Recombinant A(H6N1)-H274Y avian influenza virus with dual drug resistance does not require permissive mutations to retain the replicative fitness in vitro and in ovo

The possible emergence of drug-resistant avian flu raises concerns over the limited effectiveness of currently approved antivirals (neuraminidase inhibitors - NAIs) in the hypothetical event of a zoonotic spillover. Our study demonstrated that the recombinant avian A(H6N1) viruses showed reduced inhibition (RI) by multiple NAI drugs following the introduction of point mutations found predominantly in the neuraminidase gene (NA) of NAI-resistant human influenza strains (E119V, R292K and H274Y; N2 numbering). Moreover, A(H6N1)-H274Y showed increased replication efficiency in vitro, and a fitness advantage over wild-type (WT) when co-inoculated into embryonated hen's eggs. The results presented in our study together with the zoonotic potential of the A(H6N1) virus as evidenced by the human infection from 2013, highlight the need for enhanced monitoring of NAI resistance-associated signatures in circulating LPAI (low pathogenic avian influenza) globally.

Creating resistance to avian influenza infection through genome editing of the ANP32 gene family

Chickens genetically resistant to avian influenza could prevent future outbreaks. In chickens, influenza A virus (IAV) relies on host protein ANP32A. Here we use CRISPR/Cas9 to generate homozygous gene edited (GE) chickens containing two ANP32A amino acid substitutions that prevent viral polymerase interaction. After IAV challenge, 9/10 edited chickens remain uninfected. Challenge with a higher dose, however, led to breakthrough infections. Breakthrough IAV virus contained IAV polymerase gene mutations that conferred adaptation to the edited chicken ANP32A. Unexpectedly, this virus also replicated in chicken embryos edited to remove the entire ANP32A gene and instead co-opted alternative ANP32 protein family members, chicken ANP32B and ANP32E. Additional genome editing for removal of ANP32B and ANP32E eliminated all viral growth in chicken cells. Our data illustrate a first proof of concept step to generate IAV-resistant chickens and show that multiple genetic modifications will be required to curtail viral escape.

Operational Ontology for Radiation Oncology (OORO): A Professional Society-Based, Multi-Stakeholder Consensus Driven Informatics Standard Supporting Clinical and Research Use of Real-World Data

PURPOSE/OBJECTIVE(S)

There is a critical need for large-scale, multi-institutional "real-world" data to evaluate patient, diagnosis and treatment factors affecting oncology patient outcomes. However, lack of data standardization undermines the potential for automated learning from the vast amount of information routinely archived in electronic health records (EHRs), Radiation Oncology Information Systems and other cancer care databases. As next step to promote data standardization beyond the American Association of Physicists in Medicine (AAPM)'s TG-263 guidance for radiotherapy (RT) nomenclature, the AAPM's Big Data Subcommittee (BDSC) has led an international RT professional society collaboration to develop the Operational Ontology for Radiation Oncology (OORO).

MATERIALS/METHODS

Initiated July 2019 to explore issues that typically compromise formation of large inter- and intra- institutional databases from EHRs, the AAPM's BDSC membership includes representatives from the AAPM, American Society of Radiation Oncology (ASTRO), Canadian Organization of Medical Physicists (COMP), Canadian Association of Radiation Oncology (CARO), European Society of Therapeutic Radiation Oncology (ESTRO) and clinical trials experts from NRG Oncology. Multiple external stakeholders were engaged, including government agencies, vendors and RT community members through the iterative and consensus-driven approach to OORO development.

RESULTS

The OORO includes 42 key elements, 359 attributes, 144 value sets, and 155 relationships, ranked for priority of implementation based on clinical significance, likelihood of availability in EHRs, or ability to modify routine clinical processes to permit aggregation. The initial version of OORO includes many disease-site independent concepts common for all cancer patients and a smaller set specific for prostate cancer. The OORO development methodology is currently being applied/adapted to include additional disease site-specific concepts beginning with head and neck cancers.

