?
ERIC Educational Resources Information Center
Daffern, Tessa
2017-01-01
While learning to spell in English is integral to becoming a literate writer, it is a complex and gradual skill to master. If English spelling is understood from a phonological, orthographic, and morphological perspective, its transparency becomes evident. The case study described in this article shines a light on an Australian Year 4 classroom…
ERIC Educational Resources Information Center
Warren, Zachary; Vehorn, Alison; Dohrmann, Elizabeth; Newsom, Cassandra; Taylor, Julie Lounds
2013-01-01
There is limited evidence surrounding the ability of families of children with autism spectrum disorders to access and implement recommended interventions following diagnosis. The distress a family may encounter with regard to inability to access recommended services is also poorly understood. In this study, we present preliminary data regarding…
Sex-specific association between infant diet and white matter integrity in 8-y-old children
USDA-ARS?s Scientific Manuscript database
Background: The American Academy of Pediatrics recommends breastfeeding, which is well known to promote cognitive and behavioral development. The evidence for why this occurs is not well understood. Methods: Fifty-six 7.5- to 8.5-y-old healthy children were breastfed (BF; n = 22, 10 males) or formul...
Spanish Rhotics: More Evidence of Gradience in the System
ERIC Educational Resources Information Center
Shelton, Michael
2013-01-01
The present study examines the nature of the Spanish rhotics experimentally, investigating the possibilities that the trill is best understood as deriving from an underlying geminate or that the tap and trill may be separate phonemes. In order to explore these two theories, a behavioral task was designed exploiting the absence of native words in…
Dense Neighborhoods and Mechanisms of Learning: Evidence from Children with Phonological Delay
ERIC Educational Resources Information Center
Gierut, Judith A.; Morrisette, Michele L.
2015-01-01
There is a noted advantage of dense neighborhoods in language acquisition, but the learning mechanism that drives the effect is not well understood. Two hypotheses--long-term auditory word priming and phonological working memory--have been advanced in the literature as viable accounts. These were evaluated in two treatment studies enrolling twelve…
ERIC Educational Resources Information Center
Davies, Lisa
2008-01-01
More than 800,000 Australians every year are affected by depression. Despite evidence that depression is manageable, that people can be successfully treated in individually appropriate ways and that earlier identification and treatment are associated with more rapid recovery, depression appears to be poorly recognised and understood. In this…
ERIC Educational Resources Information Center
Edwards, Susan; Cutter-Mackenzie, Amy
2013-01-01
Sustainability education is increasingly understood as necessary for young children. An important aspect of early childhood sustainability education is associated with how best to integrate the conceptual basis of sustainability education with existing play-based pedagogies. Play-based pedagogies can be understood as occurring along a continuum,…
Egidi, Giovanna; Caramazza, Alfonso
2014-12-01
According to recent research on language comprehension, the semantic features of a text are not the only determinants of whether incoming information is understood as consistent. Listeners' pre-existing affective states play a crucial role as well. The current fMRI experiment examines the effects of happy and sad moods during comprehension of consistent and inconsistent story endings, focusing on brain regions previously linked to two integration processes: inconsistency detection, evident in stronger responses to inconsistent endings, and fluent processing (accumulation), evident in stronger responses to consistent endings. The analysis evaluated whether differences in the BOLD response for consistent and inconsistent story endings correlated with self-reported mood scores after a mood induction procedure. Mood strongly affected regions previously associated with inconsistency detection. Happy mood increased sensitivity to inconsistency in regions specific for inconsistency detection (e.g., left IFG, left STS), whereas sad mood increased sensitivity to inconsistency in regions less specific for language processing (e.g., right med FG, right SFG). Mood affected more weakly regions involved in accumulation of information. These results show that mood can influence activity in areas mediating well-defined language processes, and highlight that integration is the result of context-dependent mechanisms. The finding that language comprehension can involve different networks depending on people's mood highlights the brain's ability to reorganize its functions. Copyright © 2014 Elsevier Inc. All rights reserved.
Age Differences in Self-Continuity: Converging Evidence and Directions for Future Research.
Löckenhoff, Corinna E; Rutt, Joshua L
2017-06-01
Life-span development is inherently linked to the perception of time and associated temporal construals. Such concepts are multi-faceted in nature and have important practical implications in areas such as time management, financial planning, or medical choices. A large body of research has documented age-related limitations in global time horizons, but age differences in other aspects of temporal construal are comparatively poorly understood. The present article draws attention to developmental trajectories of self-continuity, defined as perceived associations of one's present self with past and future selves. After considering historical roots and contemporary views on self-continuity, we turn to the life-span developmental literature and review several convergent streams of research that provide indirect evidence for age-related increases in self-continuity. We then consider a small body of recent studies which have directly assessed age differences in self-continuity and summarize our current understanding of this phenomenon including associations between explicit and implicit measures, symmetry between past and future self-continuity, and differentiation from other aspects of time perception. We conclude by highlighting open theoretical questions and considering the practical implications of an increased sense of self-continuity with advancing age. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Rapid Diffusion and Nanosegregation of Hydrogen in Magnesium Alloys from Exposure to Water.
Brady, Michael P; Ievlev, Anton V; Fayek, Mostafa; Leonard, Donovan N; Frith, Matthew G; Meyer, Harry M; Ramirez-Cuesta, Anibal J; Daemen, Luke L; Cheng, Yongqiang; Guo, Wei; Poplawsky, Jonathan D; Ovchinnikova, Olga S; Thomson, Jeffrey; Anovitz, Lawrence M; Rother, Gernot; Shin, Dongwon; Song, Guang-Ling; Davis, Bruce
2017-11-01
Hydrogen gas is formed when Mg corrodes in water; however, the manner and extent to which the hydrogen may also enter the Mg metal is poorly understood. Such knowledge is critical as stress corrosion cracking (SCC)/embrittlement phenomena limit many otherwise promising structural and functional uses of Mg. Here, we report via D 2 O/D isotopic tracer and H 2 O exposures with characterization by secondary ion mass spectrometry, inelastic neutron scattering vibrational spectrometry, electron microscopy, and atom probe tomography techniques direct evidence that hydrogen rapidly penetrated tens of micrometers into Mg metal after only 4 h of exposure to water at room temperature. Further, technologically important microalloying additions of <1 wt % Zr and Nd used to improve the manufacturability and mechanical properties of Mg significantly increased the extent of hydrogen ingress, whereas Al additions in the 2-3 wt % range did not. Segregation of hydrogen species was observed at regions of high Mg/Zr/Nd nanoprecipitate density and at Mg(Zr) metastable solid solution microstructural features. We also report evidence that this ingressed hydrogen was unexpectedly present in the alloy as nanoconfined, molecular H 2 . These new insights provide a basis for strategies to design Mg alloys to resist SCC in aqueous environments as well as potentially impact functional uses such as hydrogen storage where increased hydrogen uptake is desired.
Altered resting-state connectivity within default mode network associated with late chronotype.
Horne, Charlotte Mary; Norbury, Ray
2018-04-20
Current evidence suggests late chronotype individuals have an increased risk of developing depression. However, the underlying neural mechanisms of this association are not fully understood. Forty-six healthy, right-handed individuals free of current or previous diagnosis of depression, family history of depression or sleep disorder underwent resting-state functional Magnetic Resonance Imaging (rsFMRI). Using an Independent Component Analysis (ICA) approach, the Default Mode Network (DMN) was identified based on a well validated template. Linear effects of chronotype on DMN connectivity were tested for significance using non-parametric permutation tests (applying 5000 permutations). Sleep quality, age, gender, measures of mood and anxiety, time of scan and cortical grey matter volume were included as covariates in the regression model. A significant positive correlation between chronotype and functional connectivity within nodes of the DMN was observed, including; bilateral PCC and precuneus, such that later chronotype (participants with lower rMEQ scores) was associated with decreased connectivity within these regions. The current results appear consistent with altered DMN connectivity in depressed patients and weighted evidence towards reduced DMN connectivity in other at-risk populations which may, in part, explain the increased vulnerability for depression in late chronotype individuals. The effect may be driven by self-critical thoughts associated with late chronotype although future studies are needed to directly investigate this. Copyright © 2018 Elsevier Ltd. All rights reserved.
Improved cerebral energetics and ketone body metabolism in db/db mice
Andersen, Jens V; Christensen, Sofie K; Nissen, Jakob D
2016-01-01
It is becoming evident that type 2 diabetes mellitus is affecting brain energy metabolism. The importance of alternative substrates for the brain in type 2 diabetes mellitus is poorly understood. The aim of this study was to investigate whether ketone bodies are relevant candidates to compensate for cerebral glucose hypometabolism and unravel the functionality of cerebral mitochondria in type 2 diabetes mellitus. Acutely isolated cerebral cortical and hippocampal slices of db/db mice were incubated in media containing [U-13C]glucose, [1,2-13C]acetate or [U-13C]β-hydroxybutyrate and tissue extracts were analysed by mass spectrometry. Oxygen consumption and ATP synthesis of brain mitochondria of db/db mice were assessed by Seahorse XFe96 and luciferin-luciferase assay, respectively. Glucose hypometabolism was observed for both cerebral cortical and hippocampal slices of db/db mice. Significant increased metabolism of [1,2-13C]acetate and [U-13C]β-hydroxybutyrate was observed for hippocampal slices of db/db mice. Furthermore, brain mitochondria of db/db mice exhibited elevated oxygen consumption and ATP synthesis rate. This study provides evidence of several changes in brain energy metabolism in type 2 diabetes mellitus. The increased hippocampal ketone body utilization and improved mitochondrial function in db/db mice, may act as adaptive mechanisms in order to maintain cerebral energetics during hampered glucose metabolism. PMID:28058963
NASA Astrophysics Data System (ADS)
Oakley, J. R.; Patterson, W. P.
2008-12-01
Global warming models often contain a prediction of changes in precipitation, yet modern moisture cycling is poorly understood. Stable oxygen and deuterium isotope values of several thousand lake and river water samples collected from 2004 to 2008 throughout Canada and the Northern United States provide a means to evaluate variations in the movement of moisture across the northern North American continent. Our particular focus is on the moisture tracking in the province of Saskatchewan. The dominant moisture source for Saskatchewan is the Gulf of Mexico, though precipitation contains some water from the Pacific and Arctic Oceans as well. By sampling locations multiple times, we established time series of isotope variability that we can relate to meteorological variation. A series of cross-plots of oxygen to deuterium isotopes for each year exhibits an increase in slope from year to year that reflects an increase in humidity and/or precipitation throughout the Prairies from 2004 to 2008. We define the influence of temperature, precipitation and humidity on the change in slope for each suite of samples. Ultimately, by combining our evidence of moisture transport with a grid of long-term secular records from lakes, speleothems and tree-ring isotope variability, we can not only reconstruct changes in atmospheric circulation through time, but also better predict what will happen in the future under various global climate change scenarios.
Myocardial Hypertrophy and Its Role in Heart Failure with Preserved Ejection Fraction
Heinzel, Frank R.; Hohendanner, Felix; Jin, Ge; Sedej, Simon; Edelmann, Frank
2015-01-01
Left ventricular hypertrophy (LVH) is the most common myocardial structural abnormality associated with heart failure with preserved ejection fraction (HFpEF). LVH is driven by neurohumoral activation, increased mechanical load and cytokines associated with arterial hypertension, chronic kidney disease, diabetes and other co-morbidities. Here we discuss the experimental and clinical evidence that links LVH to diastolic dysfunction and qualifies LVH as one diagnostic marker for HFpEF. Mechanisms leading to diastolic dysfunction in LVH are incompletely understood but may include extracellular matrix changes, vascular dysfunction as well as altered cardiomyocyte mechano-elastical properties. Beating cardiomyocytes from HFpEF patients have not yet been studied, but we and others have shown increased Ca2+ turnover and impaired relaxation in cardiomyocytes from hypertrophied hearts. Structural myocardial remodeling can lead to heterogeneity in regional myocardial contractile function, which contributes to diastolic dysfunction in HFpEF. In the clinical setting of patients with compound co-morbidities, diastolic dysfunction may occur independently of LVH. This may be one explanation why current approaches to reduce LVH have not been effective to improve symptoms and prognosis in HFpEF. Exercise training on the other hand, in clinical trials improved exercise tolerance and diastolic function but did not reduce LVH. Thus, current clinical evidence does not support regression of LVH as a surrogate marker for (short-term) improvement of HFpEF. PMID:26183480
Rapid Diffusion and Nanosegregation of Hydrogen in Magnesium Alloys from Exposure to Water
Brady, Michael P.; Ievlev, Anton V.; Fayek, Mostafa; ...
2017-10-10
Hydrogen gas is formed when Mg corrodes in water; however, the manner and extent to which the hydrogen may also enter the Mg metal is poorly understood. Such knowledge is critical as stress corrosion cracking (SCC)/embrittlement phenomena limit many otherwise promising structural and functional uses of Mg. Here, we report via D 2O/D isotopic tracer and H 2O exposures with characterization by secondary ion mass spectrometry, inelastic neutron scattering vibrational spectrometry, electron microscopy, and atom probe tomography techniques direct evidence that hydrogen rapidly penetrated tens of micrometers into Mg metal after only 4 h of exposure to water at roommore » temperature. Further, technologically important microalloying additions of <1 wt % Zr and Nd used to improve the manufacturability and mechanical properties of Mg significantly increased the extent of hydrogen ingress, whereas Al additions in the 2–3 wt % range did not. Segregation of hydrogen species was observed at regions of high Mg/Zr/Nd nanoprecipitate density and at Mg(Zr) metastable solid solution microstructural features. We also report evidence that this ingressed hydrogen was unexpectedly present in the alloy as nanoconfined, molecular H 2. These new insights provide a basis for strategies to design Mg alloys to resist SCC in aqueous environments as well as potentially impact functional uses such as hydrogen storage where increased hydrogen uptake is desired.« less
Yang, Zhenzhen; Zhang, Yeting; Wafula, Eric K.; Honaas, Loren A.; Ralph, Paula E.; Jones, Sam; Clarke, Christopher R.; Liu, Siming; Su, Chun; Zhang, Huiting; Altman, Naomi S.; Schuster, Stephan C.; Timko, Michael P.; Yoder, John I.; dePamphilis, Claude W.
2016-01-01
Horizontal gene transfer (HGT) is the transfer of genetic material across species boundaries and has been a driving force in prokaryotic evolution. HGT involving eukaryotes appears to be much less frequent, and the functional implications of HGT in eukaryotes are poorly understood. We test the hypothesis that parasitic plants, because of their intimate feeding contacts with host plant tissues, are especially prone to horizontal gene acquisition. We sought evidence of HGTs in transcriptomes of three parasitic members of Orobanchaceae, a plant family containing species spanning the full spectrum of parasitic capabilities, plus the free-living Lindenbergia. Following initial phylogenetic detection and an extensive validation procedure, 52 high-confidence horizontal transfer events were detected, often from lineages of known host plants and with an increasing number of HGT events in species with the greatest parasitic dependence. Analyses of intron sequences in putative donor and recipient lineages provide evidence for integration of genomic fragments far more often than retro-processed RNA sequences. Purifying selection predominates in functionally transferred sequences, with a small fraction of adaptively evolving sites. HGT-acquired genes are preferentially expressed in the haustorium—the organ of parasitic plants—and are strongly biased in predicted gene functions, suggesting that expression products of horizontally acquired genes are contributing to the unique adaptive feeding structure of parasitic plants. PMID:27791104
Transgenerational effects of insecticides-implications for rapid pest evolution in agroecosystems.
Brevik, Kristian; Lindström, Leena; McKay, Stephanie D; Chen, Yolanda H
2018-04-01
Although pesticides are a major selective force in driving the evolution of insect pests, the evolutionary processes that give rise to insecticide resistance remain poorly understood. Insecticide resistance has been widely observed to increase with frequent and intense insecticide exposure, but can be lost following the relaxation of insecticide use. One possible but rarely explored explanation is that insecticide resistance may be associated with epigenetic modifications, which influence the patterning of gene expression without changing underlying DNA sequence. Epigenetic modifications such as DNA methylation, histone modifications, and small RNAs have been observed to be heritable in arthropods, but their role in the context of rapid evolution of insecticide resistance remain poorly understood. Here, we discuss evidence supporting how: firstly, insecticide-induced effects can be transgenerationally inherited; secondly, epigenetic modifications are heritable; and thirdly, epigenetic modifications are responsive to pesticide and xenobiotic stress. Therefore, pesticides may drive the evolution of resistance via epigenetic processes. Moreover, insect pests primed by pesticides may be more tolerant of other stress, further enhancing their success in adapting to agroecosystems. Resolving the role of epigenetic modifications in the rapid evolution of insect pests has the potential to lead to new approaches for integrated pest management as well as improve our understanding of how anthropogenic stress may drive the evolution of insect pests. Copyright © 2018 Elsevier Inc. All rights reserved.
Have we seen the geneticisation of society? Expectations and evidence.
Weiner, Kate; Martin, Paul; Richards, Martin; Tutton, Richard
2017-09-01
Abby Lippman's geneticisation thesis, of the early 1990s, argued and anticipated that with the rise of genetics, increasing areas of social and health related activities would come to be understood and defined in genetic terms leading to major changes in society, medicine and health care. We review the considerable literature on geneticisation and consider how the concept stands both theoretically and empirically across scientific, clinical, popular and lay discourse and practice. Social science scholarship indicates that relatively little of the original claim of the geneticisation thesis has been realised, highlighting the development of more complex and dynamic accounts of disease in scientific discourse and the complexity of relationships between bioscientific, clinical and lay understandings. This scholarship represents a shift in social science understandings of the processes of sociotechnical change, which have moved from rather simplistic linear models to an appreciation of disease categories as multiply understood. Despite these shifts, we argue that a genetic imaginary persists, which plays a performative role in driving investments in new gene-based developments. Understanding the enduring power of this genetic imaginary and its consequences remains a key task for the social sciences, one which treats ongoing genetic expectations and predictions in a sceptical yet open way. © 2017 The Authors. Sociology of Health & Illness published by John Wiley & Sons Ltd on behalf of Foundation for SHIL.
Equine Welfare in England and Wales: Exploration of Stakeholders' Understanding.
Horseman, Susan V; Buller, Henry; Mullan, Siobhan; Knowles, Toby G; Barr, Alistair R S; Whay, Helen R
2017-01-01
Investigating how those responsible for the care of nonhuman animals understand the concept of animal welfare is important for animal welfare improvement. In-depth interviews with 31 equine stakeholders were used to explore their perceptions and understanding of welfare. The results showed the stakeholders understood the concept of welfare in 4 ways. Firstly, welfare was understood in terms of the provision of resources-for example, food. Secondly, a "horse-centered" understanding of welfare was articulated; this understanding included the horses' mental state and was linked to natural behavior. Thirdly, the word welfare had negative connotations, and for some, good welfare was achieved through avoidance of negative states. Finally, interviewees discussed incidents that occurred in their own familiar contexts but suggested that these were not welfare problems. Evidence indicated that the ways in which equine stakeholders understood the concept of welfare might have been acting as a barrier to the alleviation of some equine welfare problems. There is a need for strategies aimed at improving equine welfare to consider stakeholder constructs of welfare and the ways in which these constructs are generated and acted upon.
Oversimplification in the study of emotional memory
Bennion, Kelly A.; Ford, Jaclyn H.; Murray, Brendan D.; Kensinger, Elizabeth A.
2014-01-01
This Short Review critically evaluates three hypotheses about the effects of emotion on memory: First, emotion usually enhances memory. Second, when emotion does not enhance memory, this can be understood by the magnitude of physiological arousal elicited, with arousal benefiting memory to a point but then having a detrimental influence. Third, when emotion facilitates the processing of information, this also facilitates the retention of that same information. For each of these hypotheses, we summarize the evidence consistent with it, present counter-evidence suggesting boundary conditions for the effect, and discuss the implications for future research. PMID:24007950
Mental health services then and now.
Mechanic, David
2007-01-01
Over the past twenty-five years, psychiatric services have shifted from hospital to community. Managed care reinforces this trend. Mental illness is better understood and less stigmatized, and services are more commonly used. But many in need do not receive care consistent with evidence-based standards, or at all. Challenges are greatest for people with serious and persistent mental illnesses who depend on generic health and welfare programs and integrated services. Evidence-based rehabilitative care is often unavailable. Failures in community care lead to arrest; jail diversion and treatment are required. Despite progress, implementing an effective, patient-centered care system remains a formidable challenge.
Is receptor oligomerization causally linked to activation of the EGF receptor kinase?
NASA Technical Reports Server (NTRS)
Rintoul, D. A.; Spooner, B. S. (Principal Investigator)
1992-01-01
Transduction of a signal from an extracellular peptide hormone to produce an intracellular response is often mediated by a cell surface receptor, which is usually a glycoprotein. The secondary intracellular signal(s) generated after hormone binding to the receptor have been intensively studied. The nature of the primary signal generated by ligand binding to the receptor is understood less well in most cases. The particular case of the epidermal growth factor (EGF) receptor is analyzed, and evidence for or against two dissimilar models of primary signal transduction is reviewed. Evidence for the most widely accepted current model is found to be unconvincing. Evidence for the other model is substantial but indirect; a direct test of this model remains to be done.
Towards evidence-based practice in medical training: making evaluations more meaningful.
Drescher, Uta; Warren, Fiona; Norton, Kingsley
2004-12-01
The evaluation of training is problematic and the evidence base inconclusive. This situation may arise for 2 main reasons: training is not understood as a complex intervention and, related to this, the evaluation methods applied are often overly simplistic. This paper makes the case for construing training, especially in the field of specialist medical education, as a complex intervention. It also selectively reviews the available literature in order to match evaluative techniques with the demonstrated complexity. Construing training as a complex intervention can provide a framework for selecting the most appropriate methodology to evaluate a given training intervention and to appraise the evidence base for training fairly, choosing from among both quantitative and qualitative approaches and applying measurement at multiple levels of training impact.
Geophysical, archaeological and historical evidence support a solar-output model for climate change
Perry, C.A.; Hsu, K.J.
2000-01-01
Although the processes of climate change are not completely understood, an important causal candidate is variation in total solar output. Reported cycles in various climate-proxy data show a tendency to emulate a fundamental harmonic sequence of a basic solar-cycle length (11 years) multiplied by 2(N) (where N equals a positive or negative integer). A simple additive model for total solar-output variations was developed by superimposing a progression of fundamental harmonic cycles with slightly increasing amplitudes. The timeline of the model was calibrated to the Pleistocene/Holocene boundary at 9,000 years before present. The calibrated model was compared with geophysical, archaeological, and historical evidence of warm or cold climates during the Holocene. The evidence of periods of several centuries of cooler climates worldwide called 'little ice ages,' similar to the period anno Domini (A.D.) 1280-1860 and reoccurring approximately every 1,300 years, corresponds well with fluctuations in modeled solar output. A more detailed examination of the climate sensitive history of the last 1,000 years further supports the model. Extrapolation of the model into the future suggests a gradual cooling during the next few centuries with intermittent minor warmups and a return to near little-ice-age conditions within the next 500 years. This cool period then may be followed approximately 1,500 years from now by a return to altithermal conditions similar to the previous Holocene Maximum.
Quantifying the dose-response of walking in reducing coronary heart disease risk: meta-analysis.
Zheng, Henry; Orsini, Nicola; Amin, Janaki; Wolk, Alicja; Nguyen, Van Thi Thuy; Ehrlich, Fred
2009-01-01
The evidence for the efficacy of walking in reducing the risk of and preventing coronary heart disease (CHD) is not completely understood. This meta-analysis aimed to quantify the dose-response relationship between walking and CHD risk reduction for both men and women in the general population. Studies on walking and CHD primary prevention between 1954 and 2007 were identified through Medline, SportDiscus and the Cochrane Database of Systematic Reviews. Random-effect meta-regression models were used to pool the relative risks from individual studies. A total of 11 prospective cohort studies and one randomized control trial study met the inclusion criteria, with 295,177 participants free of CHD at baseline and 7,094 cases at follow-up. The meta-analysis indicated that an increment of approximately 30 min of normal walking a day for 5 days a week was associated with 19% CHD risk reduction (95% CI = 14-23%; P-heterogeneity = 0.56; I (2) = 0%). We found no evidence of heterogeneity between subgroups of studies defined by gender (P = 0.67); age of the study population (P = 0.52); or follow-up duration (P = 0.77). The meta-analysis showed that the risk for developing CHD decreases as walking dose increases. Walking should be prescribed as an evidence-based effective exercise modality for CHD prevention in the general population.
Aerogeophysical evidence for active volcanism beneath the West Antarctic Ice Sheet
NASA Technical Reports Server (NTRS)
Blankenship, Donald D.; Bell, Robin E.; Hodge, Steven M.; Brozena, John M.; Behrendt, John C.
1993-01-01
Although it is widely understood that the collapse of the West Antarctic Ice Sheet (WAIS) would cause a global sea-level rise of 6 m, there continues to be considerable debate about the response of this ice sheet to climate change. The stability of the WAIS, which is characterized by a bed grounded well below sea level, may depend on geologically controlled conditions at the base, which are independent of climate. Ice streams moving up to 750 m/yr disperse material from the interior through to the oceans. As these ice streams tend to buffer the reservoir of slow-moving inland ice from exposure to oceanic degradation, understanding the ice-streaming process is important for evaluating WAIS stability. There is strong evidence that ice streams slide on a lubricating layer of water-saturated till. Development of this basal layer requires both water and easily eroded sediments. Active lithospheric extension may elevate regional heat flux, increase basal melting, and trigger ice streaming. If a geologically defined boundary with a sharp contrast in geothermal flux exists beneath the WAIS, ice streams may only be capable of operating as a buffer over a restricted region. Should ocean waters penetrate beyond this boundary, the ice-stream buffer would disappear, possibly triggering a collapse of the inland ice reservoir. Aerogeophysical evidence for active volcanism and elevated heat flux beneath the WAIS near the critical region where ice streaming begins is presented.
NASA Astrophysics Data System (ADS)
Ling, Zongxin; Liu, Xia; Jia, Xiaoyun; Cheng, Yiwen; Luo, Yueqiu; Yuan, Li; Wang, Yuezhu; Zhao, Chunna; Guo, Shu; Li, Lanjuan; Xu, Xiwei; Xiang, Charlie
2014-12-01
Increasing evidence suggests that altered intestinal microbial composition and function result in an increased risk of Clostridium difficile-associated diarrhoea (CDAD); however, the specific changes of intestinal microbiota in children suffering from CDAD and their associations with C. difficile strain toxigenicity are poorly understood. High-throughput pyrosequencing showed that reduced faecal bacterial diversity and dramatic shifts of microbial composition were found in children with CDAD. The Firmicutes/Bacteroidetes ratio was increased significantly in patients with CDAD, which indicated that dysbiosis of faecal microbiota was closely associated with CDAD. C. difficile infection resulted in an increase in lactate-producing phylotypes, with a corresponding decrease in butyrate-producing bacteria. The decrease in butyrate and lactate buildup impaired intestinal colonisation resistance, which increased the susceptibility to C. difficile colonisation. Strains of C. difficile which were positive for both toxin A and toxin B reduced faecal bacterial diversity to a greater degree than strains that were only toxin B-positive, and were associated with unusually abundant Enterococcus, which implies that the C. difficile toxins have different impacts on the faecal microbiota of children. Greater understanding of the relationships between disruption of the normal faecal microbiota and colonisation with C. difficile that produces different toxins might lead to improved treatment.
