797 research outputs found
Gene Expression Profiling of Peripheral Tissues in Amyotrophic Lateral Sclerosis
Background: Amyotrophic Lateral Sclerosis, in which cortical and spinal motor neurons degenerate, is a late onset neurodegenerative condition that accounts for ~1 in 400 UK deaths, typically within 3-5 years from the initial manifestations of disease. It forms part of a broad spectrum of clinically, genetically as well as pathologically heterogeneous disorders that include behavioural variant frontotemporal lobar degeneration (bvFTLD). A large intronic hexanucleotide G4C2 repeat expansion of >30 copies was recently identified, in 2011, in the previously uncharacterised chromosome 9 open reading frame 72 (C9ORF72) gene which is now thought to explain up to 43% of familial ALS (~20-30% of familial FTLD) and around 7% of sporadic cases. Rationale & Hypothesis: The principle aim of the PhD was to perform gene expression profiling of peripheral tissues in ALS. In the first instance whole blood was trialled. However, this proved unreliable, owing to the shear abundance of erythrocyte derived alpha and beta haemoglobin transcripts that are contained within the sample and the variability in the efficiency of its removal using the Ambion® GLOBINClear or NuGEN Ovation® WB reduction strategies. Instead disease related changes in transcription/alternative splicing were detected in a large bank (n=820) of patient and control lymphoblastoid cell lines (LCL’s) with the main purpose of: 1) elucidating further the mechanism(s) of neurotoxicity associated with the C9ORF72 G4C2 repeat expansion and, 2) establishing within this specific genetic subtype, modifiers of a fast (<2yrs) versus slow (≥4yrs) disease progression in order to identify potential new areas of therapeutic research. Methodology: Biotinylated, sense-strand cDNA targets of ~40 -70nt were hybridized onto Human Exon 1.0ST GeneChip® Arrays. A GC-RMA normalisation procedure was carried out in Partek® Genomics Suite and differentially expressed or alternatively spliced transcripts were detected at the 5% significance level (p<0.05) with a fold-change threshold of ≥ ±1.20 applied. Findings: Overall a marginal increase in gene transcription was observed with respect to C9ORF72 (59.3%, n=650/1,096) and nonC9ORF72-related_SALS patients (63.9%, n=1,148/1,796) compared to neurologically healthy controls. DAVID enriched gene ontology terms included translation, which was specific to carriers of the G4C2 repeat, in addition to RNA processing, DNA metabolism, RNP complex biogenesis and the cell cycle which reflect more common features of the broader ALS phenotype. A number of key validation targets, including several RNA binding partners of the G4C2 repeat (FUS, RPL22, NUDT2, PURA, EIF4H and HNRNPA0/F) were subsequently confirmed in a qRT-PCR assay. Isoform A/B specific transcripts of the C9ORF72 gene, itself, were found not to be differentially expressed across the LCL’s in the ECACC discovery and replication cohorts. Conclusions: Whether pathogenicity of the G4C2 expanded allele arises as a consequence of haploinsufficiency or through an aberrant gain of function mechanism has yet to be determined; although emerging evidence favours a role of RNA toxicity. In light of this model, an up-regulation in the expression of C9ORF72 binding partners and other, RNA processing & splicing related transcripts fits with the hypothesis that the cells are attempting to compensate for the sequestration of these proteins into toxic RNA foci in the cytoplasm which leads to disruption of their normal physiological function. Small sample sizes meant limited conclusions could be drawn from the analysis of C9ORF72 specific modifiers of survival in ALS. Clinical data points towards a possible effect of gender which is supported in the literature but other factors such as correlations with expansion length would need to be considered in conducting future work
Activity pattern and fat accumulation strategy of the Natterer’s bat (Vespertilionidae, Chiroptera) swarming population indicate the exact time of male mating effort
Studies concerning bat autumn swarming behavior suggest that the main purpose of this phenomenon is mating. However, the process of fat accumulation is crucial for surviving winter, and it seems to be in clear conflict with a need to strive for the opportunity to mate prior to hibernation. Investment in one activity limits the other one creating a trade-off between them. The aim of our study was to describe the activity pattern of each sex-age group (adult males, adult females, subadults) of the Natterer’s bat during swarming period and to investigate the fat accumulation process of adult males in the context of their reproductive strategy. Bats were captured by mist nets at the swarming site fortnightly from the early August until the late November. The age, sex, reproductive status, and body condition index (mass to forearm ratio, BCI) were recorded. The activity peak of both sexes, adults, and subadults was observed in the late September. That time in season, BCI of adult males was the lowest, and there was no correlation between the hour of an adult male capture and its BCI value within one night (rs = 0.23; p = 0.157). Such correlation was observed later in the season (early October: rs = 0.44; p = 0.020; late October: rs = 0.48; p = 0.002). A negative correlation between adult males’ BCI and proportion of adult females was found (r = 0.44; p = 0.000). We conclude that the activity peak of females is likely to be responsible for the effort of the mating behavior of the males, which is reflected by their low condition index. We suggest that the gleaning foraging strategy of Natterer’s bat allows the males to postpone their fat accumulation until just before hibernation
Insights Arising from Gene Expression Profiling in Amyotrophic Lateral Sclerosis
Public health & preventive medicin
Thromboelastometry - diagnostic examination method of clot formation in pigs subjected to experimental procedures of the left atrial appendage
