604 research outputs found
In Arabidopsis thaliana codon volatility scores reflect GC3 composition rather than selective pressure
Background: Synonymous codon usage bias has typically been correlated with, and attributed to translational efficiency. However, there are other pressures on genomic sequence composition that can affect codon usage patterns such as mutational biases. This study provides an analysis of the codon usage patterns in Arabidopsis thaliana in relation to gene expression levels, codon volatility, mutational biases and selective pressures. Results: We have performed synonymous codon usage and codon volatility analyses for all genes in the A. thaliana genome. In contrast to reports for species from other kingdoms, we find that neither codon usage nor volatility are correlated with selection pressure (as measured by dN/dS), nor with gene expression levels on a genome wide level. Our results show that codon volatility and usage are not synonymous, rather that they are correlated with the abundance of G and C at the third codon position (GC3). Conclusions: Our results indicate that while the A. thaliana genome shows evidence for synonymous codon usage bias, this is not related to the expression levels of its constituent genes. Neither codon volatility nor codon usage are correlated with expression levels or selective pressures but, because they are directly related to the composition of G and C at the third codon position, they are the result of mutational bias. Therefore, in A. thaliana codon volatility and usage do not result from selection for translation efficiency or protein functional shift as measured by positive selection
Molecular adaptation of telomere associated genes in mammals
Background: Placental mammals display a huge range of life history traits, including size, longevity, metabolic rate and germ line generation time. Although a number of general trends have been proposed between these traits, there are exceptions that warrant further investigation. Species such as naked mole rat, human and certain bat species all exhibit extreme longevity with respect to body size. It has long been established that telomeres and telomere maintenance have a clear role in ageing but it has not yet been established whether there is evidence for adaptation in telomere maintenance proteins that could account for increased longevity in these species. Results: Here we carry out a molecular investigation of selective pressure variation, specifically focusing on telomere associated genes across placental mammals. In general we observe a large number of instances of positive selection acting on telomere genes. Although these signatures of selection overall are not significantly correlated with either longevity or body size we do identify positive selection in the microbat species Myotis lucifugus in functionally important regions of the telomere maintenance genes DKC1 and TERT, and in naked mole rat in the DNA repair gene BRCA1. Conclusion: These results demonstrate the multifarious selective pressures acting across the mammal phylogeny driving lineage-specific adaptations of telomere associated genes. Our results show that regardless of the longevity of a species, these proteins have evolved under positive selection thereby removing increased longevity as the single selective force driving this rapid rate of evolution. However, evidence of molecular adaptations specific to naked mole rat and Myotis lucifugus highlight functionally significant regions in genes that may alter the way in which telomeres are regulated and maintained in these longer-lived species
Designing hollow nano gold golf balls.
Hollow/porous nanoparticles, including nanocarriers, nanoshells, and mesoporous materials have applications in catalysis, photonics, biosensing, and delivery of theranostic agents. Using a hierarchical template synthesis scheme, we have synthesized a nanocarrier mimicking a golf ball, consisting of (i) solid silica core with a pitted gold surface and (ii) a hollow/porous gold shell without silica. The template consisted of 100 nm polystyrene beads attached to a larger silica core. Selective gold plating of the core followed by removal of the polystyrene beads produced a golf ball-like nanostructure with 100 nm pits. Dissolution of the silica core produced a hollow/porous golf ball-like nanostructure
Hope, quality of life, and benefit from treatment in women having chemotherapy for platinum-resistant/refractory recurrent ovarian cancer
Pre-operative Radiotherapy And Deep Inferior Epigastric Artery Perforator (DIEP) flAp study (PRADA): Aesthetic outcome and patient satisfaction at one year.
INTRODUCTION: The optimal combination of radiotherapy and breast reconstruction has not yet been defined. Post-mastectomy radiotherapy (PMRT) has deleterious effects on breast reconstruction, leading to caution amongst surgeons. Pre-operative radiotherapy (PRT) is a growing area of interest, is demonstrated to be safe, and spares autologous flaps from radiotherapy. This study evaluates the aesthetic outcome of PRT and deep inferior epigastric artery perforator (DIEP) flap reconstruction within the Pre-operative Radiotherapy And Deep Inferior Epigastric artery Perforator (DIEP) flAp (PRADA) cohort. METHODS: PRADA was an observational cohort study designed to evaluate the feasibility and safety of PRT for women undergoing neoadjuvant chemotherapy and DIEP reconstruction. Panel evaluation of 3D surface images (3D-SIs) and patient-reported outcome measures (BREAST-Q) for a subset of women in the study were compared with those of a DIEP-PMRT cohort who had undergone DIEP reconstruction and PMRT. RESULTS: Seventeen out of 33 women from the PRADA study participated in this planned substudy. Twenty-eight women formed the DIEP-PMRT cohort (median follow-up 23 months). The median (inter-quartile range [IQR]) 'satisfaction with breasts' score at 12 months for the PRADA cohort was significantly better than the DIEP-PMRT cohort (77 [72-87] versus 64 [54-71], respectively), p=0.01). Median [IQR] panel evaluation (5-point scale) was also significantly better for the PRADA cohort than for the DIEP-PMRT cohort (4.3 [3.9-4.6] versus 3.6 [2.8-4] p=0.003). CONCLUSIONS: Aesthetic outcome for the PRADA cohort was reported to be 'good' or 'excellent' in 93% of cases using a bespoke panel assessment with robust methodology. Patient satisfaction at one year is encouraging and superior to DIEP-PMRT at 23 months. Switching surgery-radiotherapy sequencing leads to similar breast aesthetic outcomes and warrants further large-scale, multi-centre evaluation in a randomised trial
Health-services utilisation amongst older persons during the last year of life: A population-based study