Epigenetic regulation of miRNA-cancer stem cells nexus by nutraceuticals.
Ahmad, Aamir; Li, Yiwei; Bao, Bin; Kong, Dejuan; Sarkar, Fazlul H
2014-01-01
Nutraceuticals, the bioactive food components represented by many naturally occurring dietary compounds, have been investigated for a few decades for their numerous beneficial effects, including their anticancer properties. The initial interest in the cancer-preventing/therapeutic ability of these agents was based on their ability to affect multiple signaling pathways that are deregulated in cancer cells. With a shift in the focus of cancer research to the emerging areas such as epigenetic regulation, microRNAs (miRNAs) and the cancer stem cells (CSCs), nutraceuticals initially appeared out of place. However, research investigations over the last several years have slowly but firmly presented evidence that supports a relevance of these agents in modern day research. While nutraceuticals are increasingly being realized to alter miRNA/CSCs expression and function, the molecular mechanism(s) are not very clearly understood. Epigenetic regulation is one mechanism by which these agents exert their anticancer effects. In this focused mini review, we summarize our current understanding of epigenetic regulation of miRNAs and CSCs by nutraceuticals. We discuss both direct and indirect evidences that support such an activity of these compounds. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Farzan, Faranak; Pascual-Leone, Alvaro; Schmahmann, Jeremy D.; Halko, Mark
2016-01-01
Growing evidence suggests that sensory, motor, cognitive and affective processes map onto specific, distributed neural networks. Cerebellar subregions are part of these networks, but how the cerebellum is involved in this wide range of brain functions remains poorly understood. It is postulated that the cerebellum contributes a basic role in brain functions, helping to shape the complexity of brain temporal dynamics. We therefore hypothesized that stimulating cerebellar nodes integrated in different networks should have the same impact on the temporal complexity of cortical signals. In healthy humans, we applied intermittent theta burst stimulation (iTBS) to the vermis lobule VII or right lateral cerebellar Crus I/II, subregions that prominently couple to the dorsal-attention/fronto-parietal and default-mode networks, respectively. Cerebellar iTBS increased the complexity of brain signals across multiple time scales in a network-specific manner identified through electroencephalography (EEG). We also demonstrated a region-specific shift in power of cortical oscillations towards higher frequencies consistent with the natural frequencies of targeted cortical areas. Our findings provide a novel mechanism and evidence by which the cerebellum contributes to multiple brain functions: specific cerebellar subregions control the temporal dynamics of the networks they are engaged in. PMID:27009405
Diet and prostate cancer - a holistic approach to management.
Cheetham, Philippa J; Katz, Aaron E
2011-10-01
There is now increasing evidence from epidemiologic surveys and from laboratory, intervention, and case-control studies that diet and lifestyle plays a crucial role in prostate cancer biology and tumorigenesis. This applies to both the development and progression of prostate cancer, although in many cases the specific initiating factors in the diet are poorly understood. Conversely, many nutrients and herbs also show significant promise in helping to treat prostate cancer by slowing progression and reducing recurrence, ultimately reducing the risk of morbidity and mortality from the disease. Furthermore for all grades of prostate cancer, nutritional interventions complement conventional treatment to improve response and quality of life. Slowing or even reversing the progression of, high-grade prostate intraepithelial neoplasia [HGPIN]). with chemo-preventative agents could be the best primary defense against prostate cancer, preventing it from occurring in the first place. The information given in this review about prostate cancer chemoprevention summarizes the key evidence for the role of different dietary components and their effect on prostate cancer prevention and progression. Most nutritional chemoprevention agents also have the added benefit of being beneficial for the cardiovascular system, bone health and for the prevention of other cancers.
Tharmalingam, Sujeenthar; Sreetharan, Shayenthiran; Kulesza, Adomas V; Boreham, Douglas R; Tai, T C
2017-10-01
Ionizing radiation exposure from medical diagnostic imaging has greatly increased over the last few decades. Approximately 80% of patients who undergo medical imaging are exposed to low-dose ionizing radiation (LDIR). Although there is widespread consensus regarding the harmful effects of high doses of radiation, the biological effects of low-linear energy transfer (LET) LDIR is not well understood. LDIR is known to promote oxidative stress, however, these levels may not be large enough to result in genomic mutations. There is emerging evidence that oxidative stress causes heritable modifications via epigenetic mechanisms (DNA methylation, histone modification, noncoding RNA regulation). These epigenetic modifications result in permanent cellular transformations without altering the underlying DNA nucleotide sequence. This review summarizes the major concepts in the field of epigenetics with a focus on the effects of low-LET LDIR (<100 mGy) and oxidative stress on epigenetic gene modification. In this review, we show evidence that suggests that LDIR-induced oxidative stress provides a mechanistic link between LDIR and epigenetic gene regulation. We also discuss the potential implication of LDIR exposure during pregnancy where intrauterine fetal development is highly susceptible to oxidative stress-induced epigenetic programing.
Nutritional approach to preeclampsia prevention.
Achamrah, Najate; Ditisheim, Agnès
2018-05-01
Although not fully understood, the physiopathology of preeclampsia is thought to involve an abnormal placentation, diffuse endothelial cell dysfunction and increased systemic inflammation. As micronutrients play a key role in placental endothelial function, oxidative stress and expression of angiogenic factors, periconceptional micronutrient supplementation has been proposed to reduce the risk of preeclampsia. However, recent studies reported conflicting results. Calcium intake (>1 g/day) may reduce the risk of preeclampsia in women with low-calcium diet. Data from recently updated Cochrane reviews did not support routine supplementation of vitamins C, E or D for either the prevention or treatment of preeclampsia. Evidences are also poor to support zinc or folic acid supplementation for preeclampsia prevention. Dark chocolate, flavonoid-rich food, and long-chain polyunsaturated fatty acids might also be candidates for prevention of preeclampsia. Through antioxidant, anti-inflammatory or vasoactive proprieties, micronutrients are good candidates for preeclampsia prevention. Calcium supplementation is recommended to prevent preeclampsia in women with low-calcium intake. Despite positive clinical and in-vitro data, strong evidence to support periconceptional supplementation of other micronutrients for preeclampsia risk-reduction is still lacking. Further studies are also needed to evaluate the benefit of nutritional supplementation such as chocolate and long-chain polyunsaturated fatty acids.
Phthalates and other additives in plastics: human exposure and associated health outcomes
Meeker, John D.; Sathyanarayana, Sheela; Swan, Shanna H.
2009-01-01
Concern exists over whether additives in plastics to which most people are exposed, such as phthalates, bisphenol A or polybrominated diphenyl ethers, may cause harm to human health by altering endocrine function or through other biological mechanisms. Human data are limited compared with the large body of experimental evidence documenting reproductive or developmental toxicity in relation to these compounds. Here, we discuss the current state of human evidence, as well as future research trends and needs. Because exposure assessment is often a major weakness in epidemiological studies, and in utero exposures to reproductive or developmental toxicants are important, we also provide original data on maternal exposure to phthalates during and after pregnancy (n = 242). Phthalate metabolite concentrations in urine showed weak correlations between pre- and post-natal samples, though the strength of the relationship increased when duration between the two samples decreased. Phthalate metabolite levels also tended to be higher in post-natal samples. In conclusion, there is a great need for more human studies of adverse health effects associated with plastic additives. Recent advances in the measurement of exposure biomarkers hold much promise in improving the epidemiological data, but their utility must be understood to facilitate appropriate study design. PMID:19528058
Mutations in PRKN and SNCA Genes Important for the Progress of Parkinson's Disease.
Oczkowska, Anna; Kozubski, Wojciech; Lianeri, Margarita; Dorszewska, Jolanta
2013-12-01
Although Parkinson's disease (PD) was first described almost 200 years ago, it remains an incurable disease with a cause that is not fully understood. Nowadays it is known that disturbances in the structure of pathological proteins in PD can be caused by more than environmental and genetic factors. Despite numerous debates and controversies in the literature about the role of mutations in the SNCA and PRKN genes in the pathogenesis of PD, it is evident that these genes play a key role in maintaining dopamine (DA) neuronal homeostasis and that the dysfunction of this homeostasis is relevant to both familial (FPD) and sporadic (SPD) PD with different onset. In recent years, the importance of alphasynuclein (ASN) in the process of neurodegeneration and neuroprotective function of the Parkin is becoming better understood. Moreover, there have been an increasing number of recent reports indicating the importance of the interaction between these proteins and their encoding genes. Among others interactions, it is suggested that even heterozygous substitution in the PRKN gene in the presence of the variants +2/+2 or +2/+3 of NACP-Rep1 in the SNCA promoter, may increase the risk of PD manifestation, which is probably due to ineffective elimination of over-expressed ASN by the mutated Parkin protein. Finally, it seems that genetic testing may be an important part of diagnostics in patients with PD and may improve the prognostic process in the course of PD. However, only full knowledge of the mechanism of the interaction between the genes associated with the pathogenesis of PD is likely to help explain the currently unknown pathways of selective damage to dopaminergic neurons in the course of PD.
Mutations in PRKN and SNCA Genes Important for the Progress of Parkinson’s Disease
Oczkowska, Anna; Kozubski, Wojciech; Lianeri, Margarita; Dorszewska, Jolanta
2013-01-01
Although Parkinson’s disease (PD) was first described almost 200 years ago, it remains an incurable disease with a cause that is not fully understood. Nowadays it is known that disturbances in the structure of pathological proteins in PD can be caused by more than environmental and genetic factors. Despite numerous debates and controversies in the literature about the role of mutations in the SNCA and PRKN genes in the pathogenesis of PD, it is evident that these genes play a key role in maintaining dopamine (DA) neuronal homeostasis and that the dysfunction of this homeostasis is relevant to both familial (FPD) and sporadic (SPD) PD with different onset. In recent years, the importance of alphasynuclein (ASN) in the process of neurodegeneration and neuroprotective function of the Parkin is becoming better understood. Moreover, there have been an increasing number of recent reports indicating the importance of the interaction between these proteins and their encoding genes. Among others interactions, it is suggested that even heterozygous substitution in the PRKN gene in the presence of the variants +2/+2 or +2/+3 of NACP-Rep1 in the SNCA promoter, may increase the risk of PD manifestation, which is probably due to ineffective elimination of over-expressed ASN by the mutated Parkin protein. Finally, it seems that genetic testing may be an important part of diagnostics in patients with PD and may improve the prognostic process in the course of PD. However, only full knowledge of the mechanism of the interaction between the genes associated with the pathogenesis of PD is likely to help explain the currently unknown pathways of selective damage to dopaminergic neurons in the course of PD. PMID:24532983
δ 13C of free and macromolecular aromatic structures in the murchison meteorite
NASA Astrophysics Data System (ADS)
Sephton, M. A.; Pillinger, C. T.; Gilmour, I.
1998-05-01
Analyses of the organic compounds in the Murchison meteorite have led to a greater understanding of the nature of extraterrestrial organic materials. However, the relationship between low and high molecular weight material remains poorly understood. To investigate this relationship, untreated Murchison was subjected to supercritical fluid extraction (SFE) to obtain the free organic components in the meteorite. Toluene and other volatile aromatic hydrocarbons dominated the extract, and the carbon isotopic composition of these molecules was determined by gas chromatography-isotope ratio-mass spectrometry (GCIRMS). δ 13C values of the aromatic hydrocarbons ranged from -28.8 to -5.8‰. These compounds displayed a 13C-enrichment with increasing carbon number suggesting an origin by cracking. The high molecular weight organic material in the meteorite was isolated and subjected to hydrous pyrolysis. This procedure produced a number of aromatic products, the majority of which were volatile aromatic hydrocarbons, particularly toluene. SFE was used to extract and successfully retain them. This enabled the first carbon isotopic analysis of this poorly understood material to be performed at the molecular level by GCIRMS. δ 13C values for aromatic pyrolysis products occupied a range from -24.6 to -5.6‰. The trend of 13C-enrichment with increasing carbon number, observed in the free compounds, was also evident in the macromolecular fragments. Furthermore, the organic fragments of the macromolecular material were consistently 13C-enriched when compared to structurally identical free molecules. This suggested that the free aromatic hydrocarbons in Murchison were produced by the preterrestrial degradation of the organic macromolecular material. This natural degradation event was extended by the hydrous pyrolysis experiment.
The Missing Link between Faces and Names: Evidence from Alzheimer's Disease Patients
ERIC Educational Resources Information Center
Calabria, Marco; Sabio, Alicia; Martin, Clara; Hernandez, Mireia; Juncadella, Montserrat; Gascon-Bayarri, Jordi; Rene, Ramon; Ortiz-Gil, Jordi; Ugas, Lidia; Costa, Albert
2012-01-01
Retrieval of proper names is a cause of concern and complaint among elderly adults and it is an early symptom of patients suffering from neurodegenerative diseases such as Alzheimer's disease (AD). While it is well established that AD patients have deficits of proper name retrieval, the nature of such impairment is not yet fully understood.…
Towards Understanding Different Faces of School Violence in Different "Worlds" of One Country
ERIC Educational Resources Information Center
Jacobs, Lynette
2013-01-01
The legacy of South Africa's destructive history is still evident in the different worlds in which South Africans live. Quality education is compromised by violence occurring in schools and role-players must face school violence and take steps to deal with it. This can only be done if school violence is deeply understood within the various school…
ERIC Educational Resources Information Center
Immordino-Yang, Mary Helen
2008-01-01
From the pragmatists to the neo-Piagetians, development has been understood to involve cycles of perception and action--the internalization of interactions with the world and the construction of skills for acting in the world. From a neurobiological standpoint, new evidence suggests that neural activities related to action and perception converge…
Do State Subsidies for Public Universities Favor the Affluent? Evidence Speaks Reports, Vol 1, #23
ERIC Educational Resources Information Center
Delisle, Jason; Dancy, Kim
2016-01-01
Public universities typically charge students less than the full cost of education, using funds from state and local government and other sources to cover the difference. This indirect subsidy is one of the largest forms of aid in America's higher education system but is less understood in the policy community than grants and loans, which are…
ERIC Educational Resources Information Center
Barahona, Malba
2017-01-01
The demonstrable potential of team teaching as a productive mechanism for developing collaborative teacher learning is now broadly understood in the field of teacher education. However, there is less evidence of the use of such collaborative teaching as a means of strengthening initial foreign/second language teacher education. This paper reports…
ERIC Educational Resources Information Center
Glewwe, Paul
Mothers' education is frequently found to be positively correlated with child health and nutrition in developing countries, and yet the causal mechanisms are poorly understood. An examination was conducted of the role played by three mechanisms in this process: formal education that directly teaches health knowledge to future mothers; literacy and…
ERIC Educational Resources Information Center
Chudgar, Amita; Creed, Benjamin
2016-01-01
The private school sector in India has grown significantly but the equity implications of this growth are not well understood. Traditionally private schools have been patronised by more educated and better-off families. Evidence also suggests a preference for enrolling male children in private schools. With the growth in the private school sector…
Examining Teachers' Use of iPads: Comfort Level, Perception, and Use
ERIC Educational Resources Information Center
Liu, Min; Navarrete, Cesar C.; Scordino, Robert; Kang, Jina; Ko, Yujung; Lim, Mihyun
2016-01-01
While there is evidence of the growing popularity of iPads and other tablets in K-12 education, little is understood about how teachers use these devices in their instruction. This study examines 342 teachers' comfort level with and perception toward iPad use and any changes that occurred over the implementation year. Using a mixed-methods design,…
Ethical evaluation of decision-making for distribution of health resources in China.
Guo-Ping, Wang
2007-06-01
Since distribution of health resources involves various aspects of ethics, the evaluation of ethical problems should be emphasised in health decisions using criteria of fairness and fundamental principles of ethics correctly understood and chosen in order to solve the real conflicts evident in the distribution of health resources and to enable fair and reasonable distribution of health resources.
ERIC Educational Resources Information Center
Hoff, Erika; Quinn, Jamie M.; Giguere, David
2018-01-01
A close relationship between children's vocabulary size and the grammatical complexity of their speech is well attested but not well understood. The present study used latent change score modeling to examine the dynamic relationships between vocabulary and grammar growth within and across languages in longitudinal data from 90 simultaneous…
How to Create Videos for Extension Education: An Innovative Five-Step Procedure
ERIC Educational Resources Information Center
Dev, Dipti A.; Blitch, Kimberly A.; Hatton-Bowers, Holly; Ramsay, Samantha; Garcia, Aileen S.
2018-01-01
Although the benefits of using video as a learning tool in Extension programs are well known, less is understood about effective methods for creating videos. We present a five-step procedure for developing educational videos that focus on evidence-based practices, and we provide practical examples from our use of the five steps in creating a video…
USDA-ARS?s Scientific Manuscript database
In the mega-diverse insect order Lepidoptera (butterflies and moths; 165,000 species total), 98% of the species fall in the clade Ditrysia, relationships within which are little understood. As the first step in a long-term study of ditrysian phylogeny, we tested the ability of maximum likelihood ana...
Open Practices and Identity: Evidence from Researchers and Educators' Social Media Participation
ERIC Educational Resources Information Center
Veletsianos, George
2013-01-01
The ways that emerging technologies and social media are used and experienced by researchers and educators are poorly understood and inadequately researched. The goal of this study is to examine the online practices of individual scholars in order to explore and understand the activities and practices that they enact when they use social media for…
Reticulate evolution and the human past: an anthropological perspective.
Winder, Isabelle C; Winder, Nick P
2014-01-01
The evidence is mounting that reticulate (web-like) evolution has shaped the biological histories of many macroscopic plants and animals, including non-human primates closely related to Homo sapiens, but the implications of this non-hierarchical evolution for anthropological enquiry are not yet fully understood. When they are understood, the result may be a paradigm shift in evolutionary anthropology. This paper reviews the evidence for reticulated evolution in the non-human primates and human lineage. Then it makes the case for extrapolating this sort of patterning to Homo sapiens and other hominins and explores the implications this would have for research design, method and understandings of evolution in anthropology. Reticulation was significant in human evolutionary history and continues to influence societies today. Anthropologists and human scientists-whether working on ancient or modern populations-thus need to consider the implications of non-hierarchic evolution, particularly where molecular clocks, mathematical models and simplifying assumptions about evolutionary processes are used. This is not just a problem for palaeoanthropology. The simple fact of different mating systems among modern human groups, for example, may demand that more attention is paid to the potential for complexity in human genetic and cultural histories.
Wallace, John L
2012-01-01
The mechanisms underlying the ability of nonsteroidal anti-inflammatory drugs (NSAIDs) to cause ulceration in the stomach and proximal duodenum are well understood, and this injury can largely be prevented through suppression of gastric acid secretion (mainly with proton pump inhibitors). In contrast, the pathogenesis of small intestinal injury induced by NSAIDs is less well understood, involving more complex mechanisms than those in the stomach and proximal duodenum. There is clear evidence for important contributions to NSAID enteropathy of enteric bacteria, bile and enterohepatic recirculation of the NSAID. There is no evidence that suppression of gastric acid secretion will reduce the incidence or severity of NSAID enteropathy. Indeed, clinical data suggest little, if any, benefit. Animal studies suggest a significant exacerbation of NSAID enteropathy when proton pump inhibitors are co-administered with the NSAID. This worsening of damage appears to be linked to changes in the number and types of bacteria in the small intestine during proton pump inhibitor therapy. The distinct mechanisms of NSAID-induced injury in the stomach/proximal duodenum versus the more distal small intestine likely dictate distinct strategies for prevention. © 2011 The Author. British Journal of Pharmacology © 2011 The British Pharmacological Society.
Toward a complete soil C and N cycle: incorporating the soil fauna.
Osler, Graham H R; Sommerkorn, Martin
2007-07-01
Increasing pressures on ecosystems through global climate and other land-use changes require predictive models of their consequences for vital processes such as soil carbon and nitrogen cycling. These environmental changes will undoubtedly affect soil fauna. There is sufficient evidence that soil fauna have significant effects on all of the pools and fluxes in these cycles, and soil fauna mineralize more N than microbes in some habitats. It is therefore essential that their role in the C and N cycle be understood. Here we introduce a new framework that attempts to reconcile our current understanding of the role of soil fauna within the C and N cycle with biogeochemical models and soil food web models. Using a simple stoichiometric approach to integrate our understanding of N mineralization and immobilization with the C:N ratio of substrates and faunal life history characteristics, as used in food web studies, we consider two mechanisms through which soil fauna can directly affect N cycling. First, fauna that are efficient assimilators of C and that have prey with similar C:N ratios as themselves, are likely to contribute directly to the mineral N pool. Second, fauna that are inefficient assimilators of C and that have prey with higher C:N ratios than themselves are likely to contribute most to the dissolved organic matter (DOM) pool. Different groups of fauna are likely to contribute to these two pathways. Protists and bacteria-feeding nematodes are more likely to be important for N mineralization through grazing on microbial biomass, while the effects of enchytraeids and fungal-feeding microarthropods are most likely to be important for DOM production. The model is consistent with experimental evidence and, despite its simplicity, provides a new framework in which the effects of soil fauna on pools and fluxes can be understood. Further, the model highlights our gaps in knowledge, not only for effects of soil fauna on processes, but also for understanding of the soil C and N cycle in general.
The obesity epidemic in children and adults: current evidence and research issues.
Flegal, K M
1999-11-01
The term "epidemic" of obesity implies that obesity is a characteristic of populations, not only of individuals. The purpose of this paper is to review evidence on obesity in populations and to identify future research issues. To examine recent increases in the population prevalence of overweight or obesity, a literature search was undertaken. Trends in overweight or obesity among adults showed considerable variability internationally. Some countries, including Canada, Finland (men), New Zealand, the United Kingdom, the United States, and Western Samoa showed large increases in prevalence (>5 percentage points), whereas several other countries showed smaller or no increases. Overweight is also increasing among children and adolescents, at least in some countries. It is not clear what the expected prevalence of overweight or obesity might be in the current environment, and these findings may be most usefully viewed as shifts in the distribution of a population characteristic. The reasons for these shifts are not clear. The health implications of these shifts are also not clear, in part because trends in cardiovascular risk factors do not always parallel trends in obesity. Of the classic epidemiologic triad of host, agent, and environment, the environment has often received the least attention. The economic, social, and cultural factors that influence the distribution of body mass index in a population are not well understood. Future research needs include continued monitoring of trends in obesity and in related health conditions and observational studies to examine the causes of these trends. Public health research should aim at defining realistic goals and strategies to improve health in an environment conducive to high levels of overweight and obesity.
Chambers, L; Finch, J; Edwards, K; Jeanjean, A; Leigh, R; Gonem, S
2018-03-11
There is evidence that air pollution increases the risk of asthma hospitalizations and healthcare utilization, but the effects on day-to-day asthma control are not fully understood. We undertook a prospective single-centre panel study to test the hypothesis that personal air pollution exposure is associated with asthma symptoms, lung function and airway inflammation. Thirty-two patients with a clinical diagnosis of asthma were provided with a personal air pollution monitor (Cairclip NO 2 /O 3 ) which was kept on or around their person throughout the 12-week follow-up period. Ambient levels of NO 2 and particulate matter were modelled based upon satellite imaging data. Directly measured ozone, NO 2 and particulate matter levels were obtained from a monitoring station in central Leicester. Participants made daily electronic records of asthma symptoms, peak expiratory flow and exhaled nitric oxide. Spirometry and asthma symptom questionnaires were completed at fortnightly study visits. Data were analysed using linear mixed effects models and cross-correlation. Cairclip exposure data were of good quality with clear evidence of diurnal variability and a missing data rate of approximately 20%. We were unable to detect consistent relationships between personal air pollution exposure and clinical outcomes in the group as a whole. In an exploratory subgroup analysis, total oxidant exposure was associated with increased daytime symptoms in women but not men. We did not find compelling evidence that air pollution exposure impacts on day-to-day clinical control in an unselected asthma population, but further studies are required in larger populations with higher exposure levels. Women may be more susceptible than men to the effects of air pollution, an observation which requires confirmation in future studies. © 2018 John Wiley & Sons Ltd.
Seidel, Bastian M; Campbell, Steven; Bell, Erica
2015-03-21
Better understanding of clinical reasoning could reduce diagnostic error linked to 8% of adverse medical events and 30% of malpractice cases. To a greater extent than the evidence-based movement, the clinical reasoning literature asserts the importance of practitioner intuition—unconscious elements of diagnostic reasoning. The study aimed to analyse the content of case report summaries in ways that explored the importance of an evidence concept, not only in relation to research literature but also intuition. The study sample comprised all 789,712 abstracts in English for case reports contained in the database PUBMED for the period 1 January 1983 to 31 December 2012. It was hypothesised that, if evidence and intuition concepts were viewed by these clinical authors as essential to understanding their case reports, they would be more likely to be found in the abstracts. Computational linguistics software was used in 1) concept mapping of 21,631,481 instances of 201 concepts, and 2) specific concept analyses examining 200 paired co-occurrences for 'evidence' and research 'literature' concepts. 'Evidence' is a fundamentally patient-centred, intuitive concept linked to less common concepts about underlying processes, suspected disease mechanisms and diagnostic hunches. In contrast, the use of research literature in clinical reasoning is linked to more common reasoning concepts about specific knowledge and descriptions or presenting features of cases. 'Literature' is by far the most dominant concept, increasing in relevance since 2003, with an overall relevance of 13% versus 5% for 'evidence' which has remained static. The fact that the least present types of reasoning concepts relate to diagnostic hunches to do with underlying processes, such as what is suspected, raises questions about whether intuitive practitioner evidence-making, found in a constellation of dynamic, process concepts, has become less important. The study adds support to the existing corpus of research on clinical reasoning, by suggesting that intuition involves a complex constellation of concepts important to how the construct of evidence is understood. The list of concepts the study generated offers a basis for reflection on the nature of evidence in diagnostic reasoning and the importance of intuition to that reasoning.
Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
Barden, Holly E.; Behnsen, Julia; Bergmann, Uwe; ...