CONCLUSION

The first of its kind in radiation oncology, the OORO is a professional society-based, multi-stakeholder, consensus driven informatics standard. The iterative and collaborative approach to ontology development and refinement aims to ensure that OORO serves as a « living » guidance document, facilitating incremental expansion of data elements over time, as disease site-specific standards are set and RT concepts evolve. Supporting construction of comprehensive "real-world" datasets and application of advanced analytic techniques, including artificial intelligence (AI), OORO holds the potential to revolutionize patient management and improve outcomes.

Pneumothorax Trends from 2010-2020 from a Large-Volume Pleural Unit

INTRODUCTION

Previous studies in 2018 and 2022 have suggested increasing inpatient burden of pneumothorax and widespread variation in management. Local trends have never been elucidated. Northumbria Healthcare NHS Foundation Trust (NHCT) has a well-established pleural service, serving just over 600,000. Thus, we set up a local retrospective study to look at trends in pneumothorax presentation, management strategies, length of stay, and recurrence.

METHODS

A coding search for 'pneumothorax' was performed for all patients attending NHCT between 2010 and 2020 was performed with local Caldicott approval. A total of 1840 notes were analysed to exclude iatrogenic, traumatic, and paediatric events. After excluding those cases, 580 remained for further analysis, consisting of 183 primary pneumothoraces (PSP) and 397 secondary pneumothoraces (SSP).

RESULTS

Median age for PSP was 26.5 years (IQR 17) with 69% male, and for SSP 68 years (IQR 11.5), 62% male; 23.5% of PSP and 8.6% of SSP were never smokers. The proportion of smokers and ex-smokers has not really changed over time: > 65% every year have been smokers or ex-smokers. Yearly pneumothorax incidence shows a downward trend for PSP but upwards for SSP. Median length of stay (LoS) for PSP was 2 days (IQR 2), and SSP 5 days (IQR 8), with a clear downward trend. From 2010 to 2015 > 50% PSP were managed with drain, but in 2019-2020 at least 50% managed conservatively, with a significant reduction in aspiration. Trends of recurrence for PSP are increasing, whereas for SSP is decreasing. Seventy-six (20 PSP, 56 SSP) went for surgery at the index time with 5.3% recurrence (20% recurrence in those without surgery).

CONCLUSIONS

This is the first known analysis of pneumothorax trends in a large trust in the northeast of England. The data in this study have certain limitations, including the lack of information on the size of pneumothorax and frailty indicators that may influence the decision for conservative management. Additionally, there is a reliance on clinical coding, which can introduce potential inaccuracies, and not all patient notes were accessible for analysis. Updated larger datasets should help elucidate trends better.

TRIM5α restricts poxviruses and is antagonized by CypA and the viral protein C6

Human tripartite motif protein 5α (TRIM5α) is a well-characterized restriction factor for some RNA viruses, including HIV1-5; however, reports are limited for DNA viruses6,7. Here we demonstrate that TRIM5α also restricts orthopoxviruses and, via its SPRY domain, binds to the orthopoxvirus capsid protein L3 to diminish virus replication and activate innate immunity. In response, several orthopoxviruses, including vaccinia, rabbitpox, cowpox, monkeypox, camelpox and variola viruses, deploy countermeasures. First, the protein C6 binds to TRIM5 via the RING domain to induce its proteasome-dependent degradation. Second, cyclophilin A (CypA) is recruited via interaction with the capsid protein L3 to virus factories and virions to antagonize TRIM5α; this interaction is prevented by cyclosporine A (CsA) and the non-immunosuppressive derivatives alisporivir and NIM811. Both the proviral effect of CypA and the antiviral effect of CsA are dependent on TRIM5α. CsA, alisporivir and NIM811 have antiviral activity against orthopoxviruses, and because these drugs target a cellular protein, CypA, the emergence of viral drug resistance is difficult. These results warrant testing of CsA derivatives against orthopoxviruses, including monkeypox and variola.

