1,672 research outputs found
The Meckel-Gruber Syndrome protein TMEM67 (meckelin) regulates basal body planar polarization and non-canonical Wnt signalling via Wnt5a and ROR2
Does education explain the terminal decline in the oldest-old? Evidence from two longitudinal studies of ageing
AbstractBackground Cognitive performance substantially deteriorates close to death, as postulated by the terminal decline hypothesis. However, the association between education and terminal decline remains controversial. This study investigated the role of education in terminal decline in two European longitudinal studies of oldest-old. Methods Participants were from the Newcastle 85+, UK (n=702), and Octogenarian Twins (OCTO-Twin), Sweden (n= 845). They were assessed biannually over three and five consecutive waves, respectively. In a coordinated analysis, multilevel models were used to examine the association between education and terminal decline on mini-mental state examination (MMSE), controlling for age at baseline, dementia incidence, sex, and time to death from the study entry within each cohort. Cognitive decline was modelled as a linear function of time to death in both cohorts and as a quadratic function in the OCTO-Twin study (because of longer follow-up). Education was a continuous measure (ranging from 6 to 20 years in Newcastle 85+ and 0 to 23 years in OCTO-Twin). Findings A typical British man, aged 85 at baseline, with 10 years’ education, entered the terminal phase at around 2·5 years before death, and the mean rate of decline was −1·04 MMSE points with each year closer to the time of death (SEM 0·25, p<0·0001). By contrast, a Swedish man, aged 83 years, with an average of 7 years’ education, entered the terminal phase at around 8 years from death, after which the rate of cognitive decline steepened by −1·70 points per year closer to the time of death (SEM 0·20, p<0·0001) and accelerated by −0·11 (SEM 0·01, p<0·0001). Education was positively associated with the estimated mean MMSE scores before death only in OCTO-Twin (0·43, SEM 0·15; p=0·003) and did not attenuate the rate of terminal decline in either cohort. Interpretation Decline and acceleration of this decline were detectable in both studies before death, with steeper rates of decline observed in the Swedish cohort. However, this process was not lessened by education itself. This work contributes to a better understanding of the transition from the subtle cognitive changes associated with age to those of neurological substance, and the role of education in this decline. Funding The funding sources of this work were the Alzheimer's Society (grant number 144) and the Medical Research Council (unit programme number MC_UU_12019/1)
Gamma-ray bursts and terrestrial planetary atmospheres
We describe results of modeling the effects on Earth-like planets of
long-duration gamma-ray bursts (GRBs) within a few kiloparsecs. A primary
effect is generation of nitrogen oxide compounds which deplete ozone. Ozone
depletion leads to an increase in solar UVB radiation at the surface, enhancing
DNA damage, particularly in marine microorganisms such as phytoplankton. In
addition, we expect increased atmospheric opacity due to buildup of nitrogen
dioxide produced by the burst and enhanced precipitation of nitric acid. We
review here previous work on this subject and discuss recent developments,
including further discussion of our estimates of the rates of impacting GRBs
and the possible role of short-duration bursts.Comment: 12 pages including 5 figures (4 in color). Added discussion of GRB
rates and biological effects. Accepted for publication in New Journal of
Physics, for special issue "Focus on Gamma-Ray Bursts
Therapeutic efficacy of favipiravir against Bourbon virus in mice
Bourbon virus (BRBV) is an emerging tick-borne RNA virus in the orthomyxoviridae family that was discovered in 2014. Although fatal human cases of BRBV have been described, little is known about its pathogenesis, and no antiviral therapies or vaccines exist. We obtained serum from a fatal case in 2017 and successfully recovered the second human infectious isolate of BRBV. Next-generation sequencing of the St. Louis isolate of BRBV (BRBV-STL) showed >99% nucleotide identity to the original reference isolate. Using BRBV-STL, we developed a small animal model to study BRBV-STL tropism in vivo and evaluated the prophylactic and therapeutic efficacy of the experimental antiviral drug favipiravir against BRBV-induced disease. Infection of Ifnar1-/- mice lacking the type I interferon receptor, but not congenic wild-type animals, resulted in uniformly fatal disease 6 to 10 days after infection. RNA in situ hybridization and viral yield assays demonstrated a broad tropism of BRBV-STL with highest levels detected in liver and spleen. In vitro replication and polymerase activity of BRBV-STL were inhibited by favipiravir. Moreover, administration of favipiravir as a prophylaxis or as post-exposure therapy three days after infection prevented BRBV-STL-induced mortality in immunocompromised Ifnar1-/- mice. These results suggest that favipiravir may be a candidate treatment for humans who become infected with BRBV
Evolutionary Conservation of the PA-X Open Reading Frame in Segment 3 of Influenza A Virus
PA-X is a fusion protein of influenza A virus encoded in part from a +1 frameshifted X open reading frame (X-ORF) in segment 3. We show that the X-ORFs of diverse influenza A viruses can be divided into two groups that differ in selection pressure and likely function, reflected in the presence of an internal stop codon and a change in synonymous diversity. Notably, truncated forms of PA-X evolved convergently in swine and dogs, suggesting a strong species-specific effect
Is late-life dependency increasing or not? A comparison of the Cognitive Function and Ageing Studies (CFAS)
