4,074 research outputs found
Genomics of lithium action and response
Lithium is the most successful mood stabiliser treatment for bipolar disorder. However, unlike conventional drugs that are designed to interact with a specific molecular target, the actions of lithium are distributed across many biological processes and pathways. Treatment response is subject to genetic variation between individuals and similar genetic variation may dictate susceptibility to side-effects. Transcriptomic, genomic and cell model research strategies have all been deployed in the search for the genetic factors and biological systems that mediate the interaction between genetics and the therapeutic actions of lithium. In this review, recent findings from genome-wide studies and patient cell lines will be summarised and discussed from a standpoint that genuine progress is being made to define clinically useful mechanisms of this treatment, to place it in the context of bipolar disorder pathology, and to move towards a time when the prescription of lithium is targeted to those individuals who will derive the greatest benefit
Schizophrenia biomarkers : translating the descriptive into the diagnostic
While schizophrenia and mental health are qualitatively distinct at the level of clinical presentation, the specific molecular signatures that underlie, or associate with, illness are not. Biomarker identification in schizophrenia is intended to offer a number of important benefits to patient well-being including prediction of future illness, diagnostic clarity and a level of disease description that would guide treatment choice. However, the choice of sample and form of analysis used to produce useful biomarkers is still uncertain. In this review, advances from recent studies spanning the technical spectrum are presented together with comment on their comparative strengths and weaknesses. To date, these studies have aided our understanding of the pathological processes associated with illness much more than they have provided robust biomarkers. A number of reasons for this observation are suggested, as are new strategies for the extraction of biomarkers from large '-omics' datasets
Crystal Structure of the ZrO Phase at Zirconium/Zirconium Oxide Interfaces
Zirconium-based alloys are used in water-cooled nuclear reactors for both nuclear fuel cladding and structural components. Under this harsh environment, the main factor limiting the service life of zirconium cladding, and hence fuel burn-up efficiency, is water corrosion. This oxidation process has recently been linked to the presence of a sub-oxide phase with well-defined composition but unknown structure at the metal–oxide interface. In this paper, the combination of first-principles materials modeling and high-resolution electron microscopy is used to identify the structure of this sub-oxide phase, bringing us a step closer to developing strategies to mitigate aqueous oxidation in Zr alloys and prolong the operational lifetime of commercial fuel cladding alloys
An efficient k.p method for calculation of total energy and electronic density of states
An efficient method for calculating the electronic structure in large systems
with a fully converged BZ sampling is presented. The method is based on a
k.p-like approximation developed in the framework of the density functional
perturbation theory. The reliability and efficiency of the method are
demostrated in test calculations on Ar and Si supercells
Post-aragonite phases of CaCO at lower mantle pressures
The stability, structure and properties of carbonate minerals at lower mantle
conditions has significant impact on our understanding of the global carbon
cycle and the composition of the interior of the Earth. In recent years, there
has been significant interest in the behavior of carbonates at lower mantle
conditions, specifically in their carbon hybridization, which has relevance for
the storage of carbon within the deep mantle. Using high-pressure synchrotron
X-ray diffraction in a diamond anvil cell coupled with direct laser heating of
CaCO using a CO laser, we identify a crystalline phase of the
material above 40 GPa corresponding to a lower mantle depth of around 1,000
km which has first been predicted by \textit{ab initio} structure
predictions. The observed carbon hybridized species at 40 GPa is
monoclinic with symmetry and is stable up to 50 GPa, above which it
transforms into a structure which cannot be indexed by existing known phases. A
combination of \textit{ab initio} random structure search (AIRSS) and
quasi-harmonic approximation (QHA) calculations are used to re-explore the
relative phase stabilities of the rich phase diagram of CaCO. Nudged
elastic band (NEB) calculations are used to investigate the reaction mechanisms
between relevant crystal phases of CaCO and we postulate that the mineral
is capable of undergoing - hybridization change purely in the
structure forgoing the accepted post-aragonite structure.Comment: 12 pages, 8 figure
Quantification of global mitochondrial DNA methylation levels and inverse correlation with age at two CpG sites
Mammalian ageing features biological attrition evident at cellular, genetic and epigenetic levels. Mutation of mitochondrial DNA, and nuclear DNA methylation changes are well established correlates of ageing. The methylation of mitochondrial DNA (mtDNA) is a new and incompletely described phenomenon with unknown biological control and significance. Here we describe the bisulphite sequencing of mtDNA from 82 individuals aged 18-91 years. We detected low and variable levels of mtDNA methylation at 54 of 133 CpG sites interrogated. Regression analysis of methylation levels at two CpG sites (M1215 and M1313) located within the 12S ribosomal RNA gene showed an inverse correlation with subject age suggesting their utility as epigenetic markers of ageing
Electron spectroscopy of carbon materials: Experiment and theory
We present a comparative spectroscopic study of carbon as graphite, diamond and C60 using C1s K-edge electron energy-loss spectroscopy (EELS), X-ray emission spectroscopy, and theoretical modelling. The first principles calculations of these spectra are obtained in the local density approximation using a self-consistent Gaussian basis pseudo-potential method. Calculated spectra show excellent agreement with experiment and are able to discriminate not only between various carbon hybridisations but also local variation in environment. Core-hole effects on the calculated spectra are also investigated. For the first time, the EEL spectrum of carbyne is calculated
The EpiTect Methyl qPCR Assay as novel age estimation method in forensic biology
Human aging is associated with epigenetic modification of the genome. DNA methylation at cytosines appears currently as the best characterised modification that occurs during the mammalian lifetime. Such methylation changes at regulatory region can provide insights to track contributor age for criminal investigation. The EpiTect Methyl II PCR system (QIAGEN) was used to compare methylation levels of CpG islands in the promoter regions of a number of age related genes, of which four successfully showed changes across the lifespan (NPTX2, KCNQ1DN, GRIA2 and TRIM58). This technique is based on the detection of remaining input genome after digestion with a methylation-sensitive restriction enzyme. This study examined DNA specimens from 80 female subjects of various ages (18-91 years) obtained from blood, using primers designed to flank the studied gene loci. The data obtained from DNA methylation quantification showed successful discrimination among volunteered ages. Overall, the difference between predicted and real age was about 11 years and absolute mean differences (AMD) was only 7.2 years error. We suggest the EpiTect system can be used as fast and simple innovative tool in future forensic age estimation
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