Statistical properties of sketching algorithms

Sketching is a probabilistic data compression technique that has been largely developed by the computer science community. Numerical operations on big datasets can be intolerably slow; sketching algorithms address this issue by generating a smaller surrogate dataset. Typically, inference proceeds on the compressed dataset. Sketching algorithms generally use random projections to compress the original dataset, and this stochastic generation process makes them amenable to statistical analysis. We argue that the sketched data can be modelled as a random sample, thus placing this family of data compression methods firmly within an inferential framework. In particular, we focus on the Gaussian, Hadamard and Clarkson-Woodruff sketches and their use in single-pass sketching algorithms for linear regression with huge samples. We explore the statistical properties of sketched regression algorithms and derive new distributional results for a large class of sketching estimators. A key result is a conditional central limit theorem for data-oblivious sketches. An important finding is that the best choice of sketching algorithm in terms of mean squared error is related to the signal-to-noise ratio in the source dataset. Finally, we demonstrate the theory and the limits of its applicability on two datasets.

Patients’ perspectives on factors affecting their involvement in decision-making on oral anticoagulant therapy for stroke prevention in non-valvular atrial fibrillation

Introduction

Acknowledging patients’ preferences and addressing their concerns is thought to improve patients’ satisfaction with consultations, resulting in improved adherence and health benefits [1]. Adherence to oral anticoagulant (OA) therapy in non-valvular atrial fibrillation (NVAF) is crucial to prevent AF-related strokes. Previous research on anticoagulation in NVAF indicated that decision-making was dominated by prescribers, but patients offered several therapy options reported being involved [2]. Identifying the patient’s perspective on factors affecting their involvement could help to deliver more patient-centred care in the management of AF.

Aim

To explore patients’ perspectives and experiences concerning factors affecting their involvement in decision-making about OA therapy for stroke prevention in NVAF.

Methods

Semi-structured face-to-face interviews were conducted with patients in three health economies in the North of England between August 2018 and April 2019. An interview topic guide based on narrative review findings [2] was developed and refined by a Patient and Public Involvement (PPI) group to ensure clarity. Theoretical sampling was used to recruit adults (>18 years) diagnosed with NVAF, prescribed OA (vitamin K antagonist or direct oral anticoagulant (DOAC)), and able to give written consent. Up to 30 potential participants were approached by a member of their direct care team (nurse or pharmacist) in secondary and primary care anticoagulation or arrhythmia clinics. PPI members recruited patients from a local patient support group. Data collection continued until data saturation was achieved. Audio recorded interviews were transcribed verbatim and analysed using the Framework method.

Results

A total of 21 patient with median (IQR) age of 73 years (65–78 years) were interviewed. Eleven patients took DOACs. The median (IQR) time of taking OA was 3 years (4 weeks-7 years), warfarin 7 years (3–9 years) and DOAC 1 year (4 weeks-4 years). Interviews lasted between 15 and 48 minutes (average 27 minutes). Three themes were identified during analysis (Figure 1). Patients described therapy decisions being made by just the clinician, jointly with the clinician, and in few cases by the patient alone. The lack of involvement resulted from patients perceiving that there was only a choice between accepting and refusing the therapy, and clinician’s role was to make decisions. Limited consultation times, lack of continuous relationship with a clinician and knowledge about OAs options discouraged patients from being involved and some patients reported difficulties with the prescribed therapy. Patients that were involved considered safety of therapy options and impact on daily life.

Conclusions

Limited consultation time, patient’s perception of clinician’s role, quality of patient-clinician relationship, and patients’ awareness of therapy options were main factors influencing the level of patient involvement in the decision-making. Support from both organisation and clinicians (e.g., longer consultations, availability of different therapy options) is needed to facilitate greater patient involvement, which could prevent difficulties encountered by some patients. The main strength of this study was recruitment of participants from three health economies differing in anticoagulation service provision models, which enabled greater insight into potential barriers. However, the sample was lacking ethnic diversity and could have potential of recall bias.