2015-09-14
Solenopora jurassica is a fossil calcareous alga that functioned as an important reef-building organism during the Palaeozoic. It is of significant palaeobiological interest due to its distinctive but poorly understood pink and white banding. Though widely accepted as an alga there is still debate over its taxonomic affinity, with recent work arguing that it should be reclassified as a chaetetid sponge. The banding is thought to be seasonal, but there is no conclusive evidence for this. Other recent work has, however demonstrated the presence of a unique organic boron-containing pink/red pigment in the pink bands of S. jurassica. We presentmore » new geochemical evidence concerning the seasonality and pigmentation of S. jurassica. Seasonal growth cycles are demonstrated by X-ray radiography, which shows differences in calcite density, and by varying δ 13C composition of the bands. Temperature variation in the bands is difficult to constrain accurately due to conflicting patterns arising from Mg/Ca molar ratios and δ 18O data. Fluctuating chlorine levels indicate increased salinity in the white bands, when combined with the isotope data this suggests more suggestive of marine conditions during formation of the white band and a greater freshwater component (lower chlorinity) during pink band precipitation (δ 18O). Increased photosynthesis is inferred within the pink bands in comparison to the white, based on δ 13C. Pyrolysis Gas Chromatography Mass Spectrometry (Py-GCMS) and Fourier Transform Infrared Spectroscopy (FTIR) show the presence of tetramethyl pyrrole, protein moieties and carboxylic acid groups, suggestive of the presence of the red algal pigment phycoerythrin. This is consistent with the pink colour of S. jurassica. As phycoerythrin is only known to occur in algae and cyanobacteria, and no biomarker evidence of bacteria or sponges was detected we conclude S. jurassica is most likely an alga. Pigment analysis may be a reliable classification method for fossil algae.« less
Geochemical Evidence of the Seasonality, Affinity and Pigmenation of Solenopora jurassica
Barden, Holly E.; Behnsen, Julia; Bergmann, Uwe; Leng, Melanie J.; Manning, Phillip L.; Withers, Philip J.; Wogelius, Roy A.; van Dongen, Bart E.
2015-01-01
Solenopora jurassica is a fossil calcareous alga that functioned as an important reef-building organism during the Palaeozoic. It is of significant palaeobiological interest due to its distinctive but poorly understood pink and white banding. Though widely accepted as an alga there is still debate over its taxonomic affinity, with recent work arguing that it should be reclassified as a chaetetid sponge. The banding is thought to be seasonal, but there is no conclusive evidence for this. Other recent work has, however demonstrated the presence of a unique organic boron-containing pink/red pigment in the pink bands of S. jurassica. We present new geochemical evidence concerning the seasonality and pigmentation of S. jurassica. Seasonal growth cycles are demonstrated by X-ray radiography, which shows differences in calcite density, and by varying δ13C composition of the bands. Temperature variation in the bands is difficult to constrain accurately due to conflicting patterns arising from Mg/Ca molar ratios and δ18O data. Fluctuating chlorine levels indicate increased salinity in the white bands, when combined with the isotope data this suggests more suggestive of marine conditions during formation of the white band and a greater freshwater component (lower chlorinity) during pink band precipitation (δ18O). Increased photosynthesis is inferred within the pink bands in comparison to the white, based on δ13C. Pyrolysis Gas Chromatography Mass Spectrometry (Py-GCMS) and Fourier Transform Infrared Spectroscopy (FTIR) show the presence of tetramethyl pyrrole, protein moieties and carboxylic acid groups, suggestive of the presence of the red algal pigment phycoerythrin. This is consistent with the pink colour of S. jurassica. As phycoerythrin is only known to occur in algae and cyanobacteria, and no biomarker evidence of bacteria or sponges was detected we conclude S. jurassica is most likely an alga. Pigment analysis may be a reliable classification method for fossil algae. PMID:26367117
Schwarz, Frank; Derks, Jan; Monje, Alberto; Wang, Hom-Lay
2018-06-01
This narrative review provides an evidence-based overview on peri-implantitis for the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions. A literature review was conducted addressing the following topics: 1) definition of peri-implantitis; 2) conversion from peri-implant mucositis to peri-implantitis, 3) onset and pattern of disease progression, 4) characteristics of peri-implantitis, 5) risk factors/indicators for peri-implantitis, and 6) progressive crestal bone loss in the absence of soft tissue inflammation. 1)Peri-implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant connective tissue and progressive loss of supporting bone. 2)The histopathologic and clinical conditions leading to the conversion from peri-implant mucositis to peri-implantitis are not completely understood. 3)The onset of peri-implantitis may occur early during follow-up and the disease progresses in a non-linear and accelerating pattern. 4a)Peri-implantitis sites exhibit clinical signs of inflammation and increased probing depths compared to baseline measurements. 4b)At the histologic level, compared to periodontitis sites, peri-implantitis sites often have larger inflammatory lesions. 4c)Surgical entry at peri-implantitis sites often reveals a circumferential pattern of bone loss. 5a)There is strong evidence that there is an increased risk of developing peri-implantitis in patients who have a history of chronic periodontitis, poor plaque control skills, and no regular maintenance care after implant therapy. Data identifying "smoking" and "diabetes" as potential risk factors/indicators for peri-implantitis are inconclusive. 5b)There is some limited evidence linking peri-implantitis to other factors such as: post-restorative presence of submucosal cement, lack of peri-implant keratinized mucosa and positioning of implants that make it difficult to perform oral hygiene and maintenance. 6)Evidence suggests that progressive crestal bone loss around implants in the absence of clinical signs of soft tissue inflammation is a rare event. © 2018 American Academy of Periodontology and European Federation of Periodontology.
The association between diet quality, dietary patterns and depression in adults: a systematic review
2013-01-01
Background Recent evidence suggests that diet modifies key biological factors associated with the development of depression; however, associations between diet quality and depression are not fully understood. We performed a systematic review to evaluate existing evidence regarding the association between diet quality and depression. Method A computer-aided literature search was conducted using Medline, CINAHL, and PsycINFO, January 1965 to October 2011, and a best-evidence analysis performed. Results Twenty-five studies from nine countries met eligibility criteria. Our best-evidence analyses found limited evidence to support an association between traditional diets (Mediterranean or Norwegian diets) and depression. We also observed a conflicting level of evidence for associations between (i) a traditional Japanese diet and depression, (ii) a “healthy” diet and depression, (iii) a Western diet and depression, and (iv) individuals with depression and the likelihood of eating a less healthy diet. Conclusion To our knowledge, this is the first review to synthesize and critically analyze evidence regarding diet quality, dietary patterns and depression. Further studies are urgently required to elucidate whether a true causal association exists. PMID:23802679
Oei, Adam C; Patterson, Michael D
2015-01-01
Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well-understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for 20 h. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat) with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch) with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis.
Distinct Contributions of T1R2 and T1R3 Taste Receptor Subunits to the Detection of Sweet Stimuli
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nie,Y.; Vigues, S.; Hobbs, J.
2005-01-01
The molecular mechanisms by which G protein-coupled receptor (GPCR)-type chemosensory receptors of animals selectively interact with their cognate ligands remain poorly understood. There is growing evidence that many chemosensory receptors exist in multimeric complexes, though little is known about the relative contributions of individual subunits to receptor functions. This study showed that each of the two subunits in the mammalian heteromeric T1R2:T1R3 sweet taste receptor binds sweet stimuli, though with distinct affinities and conformational changes. Furthermore, ligand affinities for T1R3 are drastically reduced by the introduction of a single amino acid change associated with decreased sweet taste sensitivity in mice.more » Thus, individual T1R subunits increase the receptive range of the sweet taste receptor, offering a functional mechanism for phenotypic variations in sweet taste.« less
Leadership, Burnout, and Job Satisfaction in Outpatient Drug-Free Treatment Programs
Broome, Kirk M.; Knight, Danica K.; Edwards, Jennifer R.; Flynn, Patrick M.
2009-01-01
Counselors are a critical component of substance abuse treatment programming, but their working experiences are not yet well understood. As treatment-improvement efforts focus increasingly on these individuals, their perceptions of program leadership, emotional burnout, and job satisfaction and related attitudes take on greater significance. This study explores counselor views and the impact of organizational context using data from a nationwide set of 94 outpatient drug-free (ODF) treatment programs in a hierarchical linear model (HLM) analysis. Results show counselors hold generally positive opinions of program director leadership and job satisfaction, and have low levels of burnout, but they also have important variations in their ratings. Higher counselor caseloads were related to poorer ratings, and leadership behaviors predicted both satisfaction and burnout. These findings add further evidence that treatment providers should also address the workplace environment for staff as part of quality-improvement efforts. PMID:19339143
HIV-1, Reactive Oxygen Species and Vascular Complications
Porter, Kristi M.; Sutliff, Roy L.
2012-01-01
Over 1 million people in the United States and 33 million individuals worldwide suffer from HIV/AIDS. Since its discovery, HIV/AIDS has been associated with an increased susceptibility to opportunistic infection due to immune dysfunction. Highly active antiretroviral therapies (HAART) restore immune function and, as a result, people infected with HIV-1 are living longer. This improved survival of HIV-1 patients has revealed a previously unrecognized risk of developing vascular complications, such as atherosclerosis and pulmonary hypertension. The mechanisms underlying these HIV-associated vascular disorders are poorly understood. However, HIV-induced elevations in reactive oxygen species, including superoxide and hydrogen peroxide, may contribute to vascular disease development and progression by altering cell function and redox-sensitive signaling pathways. In this review, we summarize the clinical and experimental evidence demonstrating HIV- and HIV antiretroviral therapy-induced alterations in reactive oxygen species (ROS) and how these effects likely contribute to vascular dysfunction and disease. PMID:22564529
Lorch, Jeffrey M.; Lankton, Julia S.; Werner, Katrien; Falendysz, Elizabeth A.; McCurley, Kevin; Blehert, David S.
2015-01-01
IMPORTANCE Skin infections in snakes, referred to as snake fungal disease (SFD), have been reported with increasing frequency in wild snakes in the eastern United States. While most of these infections are associated with the fungusOphidiomyces ophiodiicola, there has been no conclusive evidence to implicate this fungus as a primary pathogen. Furthermore, it is not understood why the infections affect different host populations differently. Our experiment demonstrates that O. ophiodiicola is the causative agent of SFD and can elicit pathological changes that likely impact fitness of wild snakes. This information, and the laboratory model we describe, will be essential in addressing unresolved questions regarding disease ecology and outcomes of O. ophiodiicola infection and helping to conserve snake populations threatened by the disease. The SFD model of infection also offers utility for exploring larger concepts related to comparative fungal virulence, host response, and host-pathogen evolution.
Inflammation: The Common Pathway of Stress-Related Diseases
Liu, Yun-Zi; Wang, Yun-Xia; Jiang, Chun-Lei
2017-01-01
While modernization has dramatically increased lifespan, it has also witnessed that the nature of stress has changed dramatically. Chronic stress result failures of homeostasis thus lead to various diseases such as atherosclerosis, non-alcoholic fatty liver disease (NAFLD) and depression. However, while 75%–90% of human diseases is related to the activation of stress system, the common pathways between stress exposure and pathophysiological processes underlying disease is still debatable. Chronic inflammation is an essential component of chronic diseases. Additionally, accumulating evidence suggested that excessive inflammation plays critical roles in the pathophysiology of the stress-related diseases, yet the basis for this connection is not fully understood. Here we discuss the role of inflammation in stress-induced diseases and suggest a common pathway for stress-related diseases that is based on chronic mild inflammation. This framework highlights the fundamental impact of inflammation mechanisms and provides a new perspective on the prevention and treatment of stress-related diseases. PMID:28676747
The Migraine-Ischemic Stroke Relation in Young Adults
Pezzini, Alessandro; Del Zotto, Elisabetta; Giossi, Alessia; Volonghi, Irene; Costa, Paolo; Dalla Volta, Giorgio; Padovani, Alessandro
2011-01-01
In spite of the strong epidemiologic evidence linking migraine and ischemic stroke in young adults, the mechanisms explaining this association remain poorly understood. The observation that stroke occurs more frequently during the interictal phase of migraine prompts to speculation that an indirect relation between the two diseases might exist. In this regard, four major issues might be considered which may be summarized as follows: (1) the migraine-ischemic stroke relation is influenced by specific risk factors such as patent foramen ovale or endothelial dysfunction and more frequent in particular conditions like spontaneous cervical artery dissection; (2) migraine is associated with an increased prevalence of cardiovascular risk factors; (3) the link is caused by migraine-specific drugs; (4) migraine and ischemic vascular events are linked via a genetic component. In the present paper, we will review epidemiological studies, discuss potential mechanisms of migraine-induced stroke and comorbid ischemic stroke, and pose new research questions. PMID:21197470
Fire risk in San Diego County, California: A weighted Bayesian model approach
Kolden, Crystal A.; Weigel, Timothy J.
2007-01-01
Fire risk models are widely utilized to mitigate wildfire hazards, but models are often based on expert opinions of less understood fire-ignition and spread processes. In this study, we used an empirically derived weights-of-evidence model to assess what factors produce fire ignitions east of San Diego, California. We created and validated a dynamic model of fire-ignition risk based on land characteristics and existing fire-ignition history data, and predicted ignition risk for a future urbanization scenario. We then combined our empirical ignition-risk model with a fuzzy fire behavior-risk model developed by wildfire experts to create a hybrid model of overall fire risk. We found that roads influence fire ignitions and that future growth will increase risk in new rural development areas. We conclude that empirically derived risk models and hybrid models offer an alternative method to assess current and future fire risk based on management actions.
Heterochromatin-Encoded Satellite RNAs Induce Breast Cancer.
Zhu, Quan; Hoong, Nien; Aslanian, Aaron; Hara, Toshiro; Benner, Christopher; Heinz, Sven; Miga, Karen H; Ke, Eugene; Verma, Sachin; Soroczynski, Jan; Yates, John R; Hunter, Tony; Verma, Inder M
2018-06-07
Heterochromatic repetitive satellite RNAs are extensively transcribed in a variety of human cancers, including BRCA1 mutant breast cancer. Aberrant expression of satellite RNAs in cultured cells induces the DNA damage response, activates cell cycle checkpoints, and causes defects in chromosome segregation. However, the mechanism by which satellite RNA expression leads to genomic instability is not well understood. Here we provide evidence that increased levels of satellite RNAs in mammary glands induce tumor formation in mice. Using mass spectrometry, we further show that genomic instability induced by satellite RNAs occurs through interactions with BRCA1-associated protein networks required for the stabilization of DNA replication forks. Additionally, de-stabilized replication forks likely promote the formation of RNA-DNA hybrids in cells expressing satellite RNAs. These studies lay the foundation for developing novel therapeutic strategies that block the effects of non-coding satellite RNAs in cancer cells. Copyright © 2018 Elsevier Inc. All rights reserved.
Qi, Heqiang; Lu, Yuyan; Lv, Jie; Wu, Huita; Lu, Jing; Zhang, Changmao; Zhang, Sheng; Bao, Qing; Zhang, Xiuming; Xie, Chengrong; Yin, Zhenyu
2018-05-18
Hepatocellular carcinoma (HCC) accounts for a large proportion of cancer-associated mortality worldwide. The functional impact of long noncoding RNAs (lncRNAs) in human cancer is not fully understood. Here, we identified a novel oncogenic lncRNA termed lncPARP1, which was significantly upregulated in HCC. Increase of lncPARP1 expression was associated with age, AFP levels, tumor size, recurrence, and poor prognosis of HCC patients. Loss-of-function approaches showed that knockdown of lncPARP1 inhibited proliferation, migration and invasion, while induced apoptosis in HCC cells. Moreover, mechanistic investigation demonstrated that PARP1 was an underlying target of lncPARP1 in HCC. In summary, we provide the first evidence that lncPARP1 exerts an oncogene to promote HCC development and progression, at least in part, by affecting PARP1 expression. ©2018 The Author(s).
From Embryonic Development to Human Diseases: The Functional Role of Caveolae/Caveolin
Sohn, Jihee; Brick, Rachel M.; Tuan, Rocky S.
2017-01-01
Caveolae, an almost ubiquitous, structural component of the plasma membrane, play a critical role in many functions essential for proper cell function, including membrane trafficking, signal transduction, extracellular matrix remodeling, and tissue regeneration. Three main types of caveolin proteins have been identified from caveolae since the discovery of caveolin-1 in the early 1990s. All three (Cav-1, Cav-2, and Cav-3) play crucial roles in mammalian physiology, and can effect pathogenesis in a wide range of human diseases. While many biological activities of caveolins have been uncovered since its discovery, their role and regulation in embryonic develop remain largely poorly understood, although there is increasing evidence that caveolins may be linked to lung and brain birth defects. Further investigations are clearly needed to decipher how caveolae/caveolins mediate cellular functions and activities of normal embryogenesis and how their perturbations contribute to developmental disorders. PMID:26991990
Cuadrado, Cristóbal; Zitko, Pedro; Covarrubias, Trinidad; Hernandez, Dunia; Sade, Cristina; Klein, Carolina; Gomez, Alejandro
2015-01-01
Adolescent suicide rates (ASR) are a matter of concern worldwide. Causes of this trend are not understood and could correspond to socioeconomic factors such as inequality. To investigate sociodemographic variables related to ASR, particularly the potential association with indicators of socioeconomic inequality. Cross-sectional ecological study analyzing data from 29 health districts with univariate and multivariable multilevel Poisson models. ASR were higher in male adolescents and at increasing age. No association was found between ASR and inequality (Gini coefficient and 20/20 ratio). Analysis revealed that living in a single-parent family is associated with ASR. The usual demographic patterns of adolescent suicide apply in Chile. An emerging variable of interest is single-parent family. No cross-sectional association between social inequality and ASR was found based on conflicting evidence. These results should be explored in future prospective population studies to further understand associated social factors.
Lavender, Jason M; Brown, Tiffany A; Murray, Stuart B
2017-06-01
There is growing recognition that eating disorder (ED) symptoms, particularly those of a muscularity-oriented nature, are more common in men than previously understood. The purpose of the current review is to describe contemporary directions and implications of research on traditional and muscularity-oriented ED symptoms among males. Evidence indicates that ED symptoms occur in a substantial minority of men. Importantly, recent research has focused on muscularity-oriented body image and disordered eating in males, demonstrating the prevalence, correlates, and consequences of maladaptive muscularity-oriented attitudes and behaviors. A growing number of assessments are available to measure these constructs in males, and preliminary treatment considerations have begun to be addressed in the literature. Research on male EDs and body image is increasingly focusing on muscularity-oriented manifestations. Continued empirical work will be critical to improve our understanding of the onset, maintenance, and treatment of muscularity-oriented disordered eating in males.
Downey, Luke A.; Loftis, Jennifer M.
2014-01-01
Central nervous system (CNS) damage associated with psychostimulant dependence may be an ongoing, degenerative process with adverse effects on neuropsychiatric function. However, the molecular mechanisms regarding how altered energy regulation affects immune response in the context of substance use disorders are not fully understood. This review summarizes the current evidence regarding the effects of psychostimulant [particularly 3,4-methylenedioxy-N-methylamphetamine (MDMA) and methamphetamine] exposure on brain energy regulation, immune response, and neuropsychiatric function. Importantly, the neuropsychiatric impairments (e.g., cognitive deficits, depression, and anxiety) that persist following abstinence are associated with poorer treatment outcomes – increased relapse rates, lower treatment retention rates, and reduced daily functioning. Qualifying the molecular changes within the CNS according to the exposure and use patterns of specifically abused substances should inform the development of new therapeutic approaches for addiction treatment. PMID:24485894
Hamperl, Stephan; Cimprich, Karlene A.
2014-01-01
Accurate DNA replication and DNA repair are crucial for the maintenance of genome stability, and it is generally accepted that failure of these processes is a major source of DNA damage in cells. Intriguingly, recent evidence suggests that DNA damage is more likely to occur at genomic loci with high transcriptional activity. Furthermore, loss of certain RNA processing factors in eukaryotic cells is associated with increased formation of co-transcriptional RNA:DNA hybrid structures known as R-loops, resulting in double-strand breaks (DSBs) and DNA damage. However, the molecular mechanisms by which R-loop structures ultimately lead to DNA breaks and genome instability is not well understood. In this review, we summarize the current knowledge about the formation, recognition and processing of RNA:DNA hybrids, and discuss possible mechanisms by which these structures contribute to DNA damage and genome instability in the cell. PMID:24746923
Boschen, K E; Keller, S M; Roth, T L; Klintsova, A Y
The long-term effects of developmental alcohol and stress exposure are well documented in both humans and non-human animal models. Damage to the brain and attendant life-long impairments in cognition and increased risk for psychiatric disorders are debilitating consequences of developmental exposure to alcohol and/or psychological stress. Here we discuss evidence for a role of epigenetic mechanisms in mediating these consequences. While we highlight some of the common ways in which stress or alcohol impact the epigenome, we point out that little is understood of the epigenome's response to experiencing both stress and alcohol exposure, though stress is a contributing factor as to why women drink during pregnancy. Advancing our understanding of this relationship is of critical concern not just for the health and well-being of individuals directly exposed to these teratogens, but for generations to come. Copyright © 2018 Elsevier Inc. All rights reserved.
Darido, Charbel; Georgy, Smitha R; Wilanowski, Tomasz; Dworkin, Sebastian; Auden, Alana; Zhao, Quan; Rank, Gerhard; Srivastava, Seema; Finlay, Moira J; Papenfuss, Anthony T; Pandolfi, Pier Paolo; Pearson, Richard B; Jane, Stephen M
2011-11-15
Despite its prevalence, the molecular basis of squamous cell carcinoma (SCC) remains poorly understood. Here, we identify the developmental transcription factor Grhl3 as a potent tumor suppressor of SCC in mice, and demonstrate that targeting of Grhl3 by a miR-21-dependent proto-oncogenic network underpins SCC in humans. Deletion of Grhl3 in adult epidermis evokes loss of expression of PTEN, a direct GRHL3 target, resulting in aggressive SCC induced by activation of PI3K/AKT/mTOR signaling. Restoration of Pten expression completely abrogates SCC formation. Reduced levels of GRHL3 and PTEN are evident in human skin, and head and neck SCC, associated with increased expression of miR-21, which targets both tumor suppressors. Our data define the GRHL3-PTEN axis as a critical tumor suppressor pathway in SCC. 2011 Elsevier Inc. All rights reserved.
[Myofibroblasts and afferent signalling in the urinary bladder. A concept].
Neuhaus, J; Scholler, U; Freick, K; Schwalenberg, T; Heinrich, M; Horn, L C; Stolzenburg, J U
2008-09-01
Afferent signal transduction in the urinary bladder is still not clearly understood. An increasing body of evidence supports the view of complex interactions between urothelium, suburothelial myofibroblasts, and sensory nerves. Bladder tissue from tumour patients was used in this study. Methods included confocal immunofluorescence, polymerase chain reaction, calcium imaging, and fluorescence recovery after photobleaching (FRAP).Myofibroblasts express muscarinic and purinergic receptors. They show constitutive spontaneous activity in calcium imaging, which completely depends on extracellular calcium. Stimulation with carbachol and ATP-evoked intracellular calcium transients also depend on extracellular calcium. The intensive coupling between the cells is significantly diminished by incubation with TGF-beta 1. Myofibroblasts form an important cellular element within the afferent signalling of the urinary bladder. They possess all features required to take part in the complex interactions with urothelial cells and sensory nerves. Modulation of their function by cytokines may provide a pathomechanism for bladder dysfunction.
Exploring fractal behaviour of blood oxygen saturation in preterm babies
NASA Astrophysics Data System (ADS)
Zahari, Marina; Hui, Tan Xin; Zainuri, Nuryazmin Ahmat; Darlow, Brian A.
2017-04-01
Recent evidence has been emerging that oxygenation instability in preterm babies could lead to an increased risk of retinal injury such as retinopathy of prematurity. There is a potential that disease severity could be better understood using nonlinear methods for time series data such as fractal theories [1]. Theories on fractal behaviours have been employed by researchers in various disciplines who were motivated to look into the behaviour or structure of irregular fluctuations in temporal data. In this study, an investigation was carried out to examine whether fractal behaviour could be detected in blood oxygen time series. Detection for the presence of fractals in oxygen data of preterm infants was performed using the methods of power spectrum, empirical probability distribution function and autocorrelation function. The results from these fractal identification methods indicate the possibility that these data exhibit fractal nature. Subsequently, a fractal framework for future research was suggested for oxygen time series.
Low calorie sweeteners: Evidence remains lacking for effects on human gut function.
Bryant, Charlotte; Mclaughlin, John
2016-10-01
The importance of nutrient induced gut-brain signalling in the regulation of human food intake has become an increasing focus of research. Much of the caloric excess consumed comes from dietary sugars, but our knowledge about the mechanisms mediating the physiological and appetitive effects of sweet tastants in the human gut and gut-brain axis is far from complete. The comparative effects of natural sugars vs low calorie sweeteners are also poorly understood. Research in animal and cellular models has suggested a key functional role in gut endocrine cells for the sweet taste receptors previously well described in oral taste. However human studies to date have very consistently failed to show that activation of the sweet taste receptor by low calorie sweeteners placed in the human gut fails to replicate any of the effects on gastric motility, gut hormones or appetitive responses evoked by caloric sugars. Copyright © 2016. Published by Elsevier Inc.
Influence of the local environment on Mn acceptors in GaAs
NASA Astrophysics Data System (ADS)
Lee, Donghun; Gohlke, David; Benjamin, Anne; Gupta, Jay A.
2015-04-01
As transistors continue to shrink toward nanoscale dimensions, their characteristics are increasingly dependent on the statistical variations of impurities in the semiconductor material. The scanning tunneling microscope (STM) can be used to not only study prototype devices with atomically precise placement of impurity atoms, but can also probe how the properties of these impurities depend on the local environment. Tunneling spectroscopy of Mn acceptors in GaAs indicates that surface-layer Mn act as a deep acceptor, with a hole binding energy that can be tuned by positioning charged defects nearby. Band bending induced by the tip or by these defects can also tune the ionization state of the acceptor complex, evident as a ring-like contrast in STM images. The interplay of these effects is explored over a wide range of defect distances, and understood using iterative simulations of tip-induced band bending.
Leadership, burnout, and job satisfaction in outpatient drug-free treatment programs.
Broome, Kirk M; Knight, Danica K; Edwards, Jennifer R; Flynn, Patrick M
2009-09-01
Counselors are a critical component of substance abuse treatment programming, but their working experiences are not yet well understood. As treatment improvement efforts focus increasingly on these individuals, their perceptions of program leadership, emotional burnout, and job satisfaction and related attitudes take on greater significance. This study explores counselor views and the impact of organizational context using data from a nationwide set of 94 outpatient drug-free treatment programs in a hierarchical linear model analysis. Results show counselors hold generally positive opinions of program director leadership and job satisfaction and have low levels of burnout, but they also have important variations in their ratings. Higher counselor caseloads were related to poorer ratings, and leadership behaviors predicted both satisfaction and burnout. These findings add further evidence that treatment providers should also address the workplace environment for staff as part of quality improvement efforts.
Micrometastases in neuroblastoma: are they clinically important?
Burchill, S A
2004-01-01
Despite advances in the treatment of neuroblastoma (NBL), recurrence and metastases continue to pose major problems in clinical management. The relation between micrometastases and the development of secondary disease is not fully understood. However, accurate methods to detect low numbers of tumour cells may allow the evaluation of their role in the disease process, and by implication the possible benefits of eliminating them. Although there is substantial evidence for the increased sensitivity of current molecular methods for the detection of NBL cells compared with more conventional cytology, the clinical relevance and usefulness of detecting this disease remain controversial. The primary goal of current translational research must be to evaluate the clinical relevance of micrometastatic disease detected by these methods in multicentre prospective clinical outcome studies. Only then can the clinical usefulness of these methods be defined so that they may be introduced into relevant clinical practice. PMID:14693828
PINK1 deficiency enhances autophagy and mitophagy induction.
