Dementia and osteoporosis in a geriatric population: Is there a common link?

AIM To determine the existence of a common pathological link between dementia and osteoporosis through reviewing the current evidence base. METHODS This paper reviews the current literature on osteoporosis and dementia in order to ascertain evidence of a common predisposing aetiology. A literature search of Ovid MEDLINE (1950 to June 2016) was conducted. The keywords “osteoporosis”, “osteoporotic fracture”, “dementia” and “Alzheimer’s disease” (AD) were used to determine the theoretical links with the most significant evidence base behind them. The key links were found to be vitamins D and K, calcium, thyroid disease, statins, alcohol and sex steroids. These subjects were then searched in combination with the previous terms and the resulting papers manually examined. Theoretical, in vitro and in vivo research were all used to inform this review which focuses on the most well developed theoretical common causes for dementia (predominantly Alzheimer’s type) and osteoporosis. RESULTS Dementia and osteoporosis are multifaceted disease processes with similar epidemiology and a marked increase in prevalence in elderly populations. The existence of a common link between the two has been suggested despite a lack of clear pathological overlap in our current understanding. Research to date has tended to be fragmented and relatively weak in nature with multiple confounding factors reflecting the difficulties of in vivo experimentation in the population of interest. Despite exploration of various possible mechanisms in search for a link between the two pathologies, this paper found that it is possible that these associations are coincidental due to the nature of the evidence available. One finding in this review is that prior investigation into common aetiologies has found raised amyloid beta peptide levels in osteoporotic bone tissue, with a hypothesis that amyloid beta disorders are systemic disorders resulting in differing tissue manifestations. However, our findings were that the most compelling evidence of a common yet independent aetiology lies in the APOE4 allele, which is a well-established risk for AD but also carries an independent association with fracture risk. The mechanism behind this is thought to be the reduced plasma vitamin K levels in individuals exhibiting the APOE4 allele which may be amplified by the nutritional deficiencies associated with dementia, which are known to include vitamins K and D. The vitamin theory postulates that malnutrition and reduced exposure to sunlight in patients with AD leads to vitamin deficiencies. CONCLUSION Robust evidence remains to be produced regarding potential links and regarding the exact aetiology of these diseases and remains relevant given the burden of dementia and osteoporosis in our ageing population. Future research into amyloid beta, APOE4 and vitamins K and D as the most promising aetiological links should be welcomed

Alcohol-induced retrograde facilitation renders witnesses of crime less suggestible to misinformation

RATIONALE: Research has shown that alcohol can have both detrimental and facilitating effects on memory: intoxication can lead to poor memory for information encoded after alcohol consumption (anterograde amnesia) and may improve memory for information encoded before consumption (retrograde facilitation). This study examined whether alcohol consumed after witnessing a crime can render individuals less vulnerable to misleading post-event information (misinformation). METHOD: Participants watched a simulated crime video. Thereafter, one third of participants expected and received alcohol (alcohol group), one third did not expect but received alcohol (reverse placebo), and one third did not expect nor receive alcohol (control). After alcohol consumption, participants were exposed to misinformation embedded in a written narrative about the crime. The following day, participants completed a cued-recall questionnaire about the event. RESULTS: Control participants were more likely to report misinformation compared to the alcohol and reverse placebo group. CONCLUSION: The findings suggest that we may oversimplify the effect alcohol has on suggestibility and that sometimes alcohol can have beneficial effects on eyewitness memory by protecting against misleading post-event information

MFGE8 does not influence chorio-retinal homeostasis or choroidal neovascularization in vivo