© 2018 The Author(s). Background: Accurate population-based data regarding hospital-based care utilisation by older persons during their last year of life are important in health services planning. We investigated patterns of acute hospital-based service use at the end of life, amongst older decedents in New South Wales (NSW), Australia. Methods: Data from all persons aged ≥70 years who died in the state of NSW Australia in 2007 were included. Several measures of hospital-based service utilisation during the last year of life were assessed from retrospectively linked data comprising data for all registered deaths, cause of death, hospital care during the last year of life (NSW Admitted Patient Data Collection [APDC] and Emergency Department [ED] Data Collection [EDDC]), and the NSW Cancer Registry. Results: Amongst 34,556 decedents aged ≥70 years, 82% (n = 28,366) had ≥1 hospitalisation during the last year of life (median 2), and 21% > 3 hospitalisations. Twenty-five percent (n = 5485) of decedents attended ED during the last week of life. Overall, 21% had a hospitalisation > 30 days in the last year of life, and 7% spent > 3 months in hospital; 79% had ≥1 ED attendance, 17% > 3. Nine percent (n = 3239) spent time in an intensive care unit. Fifty-three percent (n = 18,437) died in an inpatient setting. Hospital records had referenced palliative care for a fifth (7169) of decedents. Adjusting for age group, sex, place of residence, area-level socioeconomic status, and cause of death, having > 3 hospitalisations during the last year of life was more likely for persons dying from cancer (35% versus 16% non-cancer deaths, adjusted odds ratio [aOR] 2.33), 'younger' old decedents (29% for age 70-79 and 20% for age 80-89 versus 11% for 90+, aOR 2.42 and 1.77 respectively) and males (25% versus 17% females, aOR 1.38). Patterns observed for other hospital-based service use were similar. Conclusions: This population-based study reveals high use of hospital care among older persons during their last year of life, although this decreased with increasing older age, providing important data to inform health services planning for this population, and highlighting aspects requiring further study
Fas ligand mediates immune privilege and not inflammation in human colon cancer, irrespective of TGF-β expression
Initial experience of the BREAST-Q breast-conserving therapy module.
Purpose The most recently developed module of the BREAST-Q, a validated patient outcome measure, is for patients who have undergone breast-conserving therapy (BCT) for cancer. This aim of this study was to assess patient satisfaction and quality of life after BCT using BREAST-Q, investigate clinical risk factors for lower satisfaction and explore the relationship between patient satisfaction with the appearance of their breasts and the other domains of the BREAST-Q.Methods Women who had undergone unilateral BCT in the preceding 1-6 years were invited to participate at the time of their annual surveillance mammogram. Clinicopathological data were collected from an electronic database. Linear regression was used to evaluate risk factors for lower satisfaction. Spearman's rho correlation coefficients were calculated to evaluate the relationship between domains.Results 200 women completed the questionnaire. Mean age was 60 years (SD 11.1). Time from surgery was 35.5 months (SD 17.8). Median score for 'Satisfaction with breasts' was 68 (interquartile range 55-80). Lowest scores were for 'sexual wellbeing' (57, IQR 45-66). On multivariate analysis, BMI at the time of surgery (p = 0.002), delayed wound healing (p = 0.001) and axillary surgery (p = 0.003) were independent risk factors for lower satisfaction. There was significant correlation between 'Satisfaction with breasts' and all other BREAST-Q domains.Conclusion High BMI, delayed wound healing and axillary surgery are risk factors for lower patient satisfaction. This first publication reporting the whole dataset for the BREAST-Q BCT will serve as a benchmark for future studies of patient satisfaction following BCT
Expression of transforming growth factor-β (TGF-β) in chronic idiopathic cough
In patients with chronic idiopathic cough, there is a chronic inflammatory response together with evidence of airway wall remodelling and an increase in airway epithelial nerves expressing TRPV-1. We hypothesised that these changes could result from an increase in growth factors such as TGFβ and neurotrophins
The potential role of three-dimensional surface imaging as a tool to evaluate aesthetic outcome after Breast Conserving Therapy (BCT).
Purpose To establish whether objective measurements of symmetry of volume and shape using three-dimensional surface imaging (3D-SI) can be used as surrogate markers of aesthetic outcome in patients who have undergone breast conserving therapy (BCT).Methods Women who had undergone unilateral BCT in the preceding 1-6 years were invited to participate. Participants completed a satisfaction questionnaire (BREAST-Q) and underwent 3D-SI. Volume and surface symmetry were measured on the images. Assessment of aesthetic outcome was undertaken by a panel of clinicians. The Kruskal-Wallis test was used to assess the relationship between volume and shape symmetry measurements with the panel score. Spearman's rho correlations were used to assess the relationship between the measurements and patient satisfaction.Results 200 women participated. Median volume symmetry was 87% (IQR 78-93) and shape symmetry was 5.9 mm (IQR 4.2-8.0). The participants were grouped according to panel assessment of aesthetic outcome (poor, fair, good, excellent) and the median volume and shape symmetry was calculated for each group. Volume symmetry significantly differed between the groups. Post hoc pairwise comparisons demonstrated that these differences existed between panel scores of fair versus good and good versus excellent. Median shape symmetry also differed according to patient panel groups with four significant pairwise comparisons between poor versus good, poor versus excellent, fair versus good and fair versus excellent. There was a significant but weak correlation of both volume symmetry and surface asymmetry with BREAST-Q scores (correlation coefficients 0.187 and -0.229, respectively).Conclusion Breast volume and shape symmetry are both associated with panel assessment scores and patient satisfaction. The objective volume and shape symmetry measures were strongly associated with panel assessment scores, such that a 3D-SI tool could replace panel assessment as a faster and more objective method of evaluating aesthetic outcomes
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