References

1. Shay LA and Lafata JE. (2015). Where is the evidence? A systematic review of shared decision making and patient outcomes. Medical Decision Making. 35 (1): 114–131.

2. Medlinskiene K, Petty D, Richardson S and Stirling K. (2018) Are patients with non-valvular atrial fibrillation involved in decision-making about oral anticoagulants? A literature review. International Journal of Pharmacy Practice. 26 (Suppl. 1): 42–43.

The molecular landscape and associated clinical experience in infant medulloblastoma: prognostic significance of second-generation subtypes

AIMS

Biomarker-driven therapies have not been developed for infant medulloblastoma (iMB). We sought to robustly sub-classify iMB, and proffer strategies for personalized, risk-adapted therapies.

METHODS

We characterized the iMB molecular landscape, including second-generation subtyping, and the associated retrospective clinical experience, using large independent discovery/validation cohorts (n = 387).

RESULTS

iMB_Grp3 (42%) and iMB_SHH (40%) subgroups predominated. iMB_Grp3 harboured second-generation subtypes II/III/IV. Subtype II strongly associated with large-cell/anaplastic pathology (LCA; 23%) and MYC amplification (19%), defining a very-high-risk group (0% 10yr overall survival (OS)), which progressed rapidly on all therapies; novel approaches are urgently required. Subtype VII (predominant within iMB_Grp4 ) and subtype IV tumours were standard risk (80% OS) using upfront CSI-based therapies; randomized-controlled trials of upfront radiation-sparing and/or second-line radiotherapy should be considered. Seventy-five per cent of iMB_SHH showed DN/MBEN histopathology in discovery and validation cohorts (P < 0.0001); central pathology review determined diagnosis of histological variants to WHO standards. In multivariable models, non-DN/MBEN pathology was associated significantly with worse outcomes within iMB_SHH . iMB_SHH harboured two distinct subtypes (iMB_SHH-I/II ). Within the discriminated favourable-risk iMB_SHH DN/MBEN patient group, iMB_SHH-II had significantly better progression-free survival than iMB_SHH-I , offering opportunities for risk-adapted stratification of upfront therapies. Both iMB_SHH-I and iMB_SHH-II showed notable rescue rates (56% combined post-relapse survival), further supporting delay of irradiation. Survival models and risk factors described were reproducible in independent cohorts, strongly supporting their further investigation and development.

CONCLUSIONS

Investigations of large, retrospective cohorts have enabled the comprehensive and robust characterization of molecular heterogeneity within iMB. Novel subtypes are clinically significant and subgroup-dependent survival models highlight opportunities for biomarker-directed therapies.

Relative Effectiveness of Selenite Cystine Broth, Tetrathionate Broth, and Rappaport-Vassiliadis Medium for Recovery of Salmonella spp. from Raw Flesh, Highly Contaminated Foods, and Poultry Feed: Collaborative Study

A collaborative study was performed in 18 laboratories to validate use of Rappaport-Vassiliadis (RV) medium in the standard culture method for recovery of Salmonella spp. from raw, highly contaminated foods and poultry feed. RV medium made from its individual ingredients and incubated at 42�C was compared with selenite cystine (SC) broth incubated at 35�C and tetrathionate (TT) broth incubated at 35� and 43�C for effectiveness in recovery of Salmonella spp. Four artificially contaminated foods (oysters, frog legs, mushrooms, and shrimp) and poultry feed and one naturally contaminated food (chicken) were analyzed. The artificially contaminated foods were inoculated with single serovars of Salmonella at target levels of 0.04 colony-forming units (CFU)/g for the low level and 0.4 CFU/g for the high level. For analysis of 1125 test portions, RV medium (42�C) recovered Salmonellairom 409 test portions; TT (43�C), from 368 test portions; TT (35�C), from 310 test portions; and SC (35�C), from 334 test portions. Overall, RV medium was comparable with or better than other selective enrichments for recovery of Salmonella from the foods in this study, except mushrooms. From mushrooms, SC broth (35�C) recovered more positive test portions than did RV medium (42�C) and TT broth (43�C). The method for detection of Salmonella in raw, highly contaminated foods and