Purpose: Milk fat globule-epidermal growth factor-factor VIII (MFGE8) is necessary for diurnal outer segment phagocytosis and promotes VEGF-dependent neovascularization. The prevalence of two single nucleotide polymorphisms (SNP) in MFGE8 was studied in two exsudative or “wet” Age-related Macular Degeneration (AMD) groups and two corresponding control groups. We studied the effect of MFGE8 deficiency on retinal homeostasis with age and on choroidal neovascularization (CNV) in mice. Methods: The distribution of the SNP (rs4945 and rs1878326) of MFGE8 was analyzed in two groups of patients with “wet” AMD and their age-matched controls from Germany and France. MFGE8-expressing cells were identified in Mfge8+/− mice expressing ß-galactosidase. Aged Mfge8+/− and Mfge8−/− mice were studied by funduscopy, histology, electron microscopy, scanning electron microscopy of vascular corrosion casts of the choroid, and after laser-induced CNV. Results: rs1878326 was associated with AMD in the French and German group. The Mfge8 promoter is highly active in photoreceptors but not in retinal pigment epithelium cells. Mfge8−/− mice did not differ from controls in terms of fundus appearance, photoreceptor cell layers, choroidal architecture or laser-induced CNV. In contrast, the Bruch's membrane (BM) was slightly but significantly thicker in Mfge8−/− mice as compared to controls. Conclusions: Despite a reproducible minor increase of rs1878326 in AMD patients and a very modest increase in BM in Mfge8−/− mice, our data suggests that MFGE8 dysfunction does not play a critical role in the pathogenesis of AMD

The Chronus Quantum software package

The Chronus Quantum (ChronusQ) software package is an open source (under the GNU General Public License v2) software infrastructure which targets the solution of challenging problems that arise in ab initio electronic structure theory. Special emphasis is placed on the consistent treatment of time dependence and spin in the electronic wave function, as well as the inclusion of relativistic effects in said treatments. In addition, ChronusQ provides support for the inclusion of uniform finite magnetic fields as external perturbations through the use of gauge-including atomic orbitals. ChronusQ is a parallel electronic structure code written in modern C++ which utilizes both message passing implementation and shared memory (OpenMP) parallelism. In addition to the examination of the current state of code base itself, a discussion regarding ongoing developments and developer contributions will also be provided. This article is categorized under: Software > Quantum Chemistry Electronic Structure Theory > Ab Initio Electronic Structure Methods Electronic Structure Theory > Density Functional Theory

Radio pulsar populations

The goal of this article is to summarize the current state of play in the field of radio pulsar statistics. Simply put, from the observed sample of objects from a variety of surveys with different telescopes, we wish to infer the properties of the underlying sample and to connect these with other astrophysical populations (for example supernova remnants or X-ray binaries). The main problem we need to tackle is the fact that, like many areas of science, the observed populations are often heavily biased by a variety of selection effects. After a review of the main effects relevant to radio pulsars, I discuss techniques to correct for them and summarize some of the most recent results. Perhaps the main point I would like to make in this article is that current models to describe the population are far from complete and often suffer from strong covariances between input parameters. That said, there are a number of very interesting conclusions that can be made concerning the evolution of neutron stars based on current data. While the focus of this review will be on the population of isolated Galactic pulsars, I will also briefly comment on millisecond and binary pulsars as well as the pulsar content of globular clusters and the Magellanic Clouds.Comment: 16 pages, 6 figures, to appear in Proceedings of ICREA Workshop on The High-Energy Emission from Pulsars and their Systems, Sant Cugat, Spain, 2010 April 12-16 (Springer

Disentangling Fun and Enjoyment in Exergames Using an Expanded Design, Play, Experience Framework: A Narrative Review

published_or_final_versio

Associations of sitting accumulation patterns with cardio-metabolic risk biomarkers in Australian adults

Backgroun

A systematic variation of the stellar initial mass function in early-type galaxies

Much of our knowledge of galaxies comes from analysing the radiation emitted by their stars. It depends on the stellar initial mass function (IMF) describing the distribution of stellar masses when the population formed. Consequently knowledge of the IMF is critical to virtually every aspect of galaxy evolution. More than half a century after the first IMF determination, no consensus has emerged on whether it is universal in different galaxies. Previous studies indicated that the IMF and the dark matter fraction in galaxy centres cannot be both universal, but they could not break the degeneracy between the two effects. Only recently indications were found that massive elliptical galaxies may not have the same IMF as our Milky Way. Here we report unambiguous evidence for a strong systematic variation of the IMF in early-type galaxies as a function of their stellar mass-to-light ratio, producing differences up to a factor of three in mass. This was inferred from detailed dynamical models of the two-dimensional stellar kinematics for the large Atlas3D representative sample of nearby early-type galaxies spanning two orders of magnitude in stellar mass. Our finding indicates that the IMF depends intimately on a galaxy's formation history.Comment: 4 pages, 2 figures, LaTeX. Accepted for publication as a Nature Letter. More information about our Atlas3D project is available at http://purl.org/atlas3