Background: Little is known about how the proportions of dependency states have changed between generational cohorts of older people. We aimed to estimate years lived in different dependency states at age 65 years in 1991 and 2011, and new projections of future demand for care. Methods: In this population-based study, we compared two Cognitive Function and Ageing Studies (CFAS I and CFAS II) of older people (aged ≥65 years) who were permanently registered with a general practice in three defined geographical areas (Cambridgeshire, Newcastle, and Nottingham; UK). These studies were done two decades apart (1991 and 2011). General practices provided lists of individuals to be contacted and were asked to exclude those who had died or might die over the next month. Baseline interviews were done in the community and care homes. Participants were stratified by age, and interviews occurred only after written informed consent was obtained. Information collected included basic sociodemographics, cognitive status, urinary incontinence, and self-reported ability to do activities of daily living. CFAS I was assigned as the 1991 cohort and CFAS II as the 2011 cohort, and both studies provided prevalence estimates of dependency in four states: high dependency (24-h care), medium dependency (daily care), low dependency (less than daily), and independent. Years in each dependency state were calculated by Sullivan's method. To project future demands for social care, the proportions in each dependency state (by age group and sex) were applied to the 2014 England population projections. Findings: Between 1991 and 2011, there were significant increases in years lived from age 65 years with low dependency (1·7 years [95% CI 1·0-2·4] for men and 2·4 years [1·8-3·1] for women) and increases with high dependency (0·9 years [0·2-1·7] for men and 1·3 years [0·5-2·1] for women). The majority of men's extra years of life were spent independent (36·3%) or with low dependency (36·3%) whereas for women the majority were spent with low dependency (58·0%), and only 4·8% were independent. There were substantial reductions in the proportions with medium and high dependency who lived in care homes, although, if these dependency and care home proportions remain constant in the future, further population ageing will require an extra 71 215 care home places by 2025. Interpretation: On average older men now spend 2·4 years and women 3·0 years with substantial care needs, and most will live in the community. These findings have considerable implications for families of older people who provide the majority of unpaid care, but the findings also provide valuable new information for governments and care providers planning the resources and funding required for the care of their future ageing populations. Funding: Medical Research Council (G9901400) and (G06010220), with support from the National Institute for Health Research Comprehensive Local research networks in West Anglia and Trent, UK, and Neurodegenerative Disease Research Network in Newcastle, UK
The influence of smoking, sedentary lifestyle and obesity on cognitive impairment-free life expectancy
BACKGROUND Smoking, sedentary lifestyle and obesity are risk factors for mortality and dementia. However, their impact on cognitive impairment-free life expectancy (CIFLE)has not previously been estimated. METHODS Data were drawn from the DYNOPTA dataset which was derived by harmonizing and pooling common measures from five longitudinal ageing studies. Participants for whom the Mini-Mental State Examination was available were included (N¼8111,48.6% men). Data on education, sex, body mass index, smoking and sedentary lifestyle were collected and mortality data were obtained from Government Records via data linkage.Total life expectancy (LE), CIFLE and years spent with cognitive impairment (CILE)were estimated for each risk factor and total burden of risk factors. RESULTS CILE was approximately 2 years for men and 3 years for women, regardless of age. For men and women respectively, reduced LE associated with smoking was 3.82and 5.88 years, associated with obesity was 0.62 and 1.72 years and associated with being sedentary was 2.50 and 2.89 years. Absence of each risk factor was associated with longer LE and CIFLE, but also longer CILE for smoking in women and being sedentary in both sexes. Compared with participants with no risk factors, those with 2þ had shorter CIFLE of up to 3.5 years depending on gender and education level. CONCLUSIONS Population level reductions in smoking, sedentary lifestyle and obesity increase longevity and number of years lived without cognitive impairment. Years lived with cognitive impairment may also increase.This work was supported by a National Health and Medical
Research Council grant # 410215 and by the Australian Research
Council Centre of Excellence in Population Ageing Research
(CE110001029). K.J.A is funded by NHMRC Fellowship
#1002560. C.J. is funded by the AXA Research Fund
Identification of a novel splice variant form of the influenza A virus M2 ion channel with an antigenically distinct ectodomain
Segment 7 of influenza A virus produces up to four mRNAs. Unspliced transcripts encode M1, spliced mRNA2 encodes the M2 ion channel, while protein products from spliced mRNAs 3 and 4 have not previously been identified. The M2 protein plays important roles in virus entry and assembly, and is a target for antiviral drugs and vaccination. Surprisingly, M2 is not essential for virus replication in a laboratory setting, although its loss attenuates the virus. To better understand how IAV might replicate without M2, we studied the reversion mechanism of an M2-null virus. Serial passage of a virus lacking the mRNA2 splice donor site identified a single nucleotide pseudoreverting mutation, which restored growth in cell culture and virulence in mice by upregulating mRNA4 synthesis rather than by reinstating mRNA2 production. We show that mRNA4 encodes a novel M2-related protein (designated M42) with an antigenically distinct ectodomain that can functionally replace M2 despite showing clear differences in intracellular localisation, being largely retained in the Golgi compartment. We also show that the expression of two distinct ion channel proteins is not unique to laboratory-adapted viruses but, most notably, was also a feature of the 1983 North American outbreak of H5N2 highly pathogenic avian influenza virus. In identifying a 14th influenza A polypeptide, our data reinforce the unexpectedly high coding capacity of the viral genome and have implications for virus evolution, as well as for understanding the role of M2 in the virus life cycle