Fast nonadiabatic dynamics of many-body quantum systems

Modeling many-body quantum systems with strong interactions is one of the core challenges of modern physics. A range of methods has been developed to approach this task, each with its own idiosyncrasies, approximations, and realm of applicability. However, there remain many problems that are intractable for existing methods. In particular, many approaches face a huge computational barrier when modeling large numbers of coupled electrons and ions at finite temperature. Here, we address this shortfall with a new approach to modeling many-body quantum systems. On the basis of the Bohmian trajectory formalism, our new method treats the full particle dynamics with a considerable increase in computational speed. As a result, we are able to perform large-scale simulations of coupled electron-ion systems without using the adiabatic Born-Oppenheimer approximation.

Is there a role for pentoxifylline and tocopherol in the management of advanced osteoradionecrosis of the jaws with pathological fractures? Case reports and review of the literature

Osteoradionecrosis (ORN) is an infrequent but serious complication of radiotherapy, especially in the head and neck region. It is a slowly progressive condition, with management in the early stages focused on symptom control, and surgery usually reserved for advanced ORN. However, established ORN is difficult to treat. The role of hyperbaric oxygen therapy has recently been contested. The use of pentoxifylline in the management of ORN was first described by Delanian in 2004, but its benefits have not been replicated in other studies. In cases of advanced ORN with pathological fractures, many centres still advocate surgical resection and reconstruction. However, in this group of patients who often have multiple medical comorbidities, many of whom have previously undergone significant surgery, a resective plan is not always ideal. This paper presents two successful cases of bony union after the use of pentoxifylline and tocopherol to manage grade III ORN of the mandible. Both patients had pathological fractures and orocutaneous fistulas and were deemed unsuitable for surgery. The possible reasons for the success of pentoxifylline and tocopherol are discussed, and a review of the current literature evidence of similar cases is presented. Pentoxifylline and tocopherol should be considered for the management of advanced ORN where surgical management is not appropriate.

A two-step method for variable selection in the analysis of a case-cohort study

Background

Accurate detection and estimation of true exposure-outcome associations is important in aetiological analysis; when there are multiple potential exposure variables of interest, methods for detecting the subset of variables most likely to have true associations with the outcome of interest are required. Case-cohort studies often collect data on a large number of variables which have not been measured in the entire cohort (e.g. panels of biomarkers). There is a lack of guidance on methods for variable selection in case-cohort studies.

Methods

We describe and explore the application of three variable selection methods to data from a case-cohort study. These are: (i) selecting variables based on their level of significance in univariable (i.e. one-at-a-time) Prentice-weighted Cox regression models; (ii) stepwise selection applied to Prentice-weighted Cox regression; and (iii) a two-step method which applies a Bayesian variable selection algorithm to obtain posterior probabilities of selection for each variable using multivariable logistic regression followed by effect estimation using Prentice-weighted Cox regression.

Results

Across nine different simulation scenarios, the two-step method demonstrated higher sensitivity and lower false discovery rate than the one-at-a-time and stepwise methods. In an application of the methods to data from the EPIC-InterAct case-cohort study, the two-step method identified an additional two fatty acids as being associated with incident type 2 diabetes, compared with the one-at-a-time and stepwise methods.

Conclusions

The two-step method enables more powerful and accurate detection of exposure-outcome associations in case-cohort studies. An R package is available to enable researchers to apply this method.