Gómez-Sánchez, Rubén; Yakhine-Diop, Sokhna M S; Bravo-San Pedro, José M; Pizarro-Estrella, Elisa; Rodríguez-Arribas, Mario; Climent, Vicente; Martin-Cano, Francisco E; González-Soltero, María E; Tandon, Anurag; Fuentes, José M; González-Polo, Rosa A
2016-03-01
Parkinson's disease (PD) is a neurodegenerative disorder with poorly understood etiology. Increasing evidence suggests that age-dependent compromise of the maintenance of mitochondrial function is a key risk factor. Several proteins encoded by PD-related genes are associated with mitochondria including PTEN-induced putative kinase 1 (PINK1), which was first identified as a gene that is upregulated by PTEN. Loss-of-function PINK1 mutations induce mitochondrial dysfunction and, ultimately, neuronal cell death. To mitigate the negative effects of altered cellular functions cells possess a degradation mechanism called autophagy for recycling damaged components; selective elimination of dysfunctional mitochondria by autophagy is termed mitophagy. Our study indicates that autophagy and mitophagy are upregulated in PINK1-deficient cells, and is the first report to demonstrate efficient fluxes by one-step analysis. We propose that autophagy is induced to maintain cellular homeostasis under conditions of non-regulated mitochondrial quality control.
PINK1 deficiency enhances autophagy and mitophagy induction
Gómez-Sánchez, Rubén; Yakhine-Diop, Sokhna M S; Bravo-San Pedro, José M; Pizarro-Estrella, Elisa; Rodríguez-Arribas, Mario; Climent, Vicente; Martin-Cano, Francisco E; González-Soltero, María E; Tandon, Anurag; Fuentes, José M; González-Polo, Rosa A
2016-01-01
Parkinson's disease (PD) is a neurodegenerative disorder with poorly understood etiology. Increasing evidence suggests that age-dependent compromise of the maintenance of mitochondrial function is a key risk factor. Several proteins encoded by PD-related genes are associated with mitochondria including PTEN-induced putative kinase 1 (PINK1), which was first identified as a gene that is upregulated by PTEN. Loss-of-function PINK1 mutations induce mitochondrial dysfunction and, ultimately, neuronal cell death. To mitigate the negative effects of altered cellular functions cells possess a degradation mechanism called autophagy for recycling damaged components; selective elimination of dysfunctional mitochondria by autophagy is termed mitophagy. Our study indicates that autophagy and mitophagy are upregulated in PINK1-deficient cells, and is the first report to demonstrate efficient fluxes by one-step analysis. We propose that autophagy is induced to maintain cellular homeostasis under conditions of non-regulated mitochondrial quality control. PMID:27308585
Is depression an inflammatory condition? A review of available evidence.
Hashmi, Ali Madeeh; Butt, Zeeshan; Umair, Muhammad
2013-07-01
The current review examines the relationship between depression and the inflammatory immune response. Mood disorders are a significant cause of morbidity and the etiology of depression is still not clearly understood. Many studies have shown links between inflammatory cytokines and mood disorders, including elevated level of cytokines like tumour necrosis factor-alpha (TNF alpha), Interleukins (IL-1,IL-6) and others. Raised levels of cytokines have been shown to increase depressive behaviour in animal models, while many anti-depressants reverse this behaviour alongside reducing the Central Nervous System (CNS) inflammatory response and reduction in the amounts of inflammatory cytokines. Cytokines reduce neurogenesis, Brain Derived Neurotrophic Factor (BDNF) and neuronal plasticity in the CNS, while many anti-depressants have been shown to reverse these processes. The considerations of anti-depressants as anti-inflammatory agents, and implication of other anti-inflammatory therapeutics for the treatment of depression are pointed out.
The co-production of what? Knowledge, values, and social relations in health care.
Filipe, Angela; Renedo, Alicia; Marston, Cicely
2017-05-01
"Co-production" is becoming an increasingly popular term in policymaking, governance, and research. While the shift from engagement and involvement to co-production in health care holds the promise of revolutionising health services and research, it is not always evident what counts as co-production: what is being produced, under what circumstances, and with what implications for participants. We discuss these questions and propose that co-production can be understood as an exploratory space and a generative process that leads to different, and sometimes unexpected, forms of knowledge, values, and social relations. By opening up this discussion, we hope to stimulate future debates on co-production as well as draw out ways of thinking differently about collaboration and participation in health care and research. Part of the title of this article is inspired by the book "The Social Construction of What?" by Ian Hacking (Cambridge, MA: Harvard University Press; 2000).
Downey, Luke A; Loftis, Jennifer M
2014-03-15
Central nervous system (CNS) damage associated with psychostimulant dependence may be an ongoing, degenerative process with adverse effects on neuropsychiatric function. However, the molecular mechanisms regarding how altered energy regulation affects immune response in the context of substance use disorders are not fully understood. This review summarizes the current evidence regarding the effects of psychostimulant [particularly 3,4-methylenedioxy-N-methylamphetamine (MDMA) and methamphetamine] exposure on brain energy regulation, immune response, and neuropsychiatric function. Importantly, the neuropsychiatric impairments (e.g., cognitive deficits, depression, and anxiety) that persist following abstinence are associated with poorer treatment outcomes - increased relapse rates, lower treatment retention rates, and reduced daily functioning. Qualifying the molecular changes within the CNS according to the exposure and use patterns of specifically abused substances should inform the development of new therapeutic approaches for addiction treatment. Published by Elsevier B.V.
Kruppel-like factor 2 (KLF2) regulates proinflammatory activation of monocytes
Das, Hiranmoy; Kumar, Ajay; Lin, Zhiyong; Patino, Willmar D.; Hwang, Paul M.; Feinberg, Mark W.; Majumder, Pradip K.; Jain, Mukesh K.
2006-01-01
The mechanisms regulating activation of monocytes remain incompletely understood. Herein we provide evidence that Kruppel-like factor 2 (KLF2) inhibits proinflammatory activation of monocytes. In vitro, KLF2 expression in monocytes is reduced by cytokine activation or differentiation. Consistent with this observation, KLF2 expression in circulating monocytes is reduced in patients with chronic inflammatory conditions such as coronary artery disease. Adenoviral overexpression of KLF2 inhibits the LPS-mediated induction of proinflammatory factors, cytokines, and chemokines and reduces phagocytosis. Conversely, short interfering RNA-mediated reduction in KLF2 increased inflammatory gene expression. Reconstitution of immunodeficient mice with KLF2-overexpressing monocytes significantly reduced carrageenan-induced acute paw edema formation. Mechanistically, KLF2 inhibits the transcriptional activity of both NF-κB and activator protein 1, in part by means of recruitment of transcriptional coactivator p300/CBP-associated factor. These observations identify KLF2 as a novel negative regulator of monocytic activation. PMID:16617118
Oei, Adam C.; Patterson, Michael D.
2015-01-01
Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well-understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for 20 h. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat) with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch) with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis. PMID:25713551
Recent Advances in Molecular Mechanisms of Abdominal Aortic Aneurysm Formation
Annambhotla, Suman; Bourgeois, Sebastian; Wang, Xinwen; Lin, Peter H.; Yao, Qizhi; Chen, Changyi
2010-01-01
Abdominal Aortic Aneurysm (AAA) is an increasingly common clinical condition with fatal implications. It is associated with advanced age, male gender, cigarette smoking, atherosclerosis, hypertension, and genetic predisposition. Although significant evidence has emerged in the last decade, the molecular mechanisms of AAA formation remains poorly understood. Currently, the treatment for AAA remains primarily surgical with the lone innovation of endovascular therapy. With advance in the human genome, understanding precisely which molecules and genes mediate AAA development and blocking their activity at the molecular level could lead to important new discoveries and therapies. This review summarizes recent updates in molecular mechanisms of AAA formation including animal models, autoimmune components, infection, key molecules and cytokines, mechanical forces, genetics and pharmacotherapy. This review will be helpful to those who want to recognize the newest endeavors within the field and identify possible lines of investigation in AAA. PMID:18259804
Sperm competition risk drives rapid ejaculate adjustments mediated by seminal fluid
Steeves, Tammy E; Gemmell, Neil J; Rosengrave, Patrice C
2017-01-01
In many species, males can make rapid adjustments to ejaculate performance in response to sperm competition risk; however, the mechanisms behind these changes are not understood. Here, we manipulate male social status in an externally fertilising fish, chinook salmon (Oncorhynchus tshawytscha), and find that in less than 48 hr, males can upregulate sperm velocity when faced with an increased risk of sperm competition. Using a series of in vitro sperm manipulation and competition experiments, we show that rapid changes in sperm velocity are mediated by seminal fluid and the effect of seminal fluid on sperm velocity directly impacts paternity share and therefore reproductive success. These combined findings, completely consistent with sperm competition theory, provide unequivocal evidence that sperm competition risk drives plastic adjustment of ejaculate quality, that seminal fluid harbours the mechanism for the rapid adjustment of sperm velocity and that fitness benefits accrue to males from such adjustment. PMID:29084621
Sperm competition risk drives rapid ejaculate adjustments mediated by seminal fluid.
Bartlett, Michael J; Steeves, Tammy E; Gemmell, Neil J; Rosengrave, Patrice C
2017-10-31
In many species, males can make rapid adjustments to ejaculate performance in response to sperm competition risk; however, the mechanisms behind these changes are not understood. Here, we manipulate male social status in an externally fertilising fish, chinook salmon ( Oncorhynchus tshawytscha ), and find that in less than 48 hr, males can upregulate sperm velocity when faced with an increased risk of sperm competition. Using a series of in vitro sperm manipulation and competition experiments, we show that rapid changes in sperm velocity are mediated by seminal fluid and the effect of seminal fluid on sperm velocity directly impacts paternity share and therefore reproductive success. These combined findings, completely consistent with sperm competition theory, provide unequivocal evidence that sperm competition risk drives plastic adjustment of ejaculate quality, that seminal fluid harbours the mechanism for the rapid adjustment of sperm velocity and that fitness benefits accrue to males from such adjustment.
Treatment of type 2 diabetes mellitus in elderly patients.
Gómez-Huelgas, R; Gómez Peralta, F; Rodríguez Mañas, L; Formiga, F; Puig Domingo, M; Mediavilla Bravo, J J; Miranda, C; Ena, J
2018-03-01
The prevalence of type 2 diabetes mellitus (DM2) increases markedly with age. Antidiabetic treatment and the objectives of glycaemic control in elderly patients with DM2 should be individualised according to their biopsychosocial characteristics. In elderly patients for whom the benefits of intensive antidiabetic treatment are limited, the basic objectives should be to improve the quality of life, preserve functionality and avoid adverse effects, especially hypoglycaemia. Treatment of DM2 in the elderly was the subject of a consensus document published in 2012 and endorsed by several Spanish scientific societies. Since then, new therapeutic groups and evidence have emerged that warrant an update to this consensus document. The present document focuses on the therapeutic aspects of DM2 in elderly patients, understood as being older than 75 years or frail. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.
[Treatment of type 2 diabetes mellitus in elderly patients].
Gómez-Huelgas, R; Gómez Peralta, F; Rodríguez Mañas, L; Formiga, F; Puig Domingo, M; Mediavilla Bravo, J J; Miranda, C; Ena, J
The prevalence of type 2 diabetes mellitus (DM2) increases markedly with age. Antidiabetic treatment and the objectives of glycaemic control in elderly patients with DM2 should be individualised according to their biopsychosocial characteristics. In elderly patients for whom the benefits of intensive antidiabetic treatment are limited, the basic objectives should be to improve the quality of life, preserve functionality and avoid adverse effects, especially hypoglycaemia. Treatment of DM2 in the elderly was the subject of a consensus document published in 2012 and endorsed by several Spanish scientific societies. Since then, new therapeutic groups and evidence have emerged that warrant an update to this consensus document. The present document focuses on the therapeutic aspects of DM2 in elderly patients, understood as being older than 75 years or frail. Copyright © 2017 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.
D'Amico, Elizabeth J; Tucker, Joan S; Pedersen, Eric R; Shih, Regina A
2017-01-01
There is not one answer to address whether marijuana use has increased, decreased, or stayed the same given changes in state legalization of medical and non-medical marijuana in the USA. Evidence suggests some health benefits for medical marijuana; however, initiation of marijuana use is a risk factor for developing problem cannabis use. Though use rates have remained stable over recent years, about one in three 10th graders report marijuana use, most adolescents do not view the drug as harmful, and over 650,000 youth aged 12 to 17 struggle with cannabis use disorder. Although the health benefits of medical marijuana are becoming better understood, more research is needed. Intervention and prevention programs must better address effects of marijuana, acknowledging that while there may be some benefits medically, marijuana use can affect functioning during adolescence when the brain is still developing.
Indications for IVIG in rheumatic diseases
Mulhearn, Ben
2015-01-01
The use of IVIG to treat a wide variety of immune-driven diseases has grown rapidly, although the mechanism of action is not completely understood. Increasing demand for IVIG coupled with concerns regarding potential transmissible agents has led to worldwide supply shortages. National agencies have therefore produced guidelines for its use, with the latest England and Wales guideline being published in 2011. Due to the rarity of the rheumatic diseases, the evidence for IVIG use has been shown to be lacking in some areas and promising in others. Conditions in which IVIG has been shown to have benefit include ITP, Guillain–Barré syndrome and chronic inflammatory demyelinating polyneuropathy occurring in the context of rheumatic disease, as well as in SLE, idiopathic inflammatory myopathies and ANCA-associated vasculitides. This review looks at current IVIG use and is designed to be an aid for rheumatologists when considering the use of IVIG in clinical practice. PMID:25406359
Consensus, uncertainties and challenges for perennial bioenergy crops and land use.
Whitaker, Jeanette; Field, John L; Bernacchi, Carl J; Cerri, Carlos E P; Ceulemans, Reinhart; Davies, Christian A; DeLucia, Evan H; Donnison, Iain S; McCalmont, Jon P; Paustian, Keith; Rowe, Rebecca L; Smith, Pete; Thornley, Patricia; McNamara, Niall P
2018-03-01
Perennial bioenergy crops have significant potential to reduce greenhouse gas (GHG) emissions and contribute to climate change mitigation by substituting for fossil fuels; yet delivering significant GHG savings will require substantial land-use change, globally. Over the last decade, research has delivered improved understanding of the environmental benefits and risks of this transition to perennial bioenergy crops, addressing concerns that the impacts of land conversion to perennial bioenergy crops could result in increased rather than decreased GHG emissions. For policymakers to assess the most cost-effective and sustainable options for deployment and climate change mitigation, synthesis of these studies is needed to support evidence-based decision making. In 2015, a workshop was convened with researchers, policymakers and industry/business representatives from the UK, EU and internationally. Outcomes from global research on bioenergy land-use change were compared to identify areas of consensus, key uncertainties, and research priorities. Here, we discuss the strength of evidence for and against six consensus statements summarising the effects of land-use change to perennial bioenergy crops on the cycling of carbon, nitrogen and water, in the context of the whole life-cycle of bioenergy production. Our analysis suggests that the direct impacts of dedicated perennial bioenergy crops on soil carbon and nitrous oxide are increasingly well understood and are often consistent with significant life cycle GHG mitigation from bioenergy relative to conventional energy sources. We conclude that the GHG balance of perennial bioenergy crop cultivation will often be favourable, with maximum GHG savings achieved where crops are grown on soils with low carbon stocks and conservative nutrient application, accruing additional environmental benefits such as improved water quality. The analysis reported here demonstrates there is a mature and increasingly comprehensive evidence base on the environmental benefits and risks of bioenergy cultivation which can support the development of a sustainable bioenergy industry.
Chatchaisak, Duangthip; Connor, Mark; Srikiatkhachorn, Anan; Chetsawang, Banthit
2018-05-01
Growing evidence suggests that calcitonin gene-related peptide (CGRP) participates in trigeminal nociceptive responses. However, the role of CGRP in sensitization or desensitization of nociceptive transduction remains poorly understood. In this study, we sought to further investigate the CGRP-induced up-regulation of transient receptor potential vanilloid-1 (TRPV1) and the responses of trigeminal neurons to nociceptive stimuli. Rat trigeminal ganglion (TG) organ cultures and isolated trigeminal neurons were incubated with CGRP. An increase in TRPV1 levels was observed in CGRP-incubated TG organ cultures. CGRP potentiated capsaicin-induced increase in phosphorylated CaMKII levels in the TG organ cultures. The incubation of the trigeminal neurons with CGRP significantly increased the inward currents in response to capsaicin challenge, and this effect was inhibited by co-incubation with the CGRP receptor antagonist, BIBN4068BS or the inhibitor of protein kinase A, H-89. These findings reveal that CGRP acting on trigeminal neurons may play a significant role in facilitating cellular events that contribute to the peripheral sensitization of the TG in nociceptive transmission.
Autonomic nervous system involvement in pulmonary arterial hypertension.
Vaillancourt, Mylène; Chia, Pamela; Sarji, Shervin; Nguyen, Jason; Hoftman, Nir; Ruffenach, Gregoire; Eghbali, Mansoureh; Mahajan, Aman; Umar, Soban
2017-12-04
Pulmonary arterial hypertension (PAH) is a chronic pulmonary vascular disease characterized by increased pulmonary vascular resistance (PVR) leading to right ventricular (RV) failure. Autonomic nervous system involvement in the pathogenesis of PAH has been demonstrated several years ago, however the extent of this involvement is not fully understood. PAH is associated with increased sympathetic nervous system (SNS) activation, decreased heart rate variability, and presence of cardiac arrhythmias. There is also evidence for increased renin-angiotensin-aldosterone system (RAAS) activation in PAH patients associated with clinical worsening. Reduction of neurohormonal activation could be an effective therapeutic strategy for PAH. Although therapies targeting adrenergic receptors or RAAS signaling pathways have been shown to reverse cardiac remodeling and improve outcomes in experimental pulmonary hypertension (PH)-models, the effectiveness and safety of such treatments in clinical settings have been uncertain. Recently, novel direct methods such as cervical ganglion block, pulmonary artery denervation (PADN), and renal denervation have been employed to attenuate SNS activation in PAH. In this review, we intend to summarize the multiple aspects of autonomic nervous system involvement in PAH and overview the different pharmacological and invasive strategies used to target autonomic nervous system for the treatment of PAH.
Overnutrition, mTOR signaling, and cardiovascular diseases
Jia, Guanghong; Aroor, Annayya R.; Martinez-Lemus, Luis A.
2014-01-01
The prevalence of obesity and associated medical disorders has increased dramatically in the United States and throughout much of the world in the past decade. Obesity, induced by excess intake of carbohydrates and fats, is a major cause of Type 2 diabetes, hypertension, and the cardiorenal metabolic syndrome. There is emerging evidence that excessive nutrient intake promotes signaling through the mammalian target of rapamycin (mTOR), which, in turn, may lead to alterations of cellular metabolic signaling leading to insulin resistance and obesity-related diseases, such as diabetes, cardiovascular and kidney disease, as well as cancer. While the pivotal role of mTOR signaling in regulating metabolic stress, autophagy, and adaptive immune responses has received increasing attention, there remain many gaps in our knowledge regarding this important nutrient sensor. For example, the precise cellular signaling mechanisms linking excessive nutrient intake and enhanced mTOR signaling with increased cardiovascular and kidney disease, as well as cancer, are not well understood. In this review, we focus on the effects that the interaction between excess intake of nutrients and enhanced mTOR signaling have on the promotion of obesity-associated diseases and potential therapeutic strategies involving targeting mTOR signaling. PMID:25253086
Health Implications of High-Fructose Intake and Current Research12
Dornas, Waleska C; de Lima, Wanderson G; Pedrosa, Maria L; Silva, Marcelo E
2015-01-01
Although fructose consumption has dramatically increased and is suspected to be causally linked to metabolic abnormalities, the mechanisms involved are still only partially understood. We discuss the available data and investigate the effects of dietary fructose on risk factors associated with metabolic disorders. The evidence suggests that fructose may be a predisposing cause in the development of insulin resistance in association with the induction of hypertriglyceridemia. Experiments in animals have shown this relation when they are fed diets very high in fructose or sucrose, and human studies also show this relation, although with conflicting results due to the heterogeneity of the studies. The link between increased fructose consumption and increases in uric acid also has been confirmed as a potential risk factor for metabolic syndrome, and insulin resistance/hyperinsulinemia may be causally related to the development of hypertension. Collectively, these results suggest a link between high fructose intake and insulin resistance, although future studies must be of reasonable duration, use defined populations, and improve comparisons regarding the effects of relevant doses of nutrients on specific endpoints to fully understand the effect of fructose intake in the absence of potential confounding factors. PMID:26567197
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, S. D.; Eggers, T.; Thiabgoh, O.
Understanding the relationship between the surface conditions and giant magneto-impedance (GMI) in Co-rich melt-extracted microwires is key to optimizing their magnetic responses for magnetic sensor applications. The surface magnetic domain structure (SMDS) parameters of ~45 μm diameter Co 69.25Fe 4.25Si 13B 13.5-xZr x (x = 0, 1, 2, 3) microwires, including the magnetic domain period (d) and surface roughness (Rq) as extracted from the magnetic force microscopy (MFM) images, have been correlated with GMI in the range 1–1000 MHz. It was found that substitution of B with 1 at. % Zr increased d of the base alloy from 729 tomore » 740 nm while retaining Rq from ~1 nm to ~3 nm. A tremendous impact on the GMI ratio was found, increasing the ratio from ~360% to ~490% at an operating frequency of 40 MHz. Further substitution with Zr decreased the high frequency GMI ratio, which can be understood by the significant increase in surface roughness evident by force microscopy. Lastly, this study demonstrates the application of the domain period and surface roughness found by force microscopy to the interpretation of the GMI in Co-rich microwires.« less
Effects of house prices on health: New evidence from Australia.
Atalay, Kadir; Edwards, Rebecca; Liu, Betty Y J
2017-11-01
Recent house price variation has strongly affected households' housing wealth and debt, yet the non-economic consequences of these changes in housing wealth are still poorly understood. Using a sample of 19,000 individuals from the Household, Income and Labour Dynamics in Australia Survey (HILDA) for 2001-2015, we examine the relationship between house price fluctuations and individual health by exploiting large exogenous changes in house prices in Australia. We find that an increase in local house prices is associated with a positive effect on the physical health of outright owners and a negative effect on the physical and mental health of renters. Improvements in physical health for outright owners can be partially attributed to health-related investments and behaviours such as a reduction in weight, an increase in physical exercise and an increase in time allocated to home production. These findings support the presence of a health-wealth gradient through the wealth mechanism distinct from the effects of local area amenities and macroeconomic conditions. Our findings highlight some of the often-overlooked social impacts - both positive and negative - of fluctuations in the housing market. Copyright © 2017 Elsevier Ltd. All rights reserved.
Zhang, Jian; Huang, Shongming; He, Fangliang
2015-01-01
Tree mortality, growth, and recruitment are essential components of forest dynamics and resiliency, for which there is great concern as climate change progresses at high latitudes. Tree mortality has been observed to increase over the past decades in many regions, but the causes of this increase are not well understood, and we know even less about long-term changes in growth and recruitment rates. Using a dataset of long-term (1958–2009) observations on 1,680 permanent sample plots from undisturbed natural forests in western Canada, we found that tree demographic rates have changed markedly over the last five decades. We observed a widespread, significant increase in tree mortality, a significant decrease in tree growth, and a similar but weaker trend of decreasing recruitment. However, these changes varied widely across tree size, forest age, ecozones, and species. We found that competition was the primary factor causing the long-term changes in tree mortality, growth, and recruitment. Regional climate had a weaker yet still significant effect on tree mortality, but little effect on tree growth and recruitment. This finding suggests that internal community-level processes—more so than external climatic factors—are driving forest dynamics. PMID:25775576
Zhang, Jian; Huang, Shongming; He, Fangliang
2015-03-31
Tree mortality, growth, and recruitment are essential components of forest dynamics and resiliency, for which there is great concern as climate change progresses at high latitudes. Tree mortality has been observed to increase over the past decades in many regions, but the causes of this increase are not well understood, and we know even less about long-term changes in growth and recruitment rates. Using a dataset of long-term (1958-2009) observations on 1,680 permanent sample plots from undisturbed natural forests in western Canada, we found that tree demographic rates have changed markedly over the last five decades. We observed a widespread, significant increase in tree mortality, a significant decrease in tree growth, and a similar but weaker trend of decreasing recruitment. However, these changes varied widely across tree size, forest age, ecozones, and species. We found that competition was the primary factor causing the long-term changes in tree mortality, growth, and recruitment. Regional climate had a weaker yet still significant effect on tree mortality, but little effect on tree growth and recruitment. This finding suggests that internal community-level processes-more so than external climatic factors-are driving forest dynamics.
Fahimi, Atoossa; Baktir, Mehmet Akif; Moghadam, Sarah; Mojabi, Fatemeh S; Sumanth, Krithika; McNerney, M Windy; Ponnusamy, Ravikumar; Salehi, Ahmad
2017-05-01
While it has been known that physical activity can improve cognitive function and protect against neurodegeneration, the underlying mechanisms for these protective effects are yet to be fully elucidated. There is a large body of evidence indicating that physical exercise improves neurogenesis and maintenance of neurons. Yet, its possible effects on glial cells remain poorly understood. Here, we tested whether physical exercise in mice alters the expression of trophic factor-related genes and the status of astrocytes in the dentate gyrus of the hippocampus. In addition to a significant increase in Bdnf mRNA and protein levels, we found that 4 weeks of treadmill and running wheel exercise in mice, led to (1) a significant increase in synaptic load in the dentate gyrus, (2) alterations in astrocytic morphology, and (3) orientation of astrocytic projections towards dentate granule cells. Importantly, these changes were possibly linked to increased TrkB receptor levels in astrocytes. Our study suggests that astrocytes actively respond and could indeed mediate the positive effects of physical exercise on the central nervous system and potentially counter degenerative processes during aging and neurodegenerative disorders.
Word Processing in Children With Autism Spectrum Disorders: Evidence From Event-Related Potentials.