Information security: The case for a global skills framework
The explosive growth of digital communications since the advent of the internet has been accelerated by the evolution of web 2.0 (social computing) and the pervasive availability of mobile computing technologies. This has led to a societal expectation of being ‘always connected’ in our personal and professional lives. The explosive growth has reduced the barriers of distance, time, language and culture, enabling information to be shared by anyone at global scale at a moment’s notice and at negligible cost. It has also brought with it a cornucopia of threats to information security, and spawned a new domain of the IT profession dedicated to protecting the confidentiality, integrity and availability of IT services. The information assurance/information security (IA/IS) domain of the profession lacks a unified and global skills framework with a common taxonomy or consistent method of assessing competence (knowledge, skills, experience and behaviour) at progressive levels. The situation is not helped by the myriad of qualifications, frameworks and awarding and professional bodies operating in the IA/IS arena. Neither is it aided by the widespread overuse of the imprecise word ‘cyber’ as an epithet for all manner of risks, threats, events and measures in the IA/IS domain of IT. The word cyber is popularly and widely used by the press and media to add an aura of deeply technical subject matter and drama to a news story, e.g. cyber security, cyber defence, cyber attack, cyber warfare and cyber bullying, yet nobody can define what it means. For the purposes of clarity, this whitepaper uses the acronym IA/IS throughout and refers to the confidentiality, integrity and availability (CIA) of data and the security of the IT systems and networks that store, retrieve, transmit and process that data. Experts may argue that the subject of information risk should also be in the scope of that definition; in this whitepaper the term IA/IS will suffice to embrace that topic as well
Serum 25-hydroxyvitamin D and cognitive decline in the very old: the Newcastle 85+ Study.
This is the final version of the article. Available from Wiley via the DOI in this record.BACKGROUND AND PURPOSE: Studies investigating the association between 25-hydroxyvitamin D [25(OH)D] and cognition in the very old (85+) are lacking. METHODS: Cross-sectional (baseline) and prospective data (up to 3 years follow-up) from 775 participants in the Newcastle 85+ Study were analysed for global (measured by the Standardized Mini-Mental State Examination) and attention-specific (measured by the attention battery of the Cognitive Drug Research test) cognitive performance in relation to season-specific 25(OH)D quartiles. RESULTS: Those in the lowest and highest season-specific 25(OH)D quartiles had an increased risk of impaired prevalent (1.66, 95% confidence interval 1.06-2.60, P = 0.03; 1.62, 95% confidence interval 1.02-2.59, P = 0.04, respectively) but not incident global cognitive functioning or decline in functioning compared with those in the middle quartiles adjusted for sociodemographic, health and lifestyle confounders. Random effects models showed that participants belonging to the lowest and highest 25(OH)D quartiles, compared with those in the middle quartiles, had overall slower (log-transformed) attention reaction times for Choice Reaction Time (lowest, β = 0.023, P = 0.01; highest, β = 0.021, P = 0.02), Digit Vigilance Task (lowest, β = 0.009, P = 0.05; highest, β = 0.01, P = 0.02) and Power of Attention (lowest, β = 0.017, P = 0.02; highest, β = 0.022, P = 0.002) and greater Reaction Time Variability (lowest, β = 0.021, P = 0.02; highest, β = 0.02, P = 0.03). The increased risk of worse global cognition and attention amongst those in the highest quartile was not observed in non-users of vitamin D supplements/medication. CONCLUSION: Low and high season-specific 25(OH)D quartiles were associated with prevalent cognitive impairment and poorer overall performance in attention-specific tasks over 3 years in the very old, but not with global cognitive decline or incident impairment.This work was supported by the National Institute for Health Research Newcastle Biomedical Research Centre based at Newcastle Hospitals Foundation Trust and Newcastle University (AG). The Newcastle 85+ Study has been funded by the Medical Research Council, Biotechnology and Biological Sciences Research Council and the Dunhill Medical Trust. Additional work has also been funded by the British Heart Foundation, Unilever Corporate Research, Newcastle University and National Health Service (NHS) North of Tyne (Newcastle Primary Care Trust). The views expressed in this paper are those of the authors and not necessarily those of the National Health Service, UK. We acknowledge the operational support of NHS North of Tyne, the local general practitioners and their staff, the research nurses, laboratory technicians, data management and clerical team, as well as many colleagues for their expert advice. Thanks are due especially to the study participants
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