The Newcastle 85+ study: biological, clinical and psychosocial factors associated with healthy ageing: study protocol
<p>Abstract</p> <p>Background</p> <p>The UK, like other developed countries, is experiencing a marked change in the age structure of its population characterised by increasing life expectancy and continuing growth in the older fraction of the population. There is remarkably little up-to-date information about the health of the <it>oldest old </it>(over 85 years), demographically the fastest growing section of the population. There is a need, from both a policy and scientific perspective, to describe in detail the health status of this population and the factors that influence individual health trajectories. For a very large proportion of medical conditions, age is the single largest risk factor. Gaining new knowledge about why aged cells and tissues are more vulnerable to pathology is likely to catalyse radical new insights and opportunities to intervene. The aims of the Newcastle 85+ Study are to expose the spectrum of health within an inception cohort of 800 85 year-olds; to examine health trajectories and outcomes as the cohort ages and their associations with underlying biological, medical and social factors; and to advance understanding of the biological nature of ageing.</p> <p>Methods</p> <p>A cohort of 800 85 year olds from Newcastle and North Tyneside will be recruited at baseline and followed until the last participant has died. Eligible individuals will be <it>all </it>those who turn 85 during the year 2006 (i.e. born in 1921) and who are registered with a Newcastle or North Tyneside general practice. Participants will be visited in their current residence (own home or institution) by a research nurse at baseline, 18 months and 36 months. The assessment protocol entails a detailed multi-dimensional health assessment together with review of general practice medical records. Participants will be flagged with the NHS Central Register to provide details of the date and cause of death.</p> <p>Discussion</p> <p>The Newcastle 85+ Study will address key questions about health and health-maintenance in the 85+ population, with a particular focus on quantitative assessment of factors underlying variability in health, and on the relationships between health, nutrition and biological markers of the fundamental processes of ageing.</p
The Relational Impact of Multiple Sclerosis: An Integrative Review of the Literature Using a Cognitive Analytic Framework
This integrative literature review uses cognitive analytic therapy (CAT) theory to examine the impact of a chronic illness, multiple sclerosis (MS), on relationships and mental health. Electronic searches were conducted in six medical and social science databases. Thirty-eight articles met inclusion criteria, and also satisfied quality criteria. Articles revealed that MS-related demands change care needs and alter relationships. Using a CAT framework, the MS literature was analysed, and five key patterns of relating to oneself and to others were identified. A diagrammatic formulation is proposed that interconnects these patterns with wellbeing and suggests potential “exits” to improve mental health, for example, assisting families to minimise overprotection. Application of CAT analysis to the literature clarifies relational processes that may affect mental health among individuals with MS, which hopefully will inform how services assist in reducing unhelpful patterns and improve coping. Further investigation of the identified patterns is needed
Fc-Optimized Anti-CD25 Depletes Tumor-Infiltrating Regulatory T Cells and Synergizes with PD-1 Blockade to Eradicate Established Tumors
CD25 is expressed at high levels on regulatory T (Treg) cells and was initially proposed as a target for cancer immunotherapy. However, anti-CD25 antibodies have displayed limited activity against established tumors. We demonstrated that CD25 expression is largely restricted to tumor-infiltrating Treg cells in mice and humans. While existing anti-CD25 antibodies were observed to deplete Treg cells in the periphery, upregulation of the inhibitory Fc gamma receptor (FcγR) IIb at the tumor site prevented intra-tumoral Treg cell depletion, which may underlie the lack of anti-tumor activity previously observed in pre-clinical models. Use of an anti-CD25 antibody with enhanced binding to activating FcγRs led to effective depletion of tumor-infiltrating Treg cells, increased effector to Treg cell ratios, and improved control of established tumors. Combination with anti-programmed cell death protein-1 antibodies promoted complete tumor rejection, demonstrating the relevance of CD25 as a therapeutic target and promising substrate for future combination approaches in immune-oncology
Phylogenetic ctDNA analysis depicts early-stage lung cancer evolution.
The early detection of relapse following primary surgery for non-small-cell lung cancer and the characterization of emerging subclones, which seed metastatic sites, might offer new therapeutic approaches for limiting tumour recurrence. The ability to track the evolutionary dynamics of early-stage lung cancer non-invasively in circulating tumour DNA (ctDNA) has not yet been demonstrated. Here we use a tumour-specific phylogenetic approach to profile the ctDNA of the first 100 TRACERx (Tracking Non-Small-Cell Lung Cancer Evolution Through Therapy (Rx)) study participants, including one patient who was also recruited to the PEACE (Posthumous Evaluation of Advanced Cancer Environment) post-mortem study. We identify independent predictors of ctDNA release and analyse the tumour-volume detection limit. Through blinded profiling of postoperative plasma, we observe evidence of adjuvant chemotherapy resistance and identify patients who are very likely to experience recurrence of their lung cancer. Finally, we show that phylogenetic ctDNA profiling tracks the subclonal nature of lung cancer relapse and metastasis, providing a new approach for ctDNA-driven therapeutic studies
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