Sandbank, Micheal; Yoder, Paul; Key, Alexandra P
2017-12-20
This investigation was conducted to determine whether young children with autism spectrum disorders exhibited a canonical neural response to word stimuli and whether putative event-related potential (ERP) measures of word processing were correlated with a concurrent measure of receptive language. Additional exploratory analyses were used to examine whether the magnitude of the association between ERP measures of word processing and receptive language varied as a function of the number of word stimuli the participants reportedly understood. Auditory ERPs were recorded in response to spoken words and nonwords presented with equal probability in 34 children aged 2-5 years with a diagnosis of autism spectrum disorder who were in the early stages of language acquisition. Average amplitudes and amplitude differences between word and nonword stimuli within 200-500 ms were examined at left temporal (T3) and parietal (P3) electrode clusters. Receptive vocabulary size and the number of experimental stimuli understood were concurrently measured using the MacArthur-Bates Communicative Development Inventories. Across the entire participant group, word-nonword amplitude differences were diminished. The average word-nonword amplitude difference at T3 was related to receptive vocabulary only if 5 or more word stimuli were understood. If ERPs are to ever have clinical utility, their construct validity must be established by investigations that confirm their associations with predictably related constructs. These results contribute to accruing evidence, suggesting that a valid measure of auditory word processing can be derived from the left temporal response to words and nonwords. In addition, this measure can be useful even for participants who do not reportedly understand all of the words presented as experimental stimuli, though it will be important for researchers to track familiarity with word stimuli in future investigations. https://doi.org/10.23641/asha.5614840.
Food Chain Mycotoxin Exposure, Gut Health, and Impaired Growth: A Conceptual Framework1
Smith, Laura E.; Stoltzfus, Rebecca J.; Prendergast, Andrew
2012-01-01
Childhood stunting is an important and intractable public health problem that underlies ∼20% of deaths among children aged <5 y in developing countries. Environmental enteropathy (EE), a subclinical condition of the small intestine characterized by reduced absorptive capacity and increased intestinal permeability, is almost universal among children in developing countries and may mediate stunting. However, the etiology of EE is poorly understood. Mycotoxins are metabolites of fungi that frequently contaminate the staple foods of children living in developing countries. We review evidence from human and animal studies that exposure to mycotoxins, particularly aflatoxin (AF), fumonisin (FUM), and deoxynivaenol (DON), may impair child growth. Although these toxins have distinct actions, they all mediate intestinal damage through: 1) inhibition of protein synthesis (AF, DON); 2) an increase in systemic proinflammatory cytokines (DON); and 3) inhibition of ceramide synthase (FUM). The intestinal pathology that arises from mycotoxin exposure is very similar to that of EE. We propose that future studies should address the role of mycotoxins in the pathogenesis of EE and evaluate interventions to limit mycotoxin exposure and reduce childhood stunting. PMID:22797988
Artificial selection reveals the energetic expense of producing larger eggs.
Pick, Joel L; Hutter, Pascale; Ebneter, Christina; Ziegler, Ann-Kathrin; Giordano, Marta; Tschirren, Barbara
2016-01-01
The amount of resources provided by the mother before birth has important and long-lasting effects on offspring fitness. Despite this, there is a large amount of variation in maternal investment seen in natural populations. Life-history theory predicts that this variation is maintained through a trade-off between the benefits of high maternal investment for the offspring and the costs of high investment for the mother. However, the proximate mechanisms underlying these costs of reproduction are not well understood. Here we used artificial selection for high and low maternal egg investment in a precocial bird, the Japanese quail (Coturnix japonica) to quantify costs of maternal reproductive investment. We show that females from the high maternal investment lines had significantly larger reproductive organs, which explained their overall larger body mass, and resulted in a higher resting metabolic rate (RMR). Contrary to our expectations, this increase in metabolic activity did not lead to a higher level of oxidative damage. This study is the first to provide experimental evidence for metabolic costs of increased per offspring investment.
Cytokines and cytokine networks target neurons to modulate long-term potentiation.
Prieto, G Aleph; Cotman, Carl W
2017-04-01
Cytokines play crucial roles in the communication between brain cells including neurons and glia, as well as in the brain-periphery interactions. In the brain, cytokines modulate long-term potentiation (LTP), a cellular correlate of memory. Whether cytokines regulate LTP by direct effects on neurons or by indirect mechanisms mediated by non-neuronal cells is poorly understood. Elucidating neuron-specific effects of cytokines has been challenging because most brain cells express cytokine receptors. Moreover, cytokines commonly increase the expression of multiple cytokines in their target cells, thus increasing the complexity of brain cytokine networks even after single-cytokine challenges. Here, we review evidence on both direct and indirect-mediated modulation of LTP by cytokines. We also describe novel approaches based on neuron- and synaptosome-enriched systems to identify cytokines able to directly modulate LTP, by targeting neurons and synapses. These approaches can test multiple samples in parallel, thus allowing the study of multiple cytokines simultaneously. Hence, a cytokine networks perspective coupled with neuron-specific analysis may contribute to delineation of maps of the modulation of LTP by cytokines. Copyright © 2017 Elsevier Ltd. All rights reserved.
Cytokines and cytokine networks target neurons to modulate long-term potentiation
Prieto, G. Aleph; Cotman, Carl W.
2017-01-01
Cytokines play crucial roles in the communication between brain cells including neurons and glia, as well as in the brain-periphery interactions. In the brain, cytokines modulate long-term potentiation (LTP), a cellular correlate of memory. Whether cytokines regulate LTP by direct effects on neurons or by indirect mechanisms mediated by non-neuronal cells is poorly understood. Elucidating neuron-specific effects of cytokines has been challenging because most brain cells express cytokine receptors. Moreover, cytokines commonly increase the expression of multiple cytokines in their target cells, thus increasing the complexity of brain cytokine networks even after single-cytokine challenges. Here, we review evidence on both direct and indirect-mediated modulation of LTP by cytokines. We also describe novel approaches based on neuron- and synaptosome-enriched systems to identify cytokines able to directly modulate LTP, by targeting neurons and synapses. These approaches can test multiple samples in parallel, thus allowing the study of multiple cytokines simultaneously. Hence, a cytokine networks perspective coupled with neuron-specific analysis may contribute to delineation of maps of the modulation of LTP by cytokines. PMID:28377062
The ortholog of the human proto-oncogene ROS1 is required for epithelial development in C. elegans
Jones, Martin R; Rose, Ann M; Baillie, David L
2013-01-01
The orphan receptor ROS1 is a human proto-oncogene, mutations of which are found in an increasing number of cancers. Little is known about the role of ROS1, however in vertebrates it has been implicated in promoting differentiation programs in specialized epithelial tissues. In this study we show that the C. elegans ortholog of ROS1, the receptor tyrosine kinase ROL-3, has an essential role in orchestrating the morphogenesis and development of specialized epidermal tissues, highlighting a potentially conserved function in coordinating crosstalk between developing epithelial cells. We also provide evidence of a direct relationship between ROL-3, the mucin SRAP-1, and BCC-1, the homolog of mRNA regulating protein Bicaudal-C. This study answers a longstanding question as to the developmental function of ROL-3, identifies three new genes that are expressed and function in the developing epithelium of C. elegans, and introduces the nematode as a potentially powerful model system for investigating the increasingly important, yet poorly understood, human oncogene ROS1. genesis 51:545–561. PMID:23733356
Early maize agriculture and interzonal interaction in southern Peru.
Perry, Linda; Sandweiss, Daniel H; Piperno, Dolores R; Rademaker, Kurt; Malpass, Michael A; Umire, Adán; de la Vera, Pablo
2006-03-02
Over the past decade, increasing attention to the recovery and identification of plant microfossil remains from archaeological sites located in lowland South America has significantly increased knowledge of pre-Columbian plant domestication and crop plant dispersals in tropical forests and other regions. Along the Andean mountain chain, however, the chronology and trajectory of plant domestication are still poorly understood for both important indigenous staple crops such as the potato (Solanum sp.) and others exogenous to the region, for example, maize (Zea mays). Here we report the analyses of plant microremains from a late preceramic house (3,431 +/- 45 to 3,745 +/- 65 14C bp or approximately 3,600 to 4,000 calibrated years bp) in the highland southern Peruvian site of Waynuna. Our results extend the record of maize by at least a millennium in the southern Andes, show on-site processing of maize into flour, provide direct evidence for the deliberate movement of plant foods by humans from the tropical forest to the highlands, and confirm the potential of plant microfossil analysis in understanding ancient plant use and migration in this region.
Kraakman, Michael J; Dragoljevic, Dragana; Kammoun, Helene L; Murphy, Andrew J
2016-01-01
Cardiovascular disease (CVD) remains the leading cause of mortality worldwide. Atherosclerosis is the most common form of CVD, which is complex and multifactorial with an elevated risk observed in people with either metabolic or inflammatory diseases. Accumulating evidence now links obesity with a state of chronic low-grade inflammation and has renewed our understanding of this condition and its associated comorbidities. An emerging theme linking disease states with atherosclerosis is the increased production of myeloid cells, which can initiate and exacerbate atherogenesis. Although anti-inflammatory drug treatments exist and have been successfully used to treat inflammatory conditions such as rheumatoid arthritis (RA), a commonly observed side effect is dyslipidemia, inadvertently, a major risk factor for the development of atherosclerosis. The mechanisms leading to dyslipidemia associated with anti-inflammatory drug use and whether CVD risk is actually increased by this dyslipidemia are of great therapeutic importance and currently remain poorly understood. Here we review recent data providing links between inflammation, hematopoiesis, dyslipidemia and CVD risk in the context of anti-inflammatory drug use. PMID:27350883
Déjà Vu: An Illusion of Prediction.
Cleary, Anne M; Claxton, Alexander B
2018-04-01
Déjà vu is beginning to be scientifically understood as a memory phenomenon. Despite recent scientific advances, a remaining puzzle is the purported association between déjà vu and feelings of premonition. Building on research showing that déjà vu can be driven by an unrecalled memory of a past experience that relates to the current situation, we sought evidence of memory-based predictive ability during déjà vu states. Déjà vu did not lead to above-chance ability to predict the next turn in a navigational path resembling a previously experienced but unrecalled path (although such resemblance increased reports of déjà vu). However, déjà vu states were accompanied by increased feelings of knowing the direction of the next turn. The results suggest that feelings of premonition during déjà vu occur and can be illusory. Metacognitive bias brought on by the state itself may explain the peculiar association between déjà vu and the feeling of premonition.
Matsuo, Hidemasa; Itoh, Hiroshi; Kitamura, Naoko; Kamikubo, Yasuhiko; Higuchi, Takeshi; Shiga, Shuichi; Ichiyama, Satoshi; Kondo, Tadakazu; Takaori-Kondo, Akifumi; Adachi, Souichi
2015-08-14
Intravenous immunoglobulin (IVIG) is periodically administered to immunocompromised patients together with antimicrobial agents. The evidence that supports the effectiveness of IVIG is mostly based on data from randomized clinical trials; the underlying mechanisms are poorly understood. A recent study revealed that killing of multidrug-resistant bacteria and drug-sensitive strains by neutrophils isolated from healthy donors is enhanced by an IVIG preparation. However, the effectiveness of IVIG in immunocompromised patients remains unclear. The present study found that IVIG increased both killing activity and O2(-) release by neutrophils isolated from six patients receiving immune-suppressive drugs after hematopoietic stem cell transplantation (HSCT); these neutrophils killed both multidrug-resistant extended-spectrum β-lactamase-producing Escherichia coli (E. coli) and multidrug-resistant Pseudomonas aeruginosa (P. aeruginosa). Moreover, IVIG increased the autophagy of the neutrophils, which is known to play an important role in innate immunity. These results suggest that IVIG promotes both the killing activity and autophagy of neutrophils isolated from immunocompromised patients against multidrug-resistant bacteria. Copyright © 2015 Elsevier Inc. All rights reserved.
Dazzle camouflage, target tracking, and the confusion effect.
Hogan, Benedict G; Cuthill, Innes C; Scott-Samuel, Nicholas E
2016-01-01
The influence of coloration on the ecology and evolution of moving animals in groups is poorly understood. Animals in groups benefit from the "confusion effect," where predator attack success is reduced with increasing group size or density. This is thought to be due to a sensory bottleneck: an increase in the difficulty of tracking one object among many. Motion dazzle camouflage has been hypothesized to disrupt accurate perception of the trajectory or speed of an object or animal. The current study investigates the suggestion that dazzle camouflage may enhance the confusion effect. Utilizing a computer game style experiment with human predators, we found that when moving in groups, targets with stripes parallel to the targets' direction of motion interact with the confusion effect to a greater degree, and are harder to track, than those with more conventional background matching patterns. The findings represent empirical evidence that some high-contrast patterns may benefit animals in groups. The results also highlight the possibility that orientation and turning may be more relevant in the mechanisms of dazzle camouflage than previously recognized.
Lou, Xuelin
2018-01-01
The intact synaptic structure is critical for information processing in neural circuits. During synaptic transmission, rapid vesicle exocytosis increases the size of never terminals and endocytosis counteracts the increase. Accumulating evidence suggests that SV exocytosis and endocytosis are tightly connected in time and space during SV recycling, and this process is essential for synaptic function and structural stability. Research in the past has illustrated the molecular details of synaptic vesicle (SV) exocytosis and endocytosis; however, the mechanisms that timely connect these two fundamental events are poorly understood at central synapses. Here we discuss recent progress in SV recycling and summarize several emerging mechanisms by which synapses can “sense” the occurrence of exocytosis and timely initiate compensatory endocytosis. They include Ca2+ sensing, SV proteins sensing, and local membrane stress sensing. In addition, the spatial organization of endocytic zones adjacent to active zones provides a structural basis for efficient coupling between SV exocytosis and endocytosis. Through linking different endocytosis pathways with SV fusion, these mechanisms ensure necessary plasticity and robustness of nerve terminals to meet diverse physiological needs. PMID:29593500
Zavala, Baltazar; Damera, Srikanth; Dong, Jian Wilson; Lungu, Codrin; Brown, Peter; Zaghloul, Kareem A.
2017-01-01
Recent evidence has suggested that prefrontal cortical structures may inhibit impulsive actions during conflict through activation of the subthalamic nucleus (STN). Consistent with this hypothesis, deep brain stimulation to the STN has been associated with altered prefrontal cortical activity and impaired response inhibition. The interactions between oscillatory activity in the STN and its presumably antikinetic neuronal spiking, however, remain poorly understood. Here, we simultaneously recorded intraoperative local field potential and spiking activity from the human STN as participants performed a sensorimotor action selection task involving conflict. We identified several STN neuronal response types that exhibited different temporal dynamics during the task. Some neurons showed early, cue-related firing rate increases that remained elevated longer during high conflict trials, whereas other neurons showed late, movement-related firing rate increases. Notably, the high conflict trials were associated with an entrainment of individual neurons by theta- and beta-band oscillations, both of which have been observed in cortical structures involved in response inhibition. Our data suggest that frequency-specific activity in the beta and theta bands influence STN firing to inhibit impulsivity during conflict. PMID:26494798
Divided attention disrupts perceptual encoding during speech recognition.
Mattys, Sven L; Palmer, Shekeila D
2015-03-01
Performing a secondary task while listening to speech has a detrimental effect on speech processing, but the locus of the disruption within the speech system is poorly understood. Recent research has shown that cognitive load imposed by a concurrent visual task increases dependency on lexical knowledge during speech processing, but it does not affect lexical activation per se. This suggests that "lexical drift" under cognitive load occurs either as a post-lexical bias at the decisional level or as a secondary consequence of reduced perceptual sensitivity. This study aimed to adjudicate between these alternatives using a forced-choice task that required listeners to identify noise-degraded spoken words with or without the addition of a concurrent visual task. Adding cognitive load increased the likelihood that listeners would select a word acoustically similar to the target even though its frequency was lower than that of the target. Thus, there was no evidence that cognitive load led to a high-frequency response bias. Rather, cognitive load seems to disrupt sublexical encoding, possibly by impairing perceptual acuity at the auditory periphery.
Dim Light at Night Disrupts Molecular Circadian Rhythms and Affects Metabolism
Fonken, Laura K.; Aubrecht, Taryn G.; Meléndez-Fernández, O. Hecmarie; Weil, Zachary M.; Nelson, Randy J.
2014-01-01
With the exception of high latitudes, life has evolved under bright days and dark nights. Most organisms have developed endogenously driven circadian rhythms which are synchronized to this daily light/dark cycle. In recent years, humans have shifted away from the naturally occurring solar light cycle in favor of artificial and sometimes irregular light schedules produced by electrical lighting. Exposure to unnatural light cycles is increasingly associated with obesity and metabolic syndrome; however the means by which environmental lighting alters metabolism are poorly understood. Thus, we exposed mice to nighttime light and investigated changes in the circadian system and body weight. Here we report that exposure to ecologically relevant levels of dim (5 lux) light at night attenuate core circadian clock rhythms in the SCN at both the gene and protein level. Moreover, circadian clock rhythms were perturbed in the liver by nighttime light exposure. Changes in the circadian clock were associated with temporal alterations in feeding behavior and increased weight gain. These results are significant because they provide mechanistic evidence for how mild changes in environmental lighting can alter circadian and metabolic function. PMID:23929553
Prevention of SHIV transmission by topical IFN-β treatment.
Veazey, R S; Pilch-Cooper, H A; Hope, T J; Alter, G; Carias, A M; Sips, M; Wang, X; Rodriguez, B; Sieg, S F; Reich, A; Wilkinson, P; Cameron, M J; Lederman, M M
2016-11-01
Understanding vaginal and rectal HIV transmission and protective cellular and molecular mechanisms is critical for designing new prevention strategies, including those required for an effective vaccine. The determinants of protection against HIV infection are, however, poorly understood. Increasing evidence suggest that innate immune defenses may help protect mucosal surfaces from HIV transmission in highly exposed, uninfected subjects. More recent studies suggest that systemically administered type 1 interferon protects against simian immunodeficiency virus infection of macaques. Here we hypothesized that topically applied type 1 interferons might stimulate vaginal innate responses that could protect against HIV transmission. We therefore applied a recombinant human type 1 interferon (IFN-β) to the vagina of rhesus macaques and vaginally challenged them with pathogenic simian/human immunodeficiency virus (SHIV). Vaginal administration of IFN-β resulted in marked local changes in immune cell phenotype, increasing immune activation and HIV co-receptor expression, yet provided significant protection from SHIV acquisition as interferon response genes were also upregulated. These data suggest that protection from vaginal HIV acquisition may be achieved by activating innate mucosal defenses.
Stressful Life Events, Anxiety Sensitivity, and Internalizing Symptoms in Adolescents
McLaughlin, Katie A.; Hatzenbuehler, Mark L.
2010-01-01
Anxiety sensitivity represents a robust risk factor for the development of anxiety symptoms among both adolescents and adults. However, the development of anxiety sensitivity among adolescents remains inadequately understood. In this study, the authors examined the role of stressful life events as a risk factor for the development of elevated anxiety sensitivity. Anxiety sensitivity was then examined in a longitudinal design as a mechanism linking stressful life events to changes in anxiety symptoms. Stressful life events, anxiety sensitivity, and internalizing symptoms were assessed in a diverse community sample of adolescents (N = 1,065) at 3 time points spanning 7 months. The results indicated that stressful life events were longitudinally associated with increases in anxiety sensitivity and that certain types of stressful life events, specifically events related to health and events related to family discord, were differentially predictive of increases in anxiety sensitivity. Moreover, anxiety sensitivity mediated the longitudinal relation between stressful life events and anxiety symptoms. Evidence was also found for the predictive specificity of anxiety sensitivity to symptoms of anxiety but not depression. PMID:19685962
Stressful life events, anxiety sensitivity, and internalizing symptoms in adolescents.
McLaughlin, Katie A; Hatzenbuehler, Mark L
2009-08-01
Anxiety sensitivity represents a robust risk factor for the development of anxiety symptoms among both adolescents and adults. However, the development of anxiety sensitivity among adolescents remains inadequately understood. In this study, the authors examined the role of stressful life events as a risk factor for the development of elevated anxiety sensitivity. Anxiety sensitivity was then examined in a longitudinal design as a mechanism linking stressful life events to changes in anxiety symptoms. Stressful life events, anxiety sensitivity, and internalizing symptoms were assessed in a diverse community sample of adolescents (N = 1,065) at 3 time points spanning 7 months. The results indicated that stressful life events were longitudinally associated with increases in anxiety sensitivity and that certain types of stressful life events, specifically events related to health and events related to family discord, were differentially predictive of increases in anxiety sensitivity. Moreover, anxiety sensitivity mediated the longitudinal relation between stressful life events and anxiety symptoms. Evidence was also found for the predictive specificity of anxiety sensitivity to symptoms of anxiety but not depression.
Seasonally asymmetric enhancement of northern vegetation productivity
NASA Astrophysics Data System (ADS)
Park, T.; Myneni, R.
2017-12-01
Multiple evidences of widespread greening and increasing terrestrial carbon uptake have been documented. In particular, enhanced gross productivity of northern vegetation has been a critical role leading to observed carbon uptake trend. However, seasonal photosynthetic activity and its contribution to observed annual carbon uptake trend and interannual variability are not well understood. Here, we introduce a multiple-source of datasets including ground, atmospheric and satellite observations, and multiple process-based global vegetation models to understand how seasonal variation of land surface vegetation controls a large-scale carbon exchange. Our analysis clearly shows a seasonally asymmetric enhancement of northern vegetation productivity in growing season during last decades. Particularly, increasing gross productivity in late spring and early summer is obvious and dominant driver explaining observed trend and variability. We observe more asymmetric productivity enhancement in warmer region and this spatially varying asymmetricity in northern vegetation are likely explained by canopy development rate, thermal and light availability. These results imply that continued warming may facilitate amplifying asymmetric vegetation activity and cause these trends to become more pervasive, in turn warming induced regime shift in northern land.
Physical activity in obesity and metabolic syndrome
Strasser, Barbara
2013-01-01
Biological aging is typically associated with a progressive increase in body fat mass and a loss of lean body mass. Owing to the metabolic consequences of reduced muscle mass, it is understood that normal aging and/or decreased physical activity may lead to a higher prevalence of metabolic disorders. Lifestyle modification, specifically changes in diet, physical activity, and exercise, is considered the cornerstone of obesity management. However, for most overweight people it is difficult to lose weight permanently through diet or exercise. Thus, prevention of weight gain is thought to be more effective than weight loss in reducing obesity rates. A key question is whether physical activity can extenuate age-related weight gain and promote metabolic health in adults. Current guidelines suggest that adults should accumulate about 60 minutes of moderate-intensity physical activity daily to prevent unhealthy weight gain. Because evidence suggests that resistance training may promote a negative energy balance and may change body fat distribution, it is possible that an increase in muscle mass after resistance training may be a key mediator leading to better metabolic control. PMID:23167451
The maternal womb: a novel target for cancer prevention in the era of the obesity pandemic?
Simmen, Frank A.; Simmen, Rosalia C.M.
2011-01-01
The dramatic rise in worldwide prevalence of obesity has necessitated the search for more efficacious anti-obesity strategies to counter the increased cancer risks in overweight and obese individuals. The mechanistic pathways linking obesity status with adult chronic diseases such as cancer remain incompletely understood. A growing body of evidence suggests that novel approaches and interventional agents to disrupt the feed-forward cycle of maternal to offspring obesity transfer that is initiated in utero, will be important for stemming both the obesity pandemic and the associated increase in cancer incidence. The convergence of multiple research areas including those encompassing the insulin and insulin-like growth factor (IGF) systems, epigenetics, and stem cell biology is providing insights into the potential for cancer prevention in adult offspring previously exposed to the intrauterine environment of overweight/obese mothers. Here, we review the current state of this nascent research field, with a focus on three major cancers namely breast, colorectal and liver, and suggest some possible future directions to optimize its impact for the health of future generations. PMID:21701386
Metacognition and evidence analysis instruction: an educational framework and practical experience.
Parrott, J Scott; Rubinstein, Matthew L
2015-08-21
The role of metacognitive skills in the evidence analysis process has received little attention in the research literature. While the steps of the evidence analysis process are well defined, the role of higher-level cognitive operations (metacognitive strategies) in integrating the steps of the process is not well understood. In part, this is because it is not clear where and how metacognition is implicated in the evidence analysis process nor how these skills might be taught. The purposes of this paper are to (a) suggest a model for identifying critical thinking and metacognitive skills in evidence analysis instruction grounded in current educational theory and research and (b) demonstrate how freely available systematic review/meta-analysis tools can be used to focus on higher-order metacognitive skills, while providing a framework for addressing common student weaknesses. The final goal of this paper is to provide an instructional framework that can generate critique and elaboration while providing the conceptual basis and rationale for future research agendas on this topic.
Adding the Fourth "R": A Systems Approach to Solving the Hacker's Arms Race
DOE Office of Scientific and Technical Information (OSTI.GOV)
Endicott-Popovsky, Barbara E.; Frincke, Deborah A.
2006-01-01
In this paper, the authors propose a modification of CERT's 3 R model to include a 4 th R, the discipline of Redress, identified as a necessary step to end the hacker arms race. Redress will require implementation of computer forensic investigation methods, tools and techniques that will permit evidence gathered to be admissible in a court of law, a standard not often understood or followed by many who are responsible for securing networks today. This leads the authors to conclude that there is a need for future work that will involve re-examination of the mechanisms and procedures used tomore » collect evidence of network intrusions in order to ensure that the Rules of Evidence requirements are considered.« less
Learning words and learning sounds: Advances in language development.
Vihman, Marilyn M
2017-02-01
Phonological development is sometimes seen as a process of learning sounds, or forming phonological categories, and then combining sounds to build words, with the evidence taken largely from studies demonstrating 'perceptual narrowing' in infant speech perception over the first year of life. In contrast, studies of early word production have long provided evidence that holistic word learning may precede the formation of phonological categories. In that account, children begin by matching their existing vocal patterns to adult words, with knowledge of the phonological system emerging from the network of related word forms. Here I review evidence from production and then consider how the implicit and explicit learning mechanisms assumed by the complementary memory systems model might be understood as reconciling the two approaches. © 2016 The British Psychological Society.
Thomas E. Ingersoll; Brent J. Sewall; Sybill K. Amelon
2013-01-01
Bats are diverse and ecologically important, but are also subject to a suite of severe threats. Evidence for localized bat mortality from these threats is well-documented in some cases, but long-term changes in regional populations of bats remain poorly understood. Bat hibernation surveys provide an opportunity to improve understanding, but analysis is complicated by...
ERIC Educational Resources Information Center
Jara-Ettinger, Julian; Piantadosi, Steve; Spelke, Elizabeth S.; Levy, Roger; Gibson, Edward
2017-01-01
To master the natural number system, children must understand both the concepts that number words capture and the counting procedure by which they are applied. These two types of knowledge develop in childhood, but their connection is poorly understood. Here we explore the relationship between the mastery of counting and the mastery of exact…
ERIC Educational Resources Information Center
Dilnot, Catherine
2016-01-01
The reasons why students from lower socio-economic groups are under-represented at high status universities are not yet entirely understood, but evidence suggests that part of the gap may be a consequence of differential choice of A-levels by social background. The Russell Group of universities has since 2011 published guidance on A-level subject…
ERIC Educational Resources Information Center
Allan, Nicholas P.; Hume, Laura E.; Allan, Darcey M.; Farrington, Amber L.; Lonigan, Christopher J.
2014-01-01
Although there is evidence that young children's inhibitory control (IC) is related to their academic skills, the nature of this relation and the role of potential moderators of it are not well understood. In this meta-analytic study, we summarized results from 75 peer-reviewed studies of preschool and kindergarten children (14,424 children; 32-80…
Human Papilloma Viral DNA Replicates as a Stable Episome in Cultured Epidermal Keratinocytes
NASA Astrophysics Data System (ADS)
Laporta, Robert F.; Taichman, Lorne B.