Characterization of the Mercury pulsed power x-ray source spectrum using multichannel density aerogel Cherenkov detectors

The Aerogel Cherenkov Detector for Cygnus (ACD/C) is a time-dependent, x-ray spectral detector that uses SiO₂ aerogels spanning an index of refraction (n = 1.02-1.07) corresponding to a 1.1-2.3 MeV x-ray energy threshold. The ACD/C was developed for pulsed power x-ray sources like Cygnus located at the Nevada National Site and Mercury located at the Naval Research Laboratory (NRL). Aerogels sit between the measurement capabilities of gas (>2 MeV) and solids such as fused silica (>0.3 MeV). The detector uses an aluminum converter to Compton scatter incoming x-rays and create relativistic electrons, which produce Cherenkov light in an aerogel or a fused silica medium. The ACD/C was fielded at the NRL when Mercury was tuned to produce up to 4.8 MeV endpoint bremsstrahlung. Despite a high radiation and electromagnetic interference background, the ACD/C was able to achieve high signal over noise across five aerogel densities and fused silica, including a signal to noise for a 1.1 MeV aerogel threshold. Previous experiments at Cygnus observed a signal that was comparable to the noise (1×) at the same threshold. The ACD/C observed time-resolved rise and fall times for different energy thresholds of the photon spectrum. Monte Carlo simulations of the ACD/C's aerogel response curves were folded with a simulation of Mercury's photon energy spectrum and agree within the error to the observed result.

Goal Attainment Scaling for haemophilia (GAS-Hēm): testing the feasibility of a new patient-centric outcome measure in people with haemophilia

INTRODUCTION

To address the need for a patient-reported outcome that can measure clinically and personally meaningful change in people with haemophilia (PwH) on prophylaxis, an approach based on Goal Attainment Scaling (GAS) was developed: the GAS-Hēm.

AIM

To establish real-world feasibility of GAS-Hēm in PwH.

METHODS

Patients aged 5-65 years were enroled from four North American centres for a 12-week study. The primary outcome was the proportion of participants who completed GAS-Hēm interviews at baseline, 6 and 12 weeks. GAS-Hēm scores were obtained by subject- and clinician-rated goal attainment at Weeks 6 and 12, and compared with quality of life (QoL) measures and annualized bleed rate (ABR) for construct validity. Goals were evaluated qualitatively for content validity. Responsiveness was calculated using standardized response means (SRM).

RESULTS

Forty-two participants set 63 goals. Participants preferred to define (37/63) their own goals or further individualize (23/63) from the GAS-Hēm menu. Thirty of the 37 self-defined goals were matched to goals on the GAS-Hēm menu. The most common goal areas were: weight, exercise and nutrition (n = 17); leisure activities (n = 8); and joint problems (n = 7). Both participant- and clinician-rated GAS-Hēm scores at 6 weeks (n = 40) and 12 weeks (n = 41) demonstrated satisfactory goal attainment (SRM [subject-rated] at 12 weeks for adult and paediatric groups was 1.25 and 1.16, respectively). Correlations of GAS-Hēm scores with QoL measures and ABR were uniformly small.

CONCLUSION

GAS-Hēm was feasible and tapped constructs not captured by ABR or QoL measures.

The species origin of the cellular microenvironment influences markers of beta cell fate and function in EndoC-βH1 cells

Interaction between islet cell subtypes and the extracellular matrix influences beta-cell function in mammals. The tissue architecture of rodent islets is very different to that of human islets; cell-to-cell communication and interaction with the extracellular matrix may vary between species. In this work, we have compared the responses of the human EndoC-βH1 cell line to non-human and human-derived growth matrices in terms of growth morphology, gene expression and glucose-stimulated insulin secretion (GSIS). EndoC-βH1 cells demonstrated a greater tendency to form cell clusters when cultured in a human microenvironment and exhibited reduced alpha cell markers at the mRNA level; mean expression difference - 0.23 and - 0.51; p = 0.009 and 0.002 for the Aristaless-related homeobox (ARX) and Glucagon (GCG) genes respectively. No differences were noted in the protein expression of mature beta cell markers such as Pdx1 and NeuroD1 were noted in EndoC-βH1 cells grown in a human microenvironment but cells were however more sensitive to glucose (4.3-fold increase in insulin secretion following glucose challenge compared with a 1.9-fold increase in cells grown in a non-human microenvironment; p = 0.0003). Our data suggests that the tissue origin of the cellular microenvironment has effects on the function of EndoC-βH1 cells in vitro, and the use of a more human-like culture microenvironment may bring benefits in terms of increased physiological relevance.