1982-06-01
Human papilloma virus (HPV) is poorly understood because systems for its growth in tissue culture have not been developed. We report here that cultured human epidermal keratinocytes could be infected with HPV from plantar warts and that the viral DNA persisted and replicated as a stable episome. There were 50-200 copies of viral DNA per cell and there was no evidence to indicate integration of viral DNA into the cellular genome. There was also no evidence to suggest that viral DNA underwent productive replication. We conclude that cultured human epidermal keratinocytes may be a model for the study of certain aspects of HPV biology.
Shaffer, Susan T; Zarnowsky, Colleen D; Green, Renee C; Lim, Mei-Lin Chen; Holtzer, Brenda M; Ely, Elizabeth A
2013-06-01
This article presents the bedside nurses' perspectives on their experience with conducting an evidence based practice project. This is especially important in the climate of hospitals working to achieve Magnet Recognition. The facilitators and barriers to project design and completion are discussed in detail. Strategies to overcome barriers are presented. Facilitators for bedside nurses include motivation and professional development. Most common barriers were lack of time and limited knowledge about the process. Interventions aimed at research utilization can be successful when mindful of commonly understood barriers to project completion with steps taken to resolve those barriers. Copyright © 2013 Elsevier Inc. All rights reserved.
Beyond Denomination: The Relationship between Religion and Family Planning in Rural Malawi
Yeatman, Sara E.; Trinitapoli, Jenny
2010-01-01
Despite the centrality of religion and fertility to life in rural Africa, the relationship between the two remains poorly understood. The study presented here uses unique integrated individual and congregational level data from rural Malawi to examine religious influences on contraceptive use. In this religiously diverse population, we find evidence that the particular characteristics of a congregation—leader’s positive attitudes toward family planning and discussion of sexual morality, which do not fall along broad denominational lines—are more relevant than denominational categories for predicting women’s contraceptive use. We further find evidence for a relationship between religious socialization and contraceptive behavior. PMID:20463916
How does the brain solve visual object recognition?
Zoccolan, Davide; Rust, Nicole C.
2012-01-01
Mounting evidence suggests that “core object recognition,” the ability to rapidly recognize objects despite substantial appearance variation, is solved in the brain via a cascade of reflexive, largely feedforward computations that culminate in a powerful neuronal representation in the inferior temporal cortex. However, the algorithm that produces this solution remains little-understood. Here we review evidence ranging from individual neurons, to neuronal populations, to behavior, to computational models. We propose that understanding this algorithm will require using neuronal and psychophysical data to sift through many computational models, each based on building blocks of small, canonical sub-networks with a common functional goal. PMID:22325196
Nitrate photolysis in salty snow
NASA Astrophysics Data System (ADS)
Donaldson, D. J.; Morenz, K.; Shi, Q.; Murphy, J. G.
2016-12-01
Nitrate photolysis from snow can have a significant impact on the oxidative capacity of the local atmosphere, but the factors affecting the release of gas phase products are not well understood. Here, we report the first systematic study of the amounts of NO, NO2, and total nitrogen oxides (NOy) emitted from illuminated snow samples as a function of both nitrate and total salt (NaCl and Instant Ocean) concentration. We show that the release of nitrogen oxides to the gas phase is directly related to the expected nitrate concentration in the brine at the surface of the snow crystals, increasing to a plateau value with increasing nitrate, and generally decreasing with increasing NaCl or Instant Ocean (I.O.). In frozen mixed nitrate (25 mM) - salt (0-500 mM) solutions, there is an increase in gas phase NO2 seen at low added salt amounts: NO2 production is enhanced by 35% at low prefreezing [NaCl] and by 70% at similar prefreezing [I.O.]. Raman microscopy of frozen nitrate-salt solutions shows evidence of stronger nitrate exclusion to the air interface in the presence of I.O. than with added NaCl. The enhancement in nitrogen oxides emission in the presence of salts may prove to be important to the atmospheric oxidative capacity in polar regions.
Self-Referential Processing, Rumination, and Cortical Midline Structures in Major Depression
Nejad, Ayna Baladi; Fossati, Philippe; Lemogne, Cédric
2013-01-01
Major depression is associated with a bias toward negative emotional processing and increased self-focus, i.e., the process by which one engages in self-referential processing. The increased self-focus in depression is suggested to be of a persistent, repetitive and self-critical nature, and is conceptualized as ruminative brooding. The role of the medial prefrontal cortex in self-referential processing has been previously emphasized in acute major depression. There is increasing evidence that self-referential processing as well as the cortical midline structures play a major role in the development, course, and treatment response of major depressive disorder. However, the links between self-referential processing, rumination, and the cortical midline structures in depression are still poorly understood. Here, we reviewed brain imaging studies in depressed patients and healthy subjects that have examined these links. Self-referential processing in major depression seems associated with abnormally increased activity of the anterior cortical midline structures. Abnormal interactions between the lateralized task-positive network, and the midline cortical structures of the default mode network, as well as the emotional response network, may underlie the pervasiveness of ruminative brooding. Furthermore, targeting this maladaptive form of rumination and its underlying neural correlates may be key for effective treatment. PMID:24124416
Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice.
Cahill, Lindsay S; Gazdzinski, Lisa M; Tsui, Albert Ky; Zhou, Yu-Qing; Portnoy, Sharon; Liu, Elaine; Mazer, C David; Hare, Gregory Mt; Kassner, Andrea; Sled, John G
2017-03-01
Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO 2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia.
Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice
Gazdzinski, Lisa M; Tsui, Albert KY; Zhou, Yu-Qing; Portnoy, Sharon; Liu, Elaine; Mazer, C David; Hare, Gregory MT; Kassner, Andrea; Sled, John G
2016-01-01
Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia. PMID:27165012
HFE interacts with the BMP type I receptor ALK3 to regulate hepcidin expression
Wu, Xing-gang; Wang, Yang; Wu, Qian; Cheng, Wai-Hang; Liu, Wenjing; Zhao, Yueshui; Mayeur, Claire; Schmidt, Paul J.; Yu, Paul B.; Wang, Fudi
2014-01-01
Mutations in HFE are the most common cause of hereditary hemochromatosis (HH). HFE mutations result in reduced expression of hepcidin, a hepatic hormone, which negatively regulates iron absorption from the duodenum and iron release from macrophages. However, the mechanism by which HFE regulates hepcidin expression in hepatocytes is not well understood. It is known that the bone morphogenetic protein (BMP) pathway plays a central role in controlling hepcidin expression in the liver. Here we show that HFE overexpression increased Smad1/5/8 phosphorylation and hepcidin expression, whereas inhibition of BMP signaling abolished HFE-induced hepcidin expression in Hep3B cells. HFE was found to associate with ALK3, inhibiting ALK3 ubiquitination and proteasomal degradation and increasing ALK3 protein expression and accumulation on the cell surface. The 2 HFE mutants associated with HH, HFE C282Y and HFE H63D, regulated ALK3 protein ubiquitination and trafficking differently, but both failed to increase ALK3 cell-surface expression. Deletion of Hfe in mice resulted in a decrease in hepatic ALK3 protein expression. Our results provide evidence that HFE induces hepcidin expression via the BMP pathway: HFE interacts with ALK3 to stabilize ALK3 protein and increase ALK3 expression at the cell surface. PMID:24904118
NASA Astrophysics Data System (ADS)
Geng, Yan; Baumann, Frank; Song, Chao; Zhang, Mi; Shi, Yue; Kühn, Peter; Scholten, Thomas; He, Jin-Sheng
2017-03-01
Changes in climatic conditions along geographical gradients greatly affect soil nutrient cycling processes. Yet how climate regimes such as changes in temperature influence soil nitrogen (N) and phosphorus (P) concentrations and their stoichiometry is not well understood. This study investigated the spatial pattern and variability of soil N and P availability as well as their coupling relationships at two soil layers (0-10 and 10-20 cm) along a 4000-km climate transect in two grassland biomes of China, the Inner Mongolian temperate grasslands and the Tibetan alpine grasslands. Our results found that in both grasslands, from cold to warm sites the amounts of soil total N, total P and available P all decreased. By contrast, the amount of available N was positively related to mean annual temperature in the Tibetan grasslands. Meanwhile, with increasing temperature ratio of available N to P significantly increased but the linear relationship between them was considerably reduced. Thus, increasing temperature may not only induce a stoichiometric shift but also loose the coupling between available N and P. This N-P decoupling under warmer conditions was more evident in the Tibetan alpine grasslands where P limitation might become more widespread relative to N as temperatures continue to rise.
NASA Astrophysics Data System (ADS)
Chen, A.; Tan, J.; Piao, S.
2014-12-01
Weather events that are located in the tails of a weather distribution are called weather extremes. Weather extremes, including severe drought, flooding, heat and cold waves, usually can cause greatest damage to human lives and properties, and have profound implication on ecosystem productivity and carbon cycles. There is mounting evidence suggests that the frequency of temperature and hydrological weather extremes have steadily increased over the last decades, largely due to the ongoing climate change. On the other hand, the distribution and trend of weather extremes can be regionally heterogeneous, which have not been well understood. Here we investigate the spatial distribution and temporal trend of weather extremes in the Northern Hemisphere (NH) over the past half century (1961-2010), with emphasis on the intercontinental comparisons. Our results suggest that warming extremes have increased significantly in East Asia and West Europe; while coldness extremes have decreased globally. Heavy precipitation extremes significantly increased in eastern Northern America, boreal Eurasia, and some parts of China; while drought events showed an increasing trend in northern China-southern Mongolia and some parts of western United States. Our results highlight the regional difference in the trend of weather extremes, which need to be incorporated in the mitigation measures.
van Dijk, René E; Eising, Corine M; Merrill, Richard M; Karadas, Filiz; Hatchwell, Ben; Spottiswoode, Claire N
2013-02-01
Maternal effects can influence offspring phenotype with short- and long-term consequences. Yet, how the social environment may influence egg composition is not well understood. Here, we investigate how laying order and social environment predict maternal effects in the sociable weaver, Philetairus socius, a species that lives in massive communal nests which may be occupied by only a few to 100+ individuals in a single nest. This range of social environments is associated with variation in a number of phenotypic and life-history traits. We investigate whether maternal effects are adjusted accordingly. We found no evidence for the prediction that females might benefit from modifying brood hierarchies through an increased deposition of androgens with laying order. Instead, females appear to exacerbate brood reduction by decreasing the costly production of yolk mass and antioxidants with laying order. Additionally, we found that this effect did not depend on colony size. Finally, in accordance with an expected increased intensity of environmental stress with increasing colony size, we found that yolk androgen concentration increased with colony size. This result suggests that females may enhance the competitive ability of offspring raised in larger colonies, possibly preparing the offspring for a competitive social environment.
Effects of host injury on susceptibility of marine reef fishes to ectoparasitic gnathiid isopods
Jenkins, William G.; Demopoulos, Amanda W.J.; Sikkel, Paul C.
2018-01-01
The importance of the role that parasites play in ecological communities is becoming increasingly apparent. However much about their impact on hosts and thus populations and communities remains poorly understood. A common observation in wild populations is high variation in levels of parasite infestation among hosts. While high variation could be due to chance encounter, there is increasing evidence to suggest that such patterns are due to a combination of environmental, host, and parasite factors. In order to examine the role of host condition on parasite infection, rates of Gnathia marleyi infestation were compared between experimentally injured and uninjured fish hosts. Experimental injuries were similar to the minor wounds commonly observed in nature. The presence of the injury significantly increased the probability of infestation by gnathiids. However, the level of infestation (i.e., total number of gnathiid parasites) for individual hosts, appeared to be unaffected by the treatment. The results from this study indicate that injuries obtained by fish in nature may carry the additional cost of increased parasite burden along with the costs typically associated with physical injury. These results suggest that host condition may be an important factor in determining the likelihood of infestation by a common coral reef fish ectoparasite, G. marleyi.
Evidence of population resistance to extreme low flows in a fluvial-dependent fish species
Katz, Rachel A.; Freeman, Mary C.
2015-01-01
Extreme low streamflows are natural disturbances to aquatic populations. Species in naturally intermittent streams display adaptations that enhance persistence during extreme events; however, the fate of populations in perennial streams during unprecedented low-flow periods is not well-understood. Biota requiring swift-flowing habitats may be especially vulnerable to flow reductions. We estimated the abundance and local survival of a native fluvial-dependent fish species (Etheostoma inscriptum) across 5 years encompassing historic low flows in a sixth-order southeastern USA perennial river. Based on capturemark-recapture data, the study shoal may have acted as a refuge during severe drought, with increased young-of-the-year (YOY) recruitment and occasionally high adult immigration. Contrary to expectations, summer and autumn survival rates (30 days) were not strongly depressed during low-flow periods, despite 25%-80% reductions in monthly discharge. Instead, YOY survival increased with lower minimum discharge and in response to small rain events that increased low-flow variability. Age-1+ fish showed the opposite pattern, with survival decreasing in response to increasing low-flow variability. Results from this population dynamics study of a small fish in a perennial river suggest that fluvial-dependent species can be resistant to extreme flow reductions through enhanced YOY recruitment and high survival
Yan, Dan; Avtanski, Dimiter; Saxena, Neeraj K.; Sharma, Dipali
2012-01-01
Perturbations in the adipocytokine profile, especially higher levels of leptin, are a major cause of breast tumor progression and metastasis; the underlying mechanisms, however, are not well understood. In particular, it remains elusive whether leptin is involved in epithelial-mesenchymal transition (EMT). Here, we provide molecular evidence that leptin induces breast cancer cells to undergo a transition from epithelial to spindle-like mesenchymal morphology. Investigating the downstream mediator(s) that may direct leptin-induced EMT, we found functional interactions between leptin, metastasis-associated protein 1 (MTA1), and Wnt1 signaling components. Leptin increases accumulation and nuclear translocation of β-catenin leading to increased promoter recruitment. Silencing of β-catenin or treatment with the small molecule inhibitor, ICG-001, inhibits leptin-induced EMT, invasion, and tumorsphere formation. Mechanistically, leptin stimulates phosphorylation of glycogen synthase kinase 3β (GSK3β) via Akt activation resulting in a substantial decrease in the formation of the GSK3β-LKB1-Axin complex that leads to increased accumulation of β-catenin. Leptin treatment also increases Wnt1 expression that contributes to GSK3β phosphorylation. Inhibition of Wnt1 abrogates leptin-stimulated GSK3β phosphorylation. We also discovered that leptin increases the expression of an important modifier of Wnt1 signaling, MTA1, which is integral to leptin-mediated regulation of the Wnt/β-catenin pathway as silencing of MTA1 inhibits leptin-induced Wnt1 expression, GSK3β phosphorylation, and β-catenin activation. Furthermore, analysis of leptin-treated breast tumors shows increased expression of Wnt1, pGSK3β, and vimentin along with higher nuclear accumulation of β-catenin and reduced E-cadherin expression providing in vivo evidence for a previously unrecognized cross-talk between leptin and MTA1/Wnt signaling in epithelial-mesenchymal transition of breast cancer cells. PMID:22270359
Social and ecological correlates of space use patterns in Bwindi mountain gorillas.
Seiler, Nicole; Boesch, Christophe; Stephens, Colleen; Ortmann, Sylvia; Mundry, Roger; Robbins, Martha M
2018-04-01
Space use patterns determine access to resources necessary for survival and reproduction. Although it is recognized that the interplay between social and ecological variables shapes spacing patterns, few studies in group-living animals have simultaneously assessed their importance in a comprehensive approach using different spatiotemporal space use measures. In territorial species, such patterns are strongly determined by between-group competition, but its impact in non-territorial species is poorly understood. To better understand the role of social and ecological variables in non-territorial mountain gorillas (Gorilla beringei beringei), we simultaneously evaluated the impact of between-group competition (local gorilla population density and frequency of intergroup encounters) and within-group competition (group size) on space use patterns in 13 gorilla groups in Bwindi Impenetrable National Park, Uganda, while also examining variation in food availability (herbaceous food availability and level of frugivory). We found evidence of between-group competition, indicated by a decline of both monthly home range size and frequency of revisits to each part of the home range as the local gorilla population density increased and by an increase in daily travel distance on days when intergroup encounters occurred. Within-group feeding competition was inferred by a decrease in the frequency of revisits as group size increased. Lastly, food availability influenced the gorillas' spacing patterns, as indicated by a decline in monthly home range size as herbaceous food availability increased and by an increase in daily travel distance as the degree of frugivory increased. In sum, our results suggest that Bwindi gorillas adapted their space use according to the constraints of intraspecific competition and the availability of food resources. We provide some of the first evidence of between-group competition influencing spacing patterns in a non-territorial species. This study suggests a gradient between territoriality and non-territoriality, along which the level of between-group competition varies. © 2018 Wiley Periodicals, Inc.
Presser - the forgotten story.
Kasinathan, John; Le, Joey; Barker, Anthony; Sharp, Gillian
2016-10-01
Regina v Presser [1958] VR 45, is the most seminal case regarding fitness to plead for accused persons in Australia and New Zealand. It is not widely understood that Presser was a 14-year-old boy with intellectual disability. We aim to describe a clearer narrative regarding Edward John Presser. Review of attainable newspaper reports framed within an historical context of fitness and relevant case law. Presser's narrative is described in greater detail than previously understood by clinicians and lawyers. Ramifications for fitness assessment are discussed including doli incapax and human rights considerations. The Presser criteria are widely applied; however, the case involved a 14-year-old boy with intellectual disability. Greater awareness of Presser's narrative assists clinicians providing expert evidence regarding fitness to plead for adolescents and persons with intellectual disability. © The Royal Australian and New Zealand College of Psychiatrists 2016.
Harden, Maegan V; Newton, Lucy A; Lloyd, Russell C; Whitlock, Kathleen E
2006-11-01
Odors experienced as juveniles can have significant effects on the behavior of mature organisms. A dramatic example of this occurs in salmon, where the odors experienced by developing fish determine the river to which they return as adults. Further examples of olfactory memories are found in many animals including vertebrates and invertebrates. Yet, the cellular and molecular bases underlying the formation of olfactory memory are poorly understood. We have devised a series of experiments to determine whether zebrafish can form olfactory memories much like those observed in salmonids. Here we show for the first time that zebrafish form and retain olfactory memories of an artificial odorant, phenylethyl alcohol (PEA), experienced as juveniles. Furthermore, we demonstrate that exposure to PEA results in changes in gene expression within the olfactory sensory system. These changes are evident by in situ hybridization in the olfactory epithelium of the developing zebrafish. Strikingly, our analysis by in situ hybridization demonstrates that the transcription factor, otx2, is up regulated in the olfactory sensory epithelia in response to PEA. This increase is evident at 2-3 days postfertilization and is maintained in the adult animals. We propose that the changes in otx2 gene expression are manifest as an increase in the number of neuronal precursors in the cells olfactory epithelium of the odor-exposed fish. Thus, our results reveal a role for the environment in controlling gene expression in the developing peripheral nervous system. Copyright 2006 Wiley Periodicals, Inc.
Autonomy, evidence and intuition: nurses and decision-making.
Traynor, Michael; Boland, Maggie; Buus, Niels
2010-07-01
This paper is a report of a study conducted to examine how nurses represent professional clinical decision-making processes, and to determine what light Jamous and Peloille's 'Indeterminacy/Technicality ratio' concept can shed on these representations. Classic definitions of professional work feature autonomy of decision-making and control over the field of work. Sociologists Jamous and Peloille have described professional work as being high in 'indeterminacy' (the use of tacit judgements) relative to technicality (activity able to be codified). The rise of the evidence-based practice movement has been seen as increasing the realm of technical decision-making in healthcare, and it is relevant to analyse nurses' professional discourse and study how they respond to this increase. Three focus groups with qualified nurses attending post-qualifying courses at a London university were held in 2008. Participants were asked to talk about influences on their decision-making. The discussions were tape-recorded, transcribed and subjected to discourse analysis. Participants described their decision-making as influenced by both indeterminate and technical features. They acknowledged useful influences from both domains, but pointed to their personal 'experience' as the final arbiter of decision-making. Their accounts of decision-making created a sense of professional autonomy while at the same time protecting it against external critique. Pre- and post-registration nurse education could encourage robust discussion of the definition and roles of 'irrational' aspects of decision-making and how these might be understood as components of credible professional practice.
Javed, Zeeshan; Qamar, Unaiza; Sathyapalan, Thozhukat
2015-01-01
There is an increasing deliberation regarding hypopituitarism following traumatic brain injury (TBI) and recent data have suggested that pituitary dysfunction is very common among survivors of patients having moderate-severe TBI which may evolve or resolve over time. Due to high prevalence of pituitary dysfunction after moderate-severe TBI and its association with increased morbidity and poor recovery and the fact that it can be easily treated with hormone replacement, it has been suggested that early detection and treatment is necessary to prevent long-term neurological consequences. The cause of pituitary dysfunction after TBI is still not well understood, but evidence suggests few possible primary and secondary causes. Results of recent studies focusing on the incidence of hypopituitarism in the acute and chronic phases after TBI are varied in terms of severity and time of occurrence. Although the literature available does not show consistent values and there is difference in study parameters and diagnostic tests used, it is clear that pituitary dysfunction is very common after moderate to severe TBI and patients should be carefully monitored. The exact timing of development cannot be predicted but has suggested regular assessment of pituitary function up to 1 year after TBI. In this narrative review, we aim to explore the current evidence available regarding the incidence of pituitary dysfunction in acute and chronic phase post-TBI and recommendations for screening and follow-up in these patients. We will also focus light over areas in this field worthy of further investigation. PMID:26693424
Abnormalities in neuroendocrine stress response in psychosis: the role of endocannabinoids.
Appiah-Kusi, E; Leyden, E; Parmar, S; Mondelli, V; McGuire, P; Bhattacharyya, S
2016-01-01
The aim of this article is to summarize current evidence regarding alterations in the neuroendocrine stress response system and endocannabinoid system and their relationship in psychotic disorders such as schizophrenia. Exposure to stress is linked to the development of a number of psychiatric disorders including psychosis. However, the precise role of stress in the development of psychosis and the possible mechanisms that might underlie this are not well understood. Recently the cannabinoid hypothesis of schizophrenia has emerged as a potential line of enquiry. Endocannabinoid levels are increased in patients with psychosis compared with healthy volunteers; furthermore, they increase in response to stress, which suggests another potential mechanism for how stress might be a causal factor in the development of psychosis. However, research regarding the links between stress and the endocannabinoid system is in its infancy. Evidence summarized here points to an alteration in the baseline tone and reactivity of the hypothalamic-pituitary-adrenal (HPA) axis as well as in various components of the endocannabinoid system in patients with psychosis. Moreover, the precise nature of the inter-relationship between these two systems is unclear in man, especially their biological relevance in the context of psychosis. Future studies need to simultaneously investigate HPA axis and endocannabinoid alterations both at baseline and following experimental perturbation in healthy individuals and those with psychosis to understand how they interact with each other in health and disease and obtain mechanistic insight as to their relevance to the pathophysiology of schizophrenia.
First macrobiota biomineralization was environmentally triggered
Ivantsov, Andrey Yu
2017-01-01
Why large and diverse skeletons first appeared ca 550 Ma is not well understood. Many Ediacaran skeletal biota show evidence of flexibility, and bear notably thin skeletal walls with simple, non-hierarchical microstructures of either aragonite or high-Mg calcite. We present evidence that the earliest skeletal macrobiota, found only in carbonate rocks, had close soft-bodied counterparts hosted in contemporary clastic rocks. This includes the calcareous discoidal fossil Suvorovella, similar to holdfasts of Ediacaran biota taxa previously known only as casts and moulds, as well as tubular and vase-shaped fossils. In sum, these probably represent taxa of diverse affinity including unicellular eukaryotes, total group cnidarians and problematica. Our findings support the assertion that the calcification was an independent and derived feature that appeared in diverse groups where an organic scaffold was the primitive character, which provided the framework for interactions between the extracellular matrix and mineral ions. We conclude that such skeletons may have been acquired with relative ease in the highly saturated, high alkalinity carbonate settings of the Ediacaran, where carbonate polymorph was further controlled by seawater chemistry. The trigger for Ediacaran biomineralization may have been either changing seawater Mg/Ca and/or increasing oxygen levels. By the Early Cambrian, however, biomineralization styles and the range of biominerals had significantly diversified, perhaps as an escalating defensive response to increasing predation pressure. Indeed skeletal hardparts had appeared in clastic settings by Cambrian Stage 1, suggesting independence from ambient seawater chemistry where genetic and molecular mechanisms controlled biomineralization and mineralogy had become evolutionarily constrained. PMID:28356454
Lags in the response of mountain plant communities to climate change
Alexander, Jake M.; Chalmandrier, Loïc; Lenoir, Jonathan; Burgess, Treena I.; Essl, Franz; Haider, Sylvia; Kueffer, Christoph; McDougall, Keith; Milbau, Ann; Nuñez, Martin A.; Pauchard, Aníbal; Rabitsch, Wolfgang; Rew, Lisa J.; Sanders, Nathan J.; Pellissier, Loïc
2018-01-01
Rapid climatic changes and increasing human influence at high elevations around the world will have profound impacts on mountain biodiversity. However, forecasts from statistical models (e.g. species distribution models) rarely consider that plant community changes could substantially lag behind climatic changes, hindering our ability to make temporally realistic projections for the coming century. Indeed, the magnitudes of lags, and the relative importance of the different factors giving rise to them, remain poorly understood. We review evidence for three types of lag: “dispersal lags” affecting plant species’ spread along elevational gradients, “establishment lags” following their arrival in recipient communities, and “extinction lags” of resident species. Variation in lags is explained by variation among species in physiological and demographic responses, by effects of altered biotic interactions, and by aspects of the physical environment. Of these, altered biotic interactions could contribute substantially to establishment and extinction lags, yet impacts of biotic interactions on range dynamics are poorly understood. We develop a mechanistic community model to illustrate how species turnover in future communities might lag behind simple expectations based on species’ range shifts with unlimited dispersal. The model shows a combined contribution of altered biotic interactions and dispersal lags to plant community turnover along an elevational gradient following climate warming. Our review and simulation support the view that accounting for disequilibrium range dynamics will be essential for realistic forecasts of patterns of biodiversity under climate change, with implications for the conservation of mountain species and the ecosystem functions they provide. PMID:29112781
USDA-ARS?s Scientific Manuscript database
Atmospheric CO2 concentration will likely exceed 500 uL L-1 by 2050, often increasing plant community productivity in part by increasing abundance of species favored by increased CA. Whether increased abundance translates to increased inflorescence production is poorly understood, and is important ...
The relationship between gut and adipose hormones, and reproduction.
Comninos, Alexander N; Jayasena, Channa N; Dhillo, Waljit S
2014-01-01
Reproductive function is tightly regulated by nutritional status. Indeed, it has been well described that undernutrition or obesity can lead to subfertility or infertility in humans. The common regulatory pathways which control energy homeostasis and reproductive function have, to date, been poorly understood due to limited studies or inconclusive data. However, gut hormones and adipose tissue hormones have recently emerged as potential regulators of both energy homeostasis and reproductive function. A PubMed search was performed using keywords related to gut and adipose hormones and associated with keywords related to reproduction. Currently available evidence that gut (ghrelin, obestatin, insulin, peptide YY, glucagon-like peptide-1, glucose-dependent insulinotropic peptide, oxyntomodulin, cholecystokinin) and adipose hormones (leptin, adiponectin, resistin, omentin, chemerin) interact with the reproductive axis is presented. The extent, site and direction of their effects on the reproductive axis are variable and also vary depending on species, sex and pubertal stage. Gut and adipose hormones interact with the reproductive axis as well as with each other. While leptin and insulin have stimulatory effects and ghrelin has inhibitory effects on hypothalamic GnRH secretion, there is increasing evidence for their roles in other sites of the reproductive axis as well as evidence for the roles of other gut and adipose hormones in the complex interplay between nutrition and reproduction. As our understanding improves, so will our ability to identify and design novel therapeutic options for reproductive disorders and accompanying metabolic disorders.
A pragmatic evidence-based clinical management algorithm for burning mouth syndrome.
Kim, Yohanan; Yoo, Timothy; Han, Peter; Liu, Yuan; Inman, Jared C
2018-04-01
Burning mouth syndrome is a poorly understood disease process with no current standard of treatment. The goal of this article is to provide an evidence-based, practical, clinical algorithm as a guideline for the treatment of burning mouth syndrome. Using available evidence and clinical experience, a multi-step management algorithm was developed. A retrospective cohort study was then performed, following STROBE statement guidelines, comparing outcomes of patients who were managed using the algorithm and those who were managed without. Forty-seven patients were included in the study, with 21 (45%) managed using the algorithm and 26 (55%) managed without. The mean age overall was 60.4 ±16.5 years, and most patients (39, 83%) were female. Cohorts showed no statistical difference in age, sex, overall follow-up time, dysgeusia, geographic tongue, or psychiatric disorder; xerostomia, however, was significantly different, skewed toward the algorithm group. Significantly more non-algorithm patients did not continue care (69% vs. 29%, p =0.001). The odds ratio of not continuing care for the non-algorithm group compared to the algorithm group was 5.6 [1.6, 19.8]. Improvement in pain was significantly more likely in the algorithm group ( p =0.001), with an odds ratio of 27.5 [3.1, 242.0]. We present a basic clinical management algorithm for burning mouth syndrome which may increase the likelihood of pain improvement and patient follow-up. Key words: Burning mouth syndrome, burning tongue, glossodynia, oral pain, oral burning, therapy, treatment.
Geophysical, archaeological, and historical evidence support a solar-output model for climate change
Perry, Charles A.; Hsu, Kenneth J.
2000-01-01
Although the processes of climate change are not completely understood, an important causal candidate is variation in total solar output. Reported cycles in various climate-proxy data show a tendency to emulate a fundamental harmonic sequence of a basic solar-cycle length (11 years) multiplied by 2N (where N equals a positive or negative integer). A simple additive model for total solar-output variations was developed by superimposing a progression of fundamental harmonic cycles with slightly increasing amplitudes. The timeline of the model was calibrated to the Pleistocene/Holocene boundary at 9,000 years before present. The calibrated model was compared with geophysical, archaeological, and historical evidence of warm or cold climates during the Holocene. The evidence of periods of several centuries of cooler climates worldwide called “little ice ages,” similar to the period anno Domini (A.D.) 1280–1860 and reoccurring approximately every 1,300 years, corresponds well with fluctuations in modeled solar output. A more detailed examination of the climate sensitive history of the last 1,000 years further supports the model. Extrapolation of the model into the future suggests a gradual cooling during the next few centuries with intermittent minor warmups and a return to near little-ice-age conditions within the next 500 years. This cool period then may be followed approximately 1,500 years from now by a return to altithermal conditions similar to the previous Holocene Maximum. PMID:11050181
Potential Role of the Gut Microbiome in ALS: A Systematic Review.
Wright, Michelle L; Fournier, Christina; Houser, Madelyn C; Tansey, Malú; Glass, Jonathan; Hertzberg, Vicki Stover
2018-01-01
Amyotrophic lateral sclerosis (ALS) etiology and pathophysiology are not well understood. Recent data suggest that dysbiosis of gut microbiota may contribute to ALS etiology and progression. This review aims to explore evidence of associations between gut microbiota and ALS etiology and pathophysiology. Databases were searched for publications relevant to the gut microbiome in ALS. Three publications provided primary evidence of changes in microbiome profiles in ALS. An ALS mouse model revealed damaged tight junction structure and increased permeability in the intestine versus controls along with a shifted microbiome profile, including decreased levels of butyrate-producing bacteria. In a subsequent publication, again using an ALS mouse model, researchers showed that dietary supplementation with butyrate relieved symptoms and lengthened both time to onset of weight loss and survival time. In a small study of ALS patients and healthy controls, investigators also found decreased levels of butyrate-producing bacteria. Essential for maintaining gut barrier integrity, butyrate is the preferred energy source of intestinal epithelial cells. Ten other articles were reviews and commentaries providing indirect support for a role of gut microbiota in ALS pathophysiology. Thus, these studies provide a modicum of evidence implicating gut microbiota in ALS disease, although more research is needed to confirm the connection and determine pathophysiologic mechanisms. Nurses caring for these patients need to understand the gut microbiome and its potential role in ALS in order to effectively counsel patients and their families about emerging therapies (e.g., prebiotics, probiotics, and fecal microbial transplant) and their off-label uses.
Biological evidence supports an early and complex emergence of the Isthmus of Panama
Bacon, Christine D.; Silvestro, Daniele; Jaramillo, Carlos; Smith, Brian Tilston; Chakrabarty, Prosanta; Antonelli, Alexandre
2015-01-01
The linking of North and South America by the Isthmus of Panama had major impacts on global climate, oceanic and atmospheric currents, and biodiversity, yet the timing of this critical event remains contentious. The Isthmus is traditionally understood to have fully closed by ca. 3.5 million years ago (Ma), and this date has been used as a benchmark for oceanographic, climatic, and evolutionary research, but recent evidence suggests a more complex geological formation. Here, we analyze both molecular and fossil data to evaluate the tempo of biotic exchange across the Americas in light of geological evidence. We demonstrate significant waves of dispersal of terrestrial organisms at approximately ca. 20 and 6 Ma and corresponding events separating marine organisms in the Atlantic and Pacific oceans at ca. 23 and 7 Ma. The direction of dispersal and their rates were symmetrical until the last ca. 6 Ma, when northern migration of South American lineages increased significantly. Variability among taxa in their timing of dispersal or vicariance across the Isthmus is not explained by the ecological factors tested in these analyses, including biome type, dispersal ability, and elevation preference. Migration was therefore not generally regulated by intrinsic traits but more likely reflects the presence of emergent terrain several millions of years earlier than commonly assumed. These results indicate that the dramatic biotic turnover associated with the Great American Biotic Interchange was a long and complex process that began as early as the Oligocene–Miocene transition. PMID:25918375
Cantor, J
2000-08-01
Research on the effects of media violence is not well understood by the general public. Despite this fact, there is an overwhelming consensus in the scientific literature about the unhealthy effects of media violence. Meta-analyses show that media-violence viewing consistently is associated with higher levels of antisocial behavior, ranging from the trivial (imitative violence directed against toys) to the serious (criminal violence), with many consequential outcomes in between (acceptance of violence as a solution to problems, increased feelings of hostility, and the apparent delivery of painful stimulation to another person). Desensitization is another well-documented effect of viewing violence, which is observable in reduced arousal and emotional disturbance while witnessing violence, the reduced tendency to intervene in a fight, and less sympathy for the victims of violence. Although there is evidence that youth who are already violent are more likely to seek out violent entertainment, there is strong evidence that the relationship between violence viewing and antisocial behavior is bidirectional. There is growing evidence that media violence also engenders intense fear in children which often lasts days, months, and even years. The media's potential role in solutions to these problems is only beginning to be explored, in investigations examining the uses and effects of movie ratings, television ratings, and the V-chip, and the effects of media literacy programs and public education efforts. Future research should explore important individual differences in responses to media violence and effective ways to intervene in the negative effects.
Addressing the vaccine confidence gap.
Larson, Heidi J; Cooper, Louis Z; Eskola, Juhani; Katz, Samuel L; Ratzan, Scott
2011-08-06
Vaccines--often lauded as one of the greatest public health interventions--are losing public confidence. Some vaccine experts have referred to this decline in confidence as a crisis. We discuss some of the characteristics of the changing global environment that are contributing to increased public questioning of vaccines, and outline some of the specific determinants of public trust. Public decision making related to vaccine acceptance is neither driven by scientific nor economic evidence alone, but is also driven by a mix of psychological, sociocultural, and political factors, all of which need to be understood and taken into account by policy and other decision makers. Public trust in vaccines is highly variable and building trust depends on understanding perceptions of vaccines and vaccine risks, historical experiences, religious or political affiliations, and socioeconomic status. Although provision of accurate, scientifically based evidence on the risk-benefit ratios of vaccines is crucial, it is not enough to redress the gap between current levels of public confidence in vaccines and levels of trust needed to ensure adequate and sustained vaccine coverage. We call for more research not just on individual determinants of public trust, but on what mix of factors are most likely to sustain public trust. The vaccine community demands rigorous evidence on vaccine efficacy and safety and technical and operational feasibility when introducing a new vaccine, but has been negligent in demanding equally rigorous research to understand the psychological, social, and political factors that affect public trust in vaccines. Copyright © 2011 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Criss, Amy H.; Malmberg, Kenneth J.
2008-01-01
One of the most studied and least well understood phenomena in episodic memory is the word frequency effect (WFE). The WFE is expressed as a mirror pattern where uncommon low frequency words (LF) are better recognized than common high frequency words (HF) by way of a higher HR and lower FAR. One explanation for the HR difference is the early-phase…
ERIC Educational Resources Information Center
Fugard, Andrew J. B.; Stewart, Mary E.; Stenning, Keith
2011-01-01
People with autism spectrum condition (ASC) perform well on Raven's matrices, a test which loads highly on the general factor in intelligence. However, the mechanisms supporting enhanced performance on the test are poorly understood. Evidence is accumulating that milder variants of the ASC phenotype are present in typically developing individuals,…
State of the Art of Natural Language Processing
1987-11-15
work of Chomsky , Hewlett-Packard, Generalized Phase Structure Grammar . D. Lunar, DARPA speech understanding, Schank’s Conceptual Dependency Theory...of computers that a machine which understood natural languages was highly desirable. It also was evident from the work of Chomsky * and others that...computers. ♦Noam Chomsky , Aspects of the Theory of Syntax (Cambridge, Mass.: MIT Press, 1965). -A- One of the earliest attempts at Natural Language
ERIC Educational Resources Information Center
Pitchford, Nicola; Johnson, Samantha; Scerif, Gaia; Marlow, Neil
2011-01-01
Cognitive impairment often follows preterm birth but its early underlying nature is not well understood. We used a novel approach by investigating the development of colour cognition in 54 very preterm children born less than or equal to 30 weeks gestational age without severe neurosensory impairment and 37 age-matched term-born controls, aged 2-5…
Jastifer, James; Kent, Richard; Crandall, Jeff; Sherwood, Chris; Lessley, David; McCullough, Kirk A.; Coughlin, Michael J.; Anderson, Robert B.
2017-01-01
Background: Foot and ankle injuries are common in sports, particularly in cleated athletes. Traditionally, the athletic shoe has not been regarded as a piece of protective equipment but rather as a part of the uniform, with a primary focus on performance and subjective feedback measures of comfort. Changes in turf and shoe design have poorly understood implications on the health and safety of players. Evidence Acquisition: A literature search of the MEDLINE and PubMed databases was conducted. Keywords included athletic shoewear, cleated shoe, football shoes, and shoewear, and search parameters were between the years 2000 and 2016. Study Design: Clinical review. Level of Evidence: Level 5. Results: The athletic shoe is an important piece of protective sports equipment. There are several important structural considerations of shoe design, including biomechanical compliance, cleat and turf interaction, and shoe sizing/fit, that affect the way an athlete engages with the playing surface and carry important potential implications regarding player safety if not understood and addressed. Conclusion: Athletic footwear should be considered an integral piece of protective equipment rather than simply an extension of the uniform apparel. More research is needed to define optimal shoe sizing, the effect that design has on mechanical load, and how cleat properties, including pattern and structure, interact with the variety of playing surfaces. PMID:28151702
Tillage-induced short-term soil organic matter turnover and respiration
NASA Astrophysics Data System (ADS)
Fiedler, Sebastian Rainer; Leinweber, Peter; Jurasinski, Gerald; Eckhardt, Kai-Uwe; Glatzel, Stephan
2016-09-01
Tillage induces decomposition and mineralisation of soil organic matter (SOM) by the disruption of macroaggregates and may increase soil CO2 efflux by respiration, but these processes are not well understood at the molecular level. We sampled three treatments (mineral fertiliser: MF; biogas digestate: BD; unfertilised control: CL) of a Stagnic Luvisol a few hours before and directly after tillage as well as 4 days later from a harvested maize field in northern Germany and investigated these samples by means of pyrolysis-field ionisation mass spectrometry (Py-FIMS) and hot-water extraction. Before tillage, the Py-FIMS mass spectra revealed differences in relative ion intensities of MF and CL compared to BD most likely attributable to the cattle manure used for the biogas feedstock and to relative enrichments during anaerobic fermentation. After tillage, the CO2 effluxes were increased in all treatments, but this increase was less pronounced in BD. We explain this by restricted availability of readily biodegradable carbon compounds and possibly an inhibitory effect of sterols from digestates. Significant changes in SOM composition were observed following tillage. In particular, lignin decomposition and increased proportions of N-containing compounds were detected in BD. In MF, lipid proportions increased at the expense of ammonia, ammonium, carbohydrates and peptides, indicating enhanced microbial activity. SOM composition in CL was unaffected by tillage. Our analyses provide strong evidence for significant short-term SOM changes due to tillage in fertilised soils.
Effect of energetic electrons on combustion of premixed burner flame
NASA Astrophysics Data System (ADS)
Sasaki, Koichi
2011-10-01
In many studies of plasma-assisted combustion, authors superpose discharges onto flames to control combustion reactions. This work is motivated by more fundamental point of view. The standpoint of this work is that flames themselves are already plasmas. We irradiated microwave power onto premixed burner flame with the intention of heating electrons in it. The microwave power was limited below the threshold for a discharge. We obtained the enhancement of burning velocity by the irradiation of the microwave power, which was understood by the shortening of the flame length. At the same time, we observed the increases in the optical emission intensities of OH and CH radicals. Despite the increases in the optical emission intensities, the optical emission spectra of OH and CH were not affected by the microwave irradiation, indicating that the enhancement of the burning velocity was not attributed to the increase in the gas temperature. On the other hand, we observed significant increase in the optical emission intensity of the second positive system of molecular nitrogen, which is a clear evidence for electron heating in the premixed burner flame. Therefore, it is considered that the enhancement of the burning velocity is obtained by nonequilibrium combustion chemistry which is driven by energetic electrons. By irradiating pulsed microwave power, we examined the time constants for the increases and decreases in the optical emission intensities of N2, OH, CH, and continuum radiation.
NASA Astrophysics Data System (ADS)
Chikozho, C.; Danga, L.; Saruchera, D.
2017-08-01
Governance of the water sector in South Africa has reflected the political changes taking place in society. For instance, due to apartheid policies of segregation, inequality of access to water resources marks South Africa's history in a very profound way and redistribution of rights to water to redress the results of past discrimination became an explicit purpose of the post-apartheid water governance policy and legislative regime. In this paper, we articulate the history and major departure points evident in post-apartheid South African national water policy and law. This includes documenting and reflecting on most of the available information that shows how the new water policy and law were developed. Findings from the study show that the key players active in the water law review process deliberately took into account the political goals and dynamics of power asymmetry within which the law was being articulated. Therefore, the water law as it stands today and in the past must be understood within the context of the socio-economic and political landscape that has prevailed in South Africa at different historical junctures. We contend that a detailed examination and articulation of the history and major departure points evident in post-apartheid South African national water policy and law enables practitioners and scholars to better understand the main motivations behind the water sector reforms and the then prevailing thinking behind the policy and legislation eventually promulgated. The present water law must be understood in the context of these reforms and the objectives they sought to achieve.
Long-Term PM2.5 Exposure and Respiratory, Cancer, and Cardiovascular Mortality in Older US Adults.
Pun, Vivian C; Kazemiparkouhi, Fatemeh; Manjourides, Justin; Suh, Helen H
2017-10-15
The impact of chronic exposure to fine particulate matter (particulate matter with an aerodynamic diameter less than or equal to 2.5 μm (PM2.5)) on respiratory disease and lung cancer mortality is poorly understood. In a cohort of 18.9 million Medicare beneficiaries (4.2 million deaths) living across the conterminous United States between 2000 and 2008, we examined the association between chronic PM2.5 exposure and cause-specific mortality. We evaluated confounding through adjustment for neighborhood behavioral covariates and decomposition of PM2.5 into 2 spatiotemporal scales. We found significantly positive associations of 12-month moving average PM2.5 exposures (per 10-μg/m3 increase) with respiratory, chronic obstructive pulmonary disease, and pneumonia mortality, with risk ratios ranging from 1.10 to 1.24. We also found significant PM2.5-associated elevated risks for cardiovascular and lung cancer mortality. Risk ratios generally increased with longer moving averages; for example, an elevation in 60-month moving average PM2.5 exposures was linked to 1.33 times the lung cancer mortality risk (95% confidence interval: 1.24, 1.40), as compared with 1.13 (95% confidence interval: 1.11, 1.15) for 12-month moving average exposures. Observed associations were robust in multivariable models, although evidence of unmeasured confounding remained. In this large cohort of US elderly, we provide important new evidence that long-term PM2.5 exposure is significantly related to increased mortality from respiratory disease, lung cancer, and cardiovascular disease. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
The late Middle Pleistocene hominin fossil record of eastern Asia: synthesis and review.
Bae, Christopher J
2010-01-01
Traditionally, Middle Pleistocene hominin fossils that cannot be allocated to Homo erectus sensu lato or modern H. sapiens have been assigned to different specific taxa. For example, in eastern Asia, these hominin fossils have been classified as archaic, early, or premodern H. sapiens. An increasing number of Middle Pleistocene hominin fossils are currently being assigned to H. heidelbergensis. This is particularly the case for the African and European Middle Pleistocene hominin fossil record. There have been suggestions that perhaps the eastern Asian late Middle Pleistocene hominins can also be allocated to the H. heidelbergensis hypodigm. In this article, I review the current state of the late Middle Pleistocene hominin fossil record from eastern Asia and examine the various arguments for assigning these hominins to the different specific taxa. The two primary conclusions drawn from this review are as follows: 1) little evidence currently exists in the eastern Asian Middle Pleistocene hominin fossil record to support their assignment to H. heidelbergensis; and 2) rather than add to the growing list of hominin fossil taxa by using taxonomic names like H. daliensis for northeast Asian fossils and H. mabaensis for Southeast Asian fossils, it is better to err on the side of caution and continue to use the term archaic H. sapiens to represent all of these hominin fossils. What should be evident from this review is the need for an increase in the quality and quantity of the eastern Asian hominin fossil data set. Fortunately, with the increasing number of large-scale multidisciplinary paleoanthropological field and laboratory research projects in eastern Asia, the record is quickly becoming better understood. Copyright © 2010 Wiley-Liss, Inc.
Migraine increases centre-surround suppression for drifting visual stimuli.
Battista, Josephine; Badcock, David R; McKendrick, Allison M
2011-04-11
The pathophysiology of migraine is incompletely understood, but evidence points to hyper-responsivity of cortical neurons being a key feature. The basis of hyper-responsiveness is not clear, with an excitability imbalance potentially arising from either reduced inhibition or increased excitation. In this study, we measure centre-surround contrast suppression in people with migraine as a perceptual analogue of the interplay between inhibition and excitation in cortical areas responsible for vision. We predicted that reduced inhibitory function in migraine would reduce perceptual surround suppression. Recent models of neuronal surround suppression incorporate excitatory feedback that drives surround inhibition. Consequently, an increase in excitation predicts an increase in perceptual surround suppression. Twenty-six people with migraine and twenty approximately age- and gender-matched non-headache controls participated. The perceived contrast of a central sinusoidal grating patch (4 c/deg stationary grating, or 2 c/deg drifting at 2 deg/sec, 40% contrast) was measured in the presence and absence of a 95% contrast annular grating (same orientation, spatial frequency, and drift rate). For the static grating, similar surround suppression strength was present in control and migraine groups with the presence of the surround resulting in the central patch appearing to be 72% and 65% of its true contrast for control and migraine groups respectively (t(44) = 0.81, p = 0.42). For the drifting stimulus, the migraine group showed significantly increased surround suppression (t(44) = 2.86, p<0.01), with perceived contrast being on average 53% of actual contrast for the migraine group and 68% for non-headache controls. In between migraines, when asymptomatic, visual surround suppression for drifting stimuli is greater in individuals with migraine than in controls. The data provides evidence for a behaviourally measurable imbalance in inhibitory and excitatory visual processes in migraine and is incompatible with a simple model of reduced cortical inhibitory function within the visual system.
Sanchez, Mar M; McCormack, Kai M; Howell, Brittany R
2015-01-01
Social buffering, the phenomenon by which the presence of a familiar individual reduces or even eliminates stress- and fear-induced responses, exists in different animal species and has been examined in the context of the mother-infant relationship, in addition to adults. Although it is a well-known effect, the biological mechanisms that underlie it as well as its developmental impact are not well understood. Here, we provide a review of evidence of social and maternal buffering of stress reactivity in nonhuman primates, and some data from our group suggesting that when the mother-infant relationship is disrupted, maternal buffering is impaired. This evidence underscores the critical role that maternal care plays for proper regulation and development of emotional and stress responses of primate infants. Disruptions of the parent-infant bond constitute early adverse experiences associated with increased risk for psychopathology. We will focus on infant maltreatment, a devastating experience not only for humans, but for nonhuman primates as well. Taking advantage of this naturalistic animal model of adverse maternal caregiving, we have shown that competent maternal care is critical for the development of healthy attachment, social behavior, and emotional and stress regulation, as well as of the neural circuits underlying these functions.
The evolution and genetics of cerebral asymmetry
Corballis, Michael C.
2008-01-01
Handedness and cerebral asymmetry are commonly assumed to be uniquely human, and even defining characteristics of our species. This is increasingly refuted by the evidence of behavioural asymmetries in non-human species. Although complex manual skill and language are indeed unique to our species and are represented asymmetrically in the brain, some non-human asymmetries appear to be precursors, and others are shared between humans and non-humans. In all behavioural and cerebral asymmetries so far investigated, a minority of individuals reverse or negate the dominant asymmetry, suggesting that such asymmetries are best understood in the context of the overriding bilateral symmetry of the brain and body, and a trade-off between the relative advantages and disadvantages of symmetry and asymmetry. Genetic models of handedness, for example, typically postulate a gene with two alleles, one disposing towards right-handedness and the other imposing no directional influence. There is as yet no convincing evidence as to the location of this putative gene, suggesting that several genes may be involved, or that the gene may be monomorphic with variations due to environmental or epigenetic influences. Nevertheless, it is suggested that, in behavioural, neurological and evolutionary terms, it may be more profitable to examine the degree rather than the direction of asymmetry. PMID:19064358
Thermal acclimation mitigates cold-induced paracellular leak from the Drosophila gut.
MacMillan, Heath A; Yerushalmi, Gil Y; Jonusaite, Sima; Kelly, Scott P; Donini, Andrew
2017-08-18
Chill susceptible insects suffer tissue damage and die at low temperatures. The mechanisms that cause chilling injury are not well understood but a growing body of evidence suggests that a cold-induced loss of ion and water homeostasis leads to hemolymph hyperkalemia that depolarizes cells, leading to cell death. The apparent root of this cascade is the net leak of osmolytes down their concentration gradients in the cold. Many insects, however, are capable of adjusting their thermal physiology, and cold-acclimated Drosophila can maintain homeostasis and avoid injury better than warm-acclimated flies. Here, we test whether chilling causes a loss of epithelial barrier function in female adult Drosophila, and provide the first evidence of cold-induced epithelial barrier failure in an invertebrate. Flies had increased rates of paracellular leak through the gut epithelia at 0 °C, but cold acclimation reduced paracellular permeability and improved cold tolerance. Improved barrier function was associated with changes in the abundance of select septate junction proteins and the appearance of a tortuous ultrastructure in subapical intercellular regions of contact between adjacent midgut epithelial cells. Thus, cold causes paracellular leak in a chill susceptible insect and cold acclimation can mitigate this effect through changes in the composition and structure of transepithelial barriers.
Comparative effectiveness and cost-effectiveness analyses frequently agree on value.
Glick, Henry A; McElligott, Sean; Pauly, Mark V; Willke, Richard J; Bergquist, Henry; Doshi, Jalpa; Fleisher, Lee A; Kinosian, Bruce; Perfetto, Eleanor; Polsky, Daniel E; Schwartz, J Sanford
2015-05-01
The Patient-Centered Outcomes Research Institute, known as PCORI, was established by Congress as part of the Affordable Care Act (ACA) to promote evidence-based treatment. Provisions of the ACA prohibit the use of a cost-effectiveness analysis threshold and quality-adjusted life-years (QALYs) in PCORI comparative effectiveness studies, which has been understood as a prohibition on support for PCORI's conducting conventional cost-effectiveness analyses. This constraint complicates evidence-based choices where incremental improvements in outcomes are achieved at increased costs of care. How frequently this limitation inhibits efficient cost containment, also a goal of the ACA, depends on how often more effective treatment is not cost-effective relative to less effective treatment. We examined the largest database of studies of comparisons of effectiveness and cost-effectiveness to see how often there is disagreement between the more effective treatment and the cost-effective treatment, for various thresholds that may define good value. We found that under the benchmark assumption, disagreement between the two types of analyses occurs in 19 percent of cases. Disagreement is more likely to occur if a treatment intervention is musculoskeletal and less likely to occur if it is surgical or involves secondary prevention, or if the study was funded by a pharmaceutical company. Project HOPE—The People-to-People Health Foundation, Inc.
Akob, Denise M.; Mumford, Adam; Orem, William H.; Engle, Mark A.; Klinges, Julia (Grace); Kent, Douglas B.; Cozzarelli, Isabelle M.
2016-01-01
The development of unconventional oil and gas (UOG) resources has rapidly increased in recent years; however, the environmental impacts and risks are poorly understood. A single well can generate millions of liters of wastewater, representing a mixture of formation brine and injected hydraulic fracturing fluids. One of the most common methods for wastewater disposal is underground injection; we are assessing potential risks of this method through an intensive, interdisciplinary study at an injection disposal facility in West Virginia. In June 2014, waters collected downstream from the site had elevated specific conductance (416 μS/cm) and Na, Cl, Ba, Br, Sr, and Li concentrations, compared to upstream, background waters (conductivity, 74 μS/cm). Elevated TDS, a marker of UOG wastewater, provided an early indication of impacts in the stream. Wastewater inputs are also evident by changes in 87Sr/86Sr in streamwater adjacent to the disposal facility. Sediments downstream from the facility were enriched in Ra and had high bioavailable Fe(III) concentrations relative to upstream sediments. Microbial communities in downstream sediments had lower diversity and shifts in composition. Although the hydrologic pathways were not able to be assessed, these data provide evidence demonstrating that activities at the disposal facility are impacting a nearby stream and altering the biogeochemistry of nearby ecosystems.
McCormack, Kai M.; Howell, Brittany R.
2015-01-01
Social buffering, the phenomenon by which the presence of a familiar individual reduces or even eliminates stress- and fear-induced responses exists in different animal species, and has been examined in the context of the mother-infant relationship in addition to adults. Although it is a well-known effect, the biological mechanisms, which underlie it, as well as its developmental impact are not well understood. Here we provide a review of evidence of social and maternal buffering of stress reactivity in nonhuman primates, and some data from our group suggesting that when the mother-infant relationship is disrupted maternal buffering is impaired. This evidence underscores the critical role that maternal care plays for proper regulation and development of emotional and stress responses of primate infants. Disruptions of the parent-infant bond constitute early adverse experiences associated with increased risk for psychopathology. We will focus on infant maltreatment, a devastating experience not only for humans, but for nonhuman primates as well. Taking advantage of this naturalistic animal model of adverse maternal caregiving we have shown that competent maternal care is critical for the development of healthy attachment, social behavior and emotional and stress regulation, as well as of neural circuits underlying these functions. PMID:26324227
Variations in gestational length and preterm delivery by race, ethnicity and migration.
Sørbye, Ingvil K; Wanigaratne, Susitha; Urquia, Marcelo L
2016-04-01
Preterm delivery rates within industrialized countries have been reported to vary according to the parents' race, ethnicity and migrant status; however, such disparities are poorly understood. In this paper, the available evidence and potential clinical significance of racial/ethnic and migrant disparities in gestational length and preterm delivery are assessed alongside potential explanatory factors. Although measurement bias in gestational length has the potential to inflate disparities, there is a consistently higher risk of preterm birth among some racial/ethnic groups. These differences most likely reflect lasting socio-economic disadvantage and discrimination rather than genetic mechanisms. The effect of migrant status is less conclusive due to heterogeneity of populations and the healthy migrant effect; however, environmental influences in the receiving country are implicated in driving increases of overall preterm rates. When assessing preterm delivery rates across ethnic and migrant groups, the use of standardized, ultrasound-based pregnancy dating methods is crucial to minimize bias. Current evidence does not justify the provision of a different clinical care approach to minority or immigrant women solely based on their race, ethnicity or country of origin; however, these labels may serve as flags for further inquiry on individual risk factors and a detailed obstetric history. Copyright © 2015 Elsevier Ltd. All rights reserved.
Neural Plasticity in Multiple Sclerosis: The Functional and Molecular Background
Glabinski, Andrzej
2015-01-01
Multiple sclerosis is an autoimmune neurodegenerative disorder resulting in motor dysfunction and cognitive decline. The inflammatory and neurodegenerative changes seen in the brains of MS patients lead to progressive disability and increasing brain atrophy. The most common type of MS is characterized by episodes of clinical exacerbations and remissions. This suggests the presence of compensating mechanisms for accumulating damage. Apart from the widely known repair mechanisms like remyelination, another important phenomenon is neuronal plasticity. Initially, neuroplasticity was connected with the developmental stages of life; however, there is now growing evidence confirming that structural and functional reorganization occurs throughout our lifetime. Several functional studies, utilizing such techniques as fMRI, TBS, or MRS, have provided valuable data about the presence of neuronal plasticity in MS patients. CNS ability to compensate for neuronal damage is most evident in RR-MS; however it has been shown that brain plasticity is also preserved in patients with substantial brain damage. Regardless of the numerous studies, the molecular background of neuronal plasticity in MS is still not well understood. Several factors, like IL-1β, BDNF, PDGF, or CB1Rs, have been implicated in functional recovery from the acute phase of MS and are thus considered as potential therapeutic targets. PMID:26229689
Jobes, David A
2012-12-01
The Collaborative Assessment and Management of Suicidality (CAMS) is an evidence-based clinical intervention that has significantly evolved over 25 years of clinical research. CAMS is best understood as a therapeutic framework that emphasizes a unique collaborative assessment and treatment planning process between the suicidal patient and clinician. This process is designed to enhance the therapeutic alliance and increase treatment motivation in the suicidal patient. Central to the CAMS approach is the use of the Suicide Status Form (SSF), which is a multipurpose clinical assessment, treatment planning, tracking, and outcome tool. The original development of CAMS was largely rooted in SSF-based quantitative and qualitative assessment of suicidal risk. As this line of research progressed, CAMS emerged as a problem-focused clinical intervention that is designed to target and treat suicidal "drivers" and ultimately eliminate suicidal coping. To date, CAMS (and the clinical use of the SSF) has been supported by six published correlational studies and one randomized clinical trial (RCT). Currently, two well-powered RCTs are under way, and various new CAMS-related projects are also being pursued. The clinical and empirical evolution of CAMS-how it was developed and what are the next steps for this clinical approach-are described here. © 2012 The American Association of Suicidology.
Corbett-Detig, Russell B.
2016-01-01
Chromosomal inversions are widespread among taxa, and have been implicated in a number of biological processes including adaptation, sex chromosome evolution, and segregation distortion. Consistent with selection favoring linkage between loci, it is well established that length is a selected trait of inversions. However, the factors that affect the distribution of inversion breakpoints remain poorly understood. “Sensitive sites” have been mapped on all euchromatic chromosome arms in Drosophila melanogaster, and may be a source of natural selection on inversion breakpoint positions. Briefly, sensitive sites are genomic regions wherein proximal structural rearrangements result in large reductions in local recombination rates in heterozygotes. Here, I show that breakpoints of common inversions are significantly more likely to lie within a cytological band containing a sensitive site than are breakpoints of rare inversions. Furthermore, common inversions for which neither breakpoint intersects a sensitive site are significantly longer than rare inversions, but common inversions whose breakpoints intersect a sensitive site show no evidence for increased length. I interpret these results to mean that selection favors inversions whose breakpoints disrupt synteny near to sensitive sites, possibly because these inversions suppress recombination in large genomic regions. To my knowledge this is the first evidence consistent with positive selection acting on inversion breakpoint positions. PMID:27343234
Corbett-Detig, Russell B
2016-09-01
Chromosomal inversions are widespread among taxa, and have been implicated in a number of biological processes including adaptation, sex chromosome evolution, and segregation distortion. Consistent with selection favoring linkage between loci, it is well established that length is a selected trait of inversions. However, the factors that affect the distribution of inversion breakpoints remain poorly understood. "Sensitive sites" have been mapped on all euchromatic chromosome arms in Drosophila melanogaster, and may be a source of natural selection on inversion breakpoint positions. Briefly, sensitive sites are genomic regions wherein proximal structural rearrangements result in large reductions in local recombination rates in heterozygotes. Here, I show that breakpoints of common inversions are significantly more likely to lie within a cytological band containing a sensitive site than are breakpoints of rare inversions. Furthermore, common inversions for which neither breakpoint intersects a sensitive site are significantly longer than rare inversions, but common inversions whose breakpoints intersect a sensitive site show no evidence for increased length. I interpret these results to mean that selection favors inversions whose breakpoints disrupt synteny near to sensitive sites, possibly because these inversions suppress recombination in large genomic regions. To my knowledge this is the first evidence consistent with positive selection acting on inversion breakpoint positions. Copyright © 2016 by the Genetics Society of America.
2017-01-01
The type and variety of learning strategies used by individuals to acquire behaviours in the wild are poorly understood, despite the presence of behavioural traditions in diverse taxa. Social learning strategies such as conformity can be broadly adaptive, but may also retard the spread of adaptive innovations. Strategies like pay-off-biased learning, by contrast, are effective at diffusing new behaviour but may perform poorly when adaptive behaviour is common. We present a field experiment in a wild primate, Cebus capucinus, that introduced a novel food item and documented the innovation and diffusion of successful extraction techniques. We develop a multilevel, Bayesian statistical analysis that allows us to quantify individual-level evidence for different social and individual learning strategies. We find that pay-off-biased and age-biased social learning are primarily responsible for the diffusion of new techniques. We find no evidence of conformity; instead rare techniques receive slightly increased attention. We also find substantial and important variation in individual learning strategies that is patterned by age, with younger individuals being more influenced by both social information and their own individual experience. The aggregate cultural dynamics in turn depend upon the variation in learning strategies and the age structure of the wild population. PMID:28592681
The Demise of the Synapse As the Locus of Memory: A Looming Paradigm Shift?
Trettenbrein, Patrick C
2016-01-01
Synaptic plasticity is widely considered to be the neurobiological basis of learning and memory by neuroscientists and researchers in adjacent fields, though diverging opinions are increasingly being recognized. From the perspective of what we might call "classical cognitive science" it has always been understood that the mind/brain is to be considered a computational-representational system. Proponents of the information-processing approach to cognitive science have long been critical of connectionist or network approaches to (neuro-)cognitive architecture, pointing to the shortcomings of the associative psychology that underlies Hebbian learning as well as to the fact that synapses are practically unfit to implement symbols. Recent work on memory has been adding fuel to the fire and current findings in neuroscience now provide first tentative neurobiological evidence for the cognitive scientists' doubts about the synapse as the (sole) locus of memory in the brain. This paper briefly considers the history and appeal of synaptic plasticity as a memory mechanism, followed by a summary of the cognitive scientists' objections regarding these assertions. Next, a variety of tentative neuroscientific evidence that appears to substantiate questioning the idea of the synapse as the locus of memory is presented. On this basis, a novel way of thinking about the role of synaptic plasticity in learning and memory is proposed.
Current knowledge on Mycobacterium leprae transmission: a systematic literature review.
Bratschi, Martin W; Steinmann, Peter; Wickenden, Anna; Gillis, Thomas P
2015-06-01
Summary The transmission pathways of Mycobacterium leprae are not fully understood. Solid evidence exists for an increased risk for individuals living in close contact with leprosy patients but the existence of zoonotic leprosy, environmental reservoirs and trauma-related transmission has also been established. To assess the current state of knowledge on M. leprae transmission, we conducted a systematic review of the peer-reviewed literature pertaining to this topic. Major electronic bibliographic databases were searched for relevant peer-reviewed articles published up to January 2014. No restrictions on study types, participants and location were applied, and all outcomes demonstrated to contribute to the transmission of M. leprae were considered. Included studies were grouped by mode of transmission, namely (i) human-to-human via aerosols or direct contact; (ii) direct inoculation (e.g. injury); and (iii) transmission to humans from environmental or zoonotic reservoirs, and by insects. The importance of the different transmission pathways and the strength of the evidence were assessed considering the number of publications describing similar findings, the consistency of the findings and the methodological quality of the studies. A total of 79 relevant articles were retained out of 3,805 hits resulting from the application of the search strategy. Solid evidence for transmission among contacts exists, and for zoonotic leprosy in the southern States of the USA. Based on the extant evidence, skin-to-skin contact, aerosols/droplets and shedding of bacteria into the environment and subsequent infection, e.g. through dust or small wounds, all remain possible options. No study has unequivocally demonstrated the mechanisms by which M. leprae bacteria travel from one case of leprosy to another.
Do we need a new definition of the overactive bladder syndrome? ICI-RS 2013.
Drake, Marcus J
2014-06-01
Overactive bladder syndrome (OAB) has a symptom-based definition. Following a presentation of issues, the definition was subjected to expert discussion at the International Consultation on Incontinence Research Society to identify key issues. OAB is a widely used term; it is a pragmatic approach to categorizing a recognized group of patients, and is understood by the patients, however, expert opinion suggested several issues for which additional evidence should be sought. Naming an organ (bladder) in the condition may suggest underlying mechanism, when contributory aspects may lie outside the bladder. No severity thresholds are set, which can cause uncertainty. Urgency is prominent in the definition, but may not be prominent in patients whose adaptive behavior reduces their propensity to urgency. OAB can co-exist with other common conditions, such as benign prostate enlargement (BPE), stress incontinence or nocturnal polyuria. Consensus led by the International Continence Society can be attempted for aspects such as "fear of leakage." To develop a new definition, more substantive evidence is needed for key elements, and until such evidence is available, full redefinition is not appropriate. Thus, the medical profession should accept constructive compromise and work supportively. The ICI-RS proposes that the terminology is slightly rephrased as: "overactive bladder syndrome (OAB) is characterized by urinary urgency, with or without urgency urinary incontinence, usually with increased daytime frequency and nocturia, if there is no proven infection or other obvious pathology." More substantive changes would require additional scientific evidence. Strengths, limitations, and practicalities of the definition of OAB were discussed at the ICIRS meeting 2013. Following a presentation of issues, the definition was subjected to expert discussion. © 2014 Wiley Periodicals, Inc.
2017-01-01
Normal aging is associated with a decline in episodic memory and also with aggregation of the β-amyloid (Aβ) and tau proteins and atrophy of medial temporal lobe (MTL) structures crucial to memory formation. Although some evidence suggests that Aβ is associated with aberrant neural activity, the relationships among these two aggregated proteins, neural function, and brain structure are poorly understood. Using in vivo human Aβ and tau imaging, we demonstrate that increased Aβ and tau are both associated with aberrant fMRI activity in the MTL during memory encoding in cognitively normal older adults. This pathological neural activity was in turn associated with worse memory performance and atrophy within the MTL. A mediation analysis revealed that the relationship with regional atrophy was explained by MTL tau. These findings broaden the concept of cognitive aging to include evidence of Alzheimer's disease-related protein aggregation as an underlying mechanism of age-related memory impairment. SIGNIFICANCE STATEMENT Alterations in episodic memory and the accumulation of Alzheimer's pathology are common in cognitively normal older adults. However, evidence of pathological effects on episodic memory has largely been limited to β-amyloid (Aβ). Because Aβ and tau often cooccur in older adults, previous research offers an incomplete understanding of the relationship between pathology and episodic memory. With the recent development of in vivo tau PET radiotracers, we show that Aβ and tau are associated with different aspects of memory encoding, leading to aberrant neural activity that is behaviorally detrimental. In addition, our results provide evidence linking Aβ- and tau-associated neural dysfunction to brain atrophy. PMID:28213439
Culture and end of life care: a scoping exercise in seven European countries.
Gysels, Marjolein; Evans, Natalie; Meñaca, Arantza; Andrew, Erin; Toscani, Franco; Finetti, Sylvia; Pasman, H Roeline; Higginson, Irene; Harding, Richard; Pool, Robert
2012-01-01
Culture is becoming increasingly important in relation to end of life (EoL) care in a context of globalization, migration and European integration. We explore and compare socio-cultural issues that shape EoL care in seven European countries and critically appraise the existing research evidence on cultural issues in EoL care generated in the different countries. We scoped the literature for Germany, Norway, Belgium, The Netherlands, Spain, Italy and Portugal, carrying out electronic searches in 16 international and country-specific databases and handsearches in 17 journals, bibliographies of relevant papers and webpages. We analysed the literature which was unearthed, in its entirety and by type (reviews, original studies, opinion pieces) and conducted quantitative analyses for each country and across countries. Qualitative techniques generated themes and sub-themes. A total of 868 papers were reviewed. The following themes facilitated cross-country comparison: setting, caregivers, communication, medical EoL decisions, minority ethnic groups, and knowledge, attitudes and values of death and care. The frequencies of themes varied considerably between countries. Sub-themes reflected issues characteristic for specific countries (e.g. culture-specific disclosure in the southern European countries). The work from the seven European countries concentrates on cultural traditions and identities, and there was almost no evidence on ethnic minorities. This scoping review is the first comparative exploration of the cultural differences in the understanding of EoL care in these countries. The diverse body of evidence that was identified on socio-cultural issues in EoL care, reflects clearly distinguishable national cultures of EoL care, with differences in meaning, priorities, and expertise in each country. The diverse ways that EoL care is understood and practised forms a necessary part of what constitutes best evidence for the improvement of EoL care in the future.
What Can Plasticity Contribute to Insect Responses to Climate Change?
Sgrò, Carla M; Terblanche, John S; Hoffmann, Ary A
2016-01-01
Plastic responses figure prominently in discussions on insect adaptation to climate change. Here we review the different types of plastic responses and whether they contribute much to adaptation. Under climate change, plastic responses involving diapause are often critical for population persistence, but key diapause responses under dry and hot conditions remain poorly understood. Climate variability can impose large fitness costs on insects showing diapause and other life cycle responses, threatening population persistence. In response to stressful climatic conditions, insects also undergo ontogenetic changes including hardening and acclimation. Environmental conditions experienced across developmental stages or by prior generations can influence hardening and acclimation, although evidence for the latter remains weak. Costs and constraints influence patterns of plasticity across insect clades, but they are poorly understood within field contexts. Plastic responses and their evolution should be considered when predicting vulnerability to climate change-but meaningful empirical data lag behind theory.
The meaning of women's experiences of living with multiple sclerosis.
Olsson, Malin; Lexell, Jan; Söderberg, Siv
2008-04-01
We conducted a qualitative inquiry in order to describe the meaning of women's experiences of living with multiple sclerosis (MS). Multiple sclerosis is a chronic autoimmune disease of the central nervous system. The majority of persons living with MS are women. Living with MS has been described as difficult because of the uncertainty of the illness. Ten women with MS were interviewed and the interviews were analyzed with a phenomenological hermeneutic interpretation. In this study, we suggest that the meaning of living with MS for women can be understood as trying to maintain power and living with an unrecognizable body. The bodies of women with MS serve as hindrances in everyday life. Bodily changes evident to others impose feelings of being met in a different way, which can be understood as an expression of a violated dignity. At the same time, the women with MS struggle to protect their dignity.
[Forensic entomology exemplified by a homicide. A combined stain and postmortem time analysis].
Benecke, M; Seifert, B
1999-01-01
The combined analysis of both ant and blow fly evidence recovered from a corpse, and from the boot of a suspect, suggested that an assumed scenario in a high profile murder case was likely to be true. The ants (Lasius fuliginous) were used as classical crime scene stains that linked the suspect to the scene. Blow fly maggots (Calliphora spec.) helped to determine the post mortem interval (PMI) with the calculated PMI overlapping with the assumed time of the killing. In the trial, the results of the medico-legal analysis of the insects was understood to be crucial scientific evidence, and the suspect was sentenced to 8 years in prison.
Amino Acid Sensing in Skeletal Muscle
Moro, Tatiana; Ebert, Scott M.; Adams, Christopher M.; Rasmussen, Blake B.
2016-01-01
Aging impairs skeletal muscle protein synthesis, leading to muscle weakness and atrophy. However, the underlying molecular mechanisms remain poorly understood. Here, we review evidence that mTORC1- and ATF4-mediated amino acid sensing pathways, triggered by impaired amino acid delivery to aged skeletal muscle, may play important roles in skeletal muscle aging. Interventions that alleviate age-related impairments in muscle protein synthesis, strength and/or muscle mass appear to do so by reversing age-related changes in skeletal muscle amino acid delivery, mTORC1 activity and/or ATF4 activity. An improved understanding of the mechanisms and roles of amino acid sensing pathways in skeletal muscle may lead to evidence-based strategies to attenuate sarcopenia. PMID:27444066
The volatility of stock market prices.
Shiller, R J
1987-01-02
If the volatility of stock market prices is to be understood in terms of the efficient markets hypothesis, then there should be evidence that true investment value changes through time sufficiently to justify the price changes. Three indicators of change in true investment value of the aggregate stock market in the United States from 1871 to 1986 are considered: changes in dividends, in real interest rates, and in a direct measure of intertemporal marginal rates of substitution. Although there are some ambiguities in interpreting the evidence, dividend changes appear to contribute very little toward justifying the observed historical volatility of stock prices. The other indicators contribute some, but still most of the volatility of stock market prices appears unexplained.
Ho, Joon Wee
2012-03-01
Bisphosphonates are used in the oncological setting to treat and prevent skeletal-related events and preserve bone mineral density. Bisphosphonates also possess a hypocalcaemic effect. When undesired, hypocalcaemia can result in increased morbidity and complications. The currently understood mechanism of bisphosphonate-induced hypocalcaemia is by osteoclast inhibition. The effect of bisphosphonates on osteoblasts is less well understood. Laboratory studies demonstrate that bisphosphonates increase osteoblast and osteoblastic metastases maturation, activity and bone mineralization. We hypothesize that where large populations of osteoblasts exist increased mineralization may result in hypocalcaemia. Consequently patients with bone-metastatic prostate cancer may be more susceptible to symptomatic hypocalcaemia following bisphosphonate therapy. We are currently designing a study to investigate our hypothesis and to identify the risk factors of hypocalcaemia. Copyright © 2011 Elsevier Ltd. All rights reserved.
Constraint-Induced Movement Therapy after Stroke
Kwakkel, Gert; Veerbeek, Janne M.; van Wegen, Erwin E.H.; Wolf, Steven L.
2015-01-01
Constraint-induced movement therapy (CIMT) was developed to overcome upper limb impairments after stroke and is the most investigated intervention for treating stroke patients in the previous decades. This review describes the current evidence regarding: original CIMT and modified versions of CIMT (mCIMT). Meta-analysis showed strong evidence favoring both types of CIMT in terms of motor function, arm-hand activities and self-reported arm-hand functioning in daily life, immediately after treatment and at long-term follow-up, whereas no evidence was found for constraining alone (Forced Use (FU) therapy). No evidence was found that type of CIMT, intensity of practice or timing did affect outcome. Although the underlying mechanism that drive (m)CIMT is still poorly understood, recent kinematic conducted studies suggests that improvements introduced by original CIMT or mCIMT are mainly based on adaptation by learning to optimize the use of intact end-effectors by selecting patients with some voluntary motor control of wrist and finger extensors post stroke. PMID:25772900
Parry, Charles D H; Myers, Bronwyn J
2014-03-12
Inkatha Freedom Party MP Mario Oriani-Ambrosini's impassioned plea to legalise the medical use of cannabis must be understood in the context of his own condition as well as legislative changes in at least ten countries. This article argues that any decisions to shift policy must be based on a consideration of the evidence on the risks and benefits associated with the medical use of cannabis for the individual and broader society. It concludes that there are important gaps in the evidence base, particularly in human trials supporting the efficacy of cannabis use for treating and preventing medical conditions and alleviating negative symptoms associated with these conditions. South African researchers should be enabled actively to support development of the necessary evidence base actively by conducting preclinical and clinical research in this area. Human trials to establish the efficacy of the use of cannabis/cannabinoids in addressing AIDS wasting syndrome and other negative sequelae of HIV and AIDS are especially needed.
Routray, Samapika; Mohanty, Neeta
2014-01-01
Cancer stem cells (CSCs) play a major role in local recurrence and metastatic spread in head and neck squamous cell carcinomas (HNSCC). Evidence suggests that cancer stem cells are resistant to conventional therapy. So the emerging concepts of the role of cancer stem cells in the pathobiology of HNSCC should be understood carefully to be able to create new paradigms in treatment plans.
Routray, Samapika; Mohanty, Neeta
2014-01-01
Cancer stem cells (CSCs) play a major role in local recurrence and metastatic spread in head and neck squamous cell carcinomas (HNSCC). Evidence suggests that cancer stem cells are resistant to conventional therapy. So the emerging concepts of the role of cancer stem cells in the pathobiology of HNSCC should be understood carefully to be able to create new paradigms in treatment plans. PMID:24693428
Potential role of orexin and sleep modulation in the pathogenesis of Alzheimer's disease.
Roh, Jee Hoon; Jiang, Hong; Finn, Mary Beth; Stewart, Floy R; Mahan, Thomas E; Cirrito, John R; Heda, Ashish; Snider, B Joy; Li, Mingjie; Yanagisawa, Masashi; de Lecea, Luis; Holtzman, David M
2014-12-15
Age-related aggregation of amyloid-β (Aβ) is an upstream pathological event in Alzheimer's disease (AD) pathogenesis, and it disrupts the sleep-wake cycle. The amount of sleep declines with aging and to a greater extent in AD. Poor sleep quality and insufficient amounts of sleep have been noted in humans with preclinical evidence of AD. However, how the amount and quality of sleep affects Aβ aggregation is not yet well understood. Orexins (hypocretins) initiate and maintain wakefulness, and loss of orexin-producing neurons causes narcolepsy. We tried to determine whether orexin release or secondary changes in sleep via orexin modulation affect Aβ pathology. Amyloid precursor protein (APP)/Presenilin 1 (PS1) transgenic mice, in which the orexin gene is knocked out, showed a marked decrease in the amount of Aβ pathology in the brain with an increase in sleep time. Focal overexpression of orexin in the hippocampus in APP/PS1 mice did not alter the total amount of sleep/wakefulness and the amount of Aβ pathology. In contrast, sleep deprivation or increasing wakefulness by rescue of orexinergic neurons in APP/PS1 mice lacking orexin increased the amount of Aβ pathology in the brain. Collectively, modulation of orexin and its effects on sleep appear to modulate Aβ pathology in the brain. © 2014 Roh et al.
NASA Astrophysics Data System (ADS)
Zhang, Qiujia; You, Jiang; Volkow, Nora D.; Choi, Jeonghun; Yin, Wei; Wang, Wei; Pan, Yingtian; Du, Congwu
2016-02-01
Cocaine abuse can lead to cerebral strokes and hemorrhages secondary to cocaine's cerebrovascular effects, which are poorly understood. We assessed cocaine's effects on cerebrovascular anatomy and function in the somatosensory cortex of the rat's brain. Optical coherence tomography was used for in vivo imaging of three-dimensional cerebral blood flow (CBF) networks and to quantify CBF velocities (CBFv), and multiwavelength laser-speckle-imaging was used to simultaneously measure changes in CBFv, oxygenated (Δ[HbO2]) and deoxygenated hemoglobin (Δ[HbR]) concentrations prior to and after an acute cocaine challenge in chronically cocaine exposed rats. Immunofluorescence techniques on brain slices were used to quantify microvasculature density and levels of vascular endothelial growth factor (VEGF). After chronic cocaine (2 and 4 weeks), CBFv in small vessels decreased, whereas vasculature density and VEGF levels increased. Acute cocaine further reduced CBFv and decreased Δ[HbO2] and this decline was larger and longer lasting in 4 weeks than 2 weeks cocaine-exposed rats, which indicates that risk for ischemia is heightened during intoxication and that it increases with chronic exposures. These results provide evidence of cocaine-induced angiogenesis in cortex. The CBF reduction after chronic cocaine exposure, despite the increases in vessel density, indicate that angiogenesis was insufficient to compensate for cocaine-induced disruption of cerebrovascular function.