Weibull regression with Bayesian variable selection to identify prognostic tumour markers of breast cancer survival

As data-rich medical datasets are becoming routinely collected, there is a growing demand for regression methodology that facilitates variable selection over a large number of predictors. Bayesian variable selection algorithms offer an attractive solution, whereby a sparsity inducing prior allows inclusion of sets of predictors simultaneously, leading to adjusted effect estimates and inference of which covariates are most important. We present a new implementation of Bayesian variable selection, based on a Reversible Jump MCMC algorithm, for survival analysis under the Weibull regression model. A realistic simulation study is presented comparing against an alternative LASSO-based variable selection strategy in datasets of up to 20,000 covariates. Across half the scenarios, our new method achieved identical sensitivity and specificity to the LASSO strategy, and a marginal improvement otherwise. Runtimes were comparable for both approaches, taking approximately a day for 20,000 covariates. Subsequently, we present a real data application in which 119 protein-based markers are explored for association with breast cancer survival in a case cohort of 2287 patients with oestrogen receptor-positive disease. Evidence was found for three independent prognostic tumour markers of survival, one of which is novel. Our new approach demonstrated the best specificity.

Wnt4 antagonises Wnt3a mediated increases in growth and glucose stimulated insulin secretion in the pancreatic beta-cell line, INS-1

The Wnt signalling pathway in beta-cells has been linked to the development of type 2 diabetes. Investigating the impact of a non-canonical Wnt ligand, Wnt4, on beta-cell function we found that in INS-1 cells, Wnt4 was able to completely block Wnt3a stimulated cell growth and insulin secretion. However, despite high levels of Wnt4 protein being detected in INS-1 cells, reducing the expression of Wnt4 had no impact on cell growth or Wnt3a signalling. As such, the role of the endogenously expressed Wnt4 in beta-cells is unclear, but the data showing that Wnt4 can act as a negative regulator of canonical Wnt signalling in beta-cells suggests that this pathway could be a potential target for modulating beta-cell function.

Application of neurite orientation dispersion and density imaging (NODDI) to a tau pathology model of Alzheimer's disease

Increased hyperphosphorylated tau and the formation of intracellular neurofibrillary tangles are associated with the loss of neurons and cognitive decline in Alzheimer's disease, and related neurodegenerative conditions. We applied two diffusion models, diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI), to in vivo diffusion magnetic resonance images (dMRI) of a mouse model of human tauopathy (rTg4510) at 8.5 months of age. In grey matter regions with the highest degree of tau burden, microstructural indices provided by both NODDI and DTI discriminated the rTg4510 (TG) animals from wild type (WT) controls; however only the neurite density index (NDI) (the volume fraction that comprises axons or dendrites) from the NODDI model correlated with the histological measurements of the levels of hyperphosphorylated tau protein. Reductions in diffusion directionality were observed when implementing both models in the white matter region of the corpus callosum, with lower fractional anisotropy (DTI) and higher orientation dispersion (NODDI) observed in the TG animals. In comparison to DTI, histological measures of tau pathology were more closely correlated with NODDI parameters in this region. This in vivo dMRI study demonstrates that NODDI identifies potential tissue sources contributing to DTI indices and NODDI may provide greater specificity to pathology in Alzheimer's disease.

•

We analyzed the microstructural changes in rTg4510 and wild type mice at 8.5 months.

•

We correlated microstructural findings with histological measures of tau burden

•

We compare two diffusion MR models: DTI and NODDI.

•

Both models revealed changes in tissue microstructure due to tau pathology.

•

The NODDI metrics demonstrated a good correlation with histological measures of tau burden.

The effectiveness of tobacco control television advertisements in increasing the prevalence of smoke-free homes

BACKGROUND

There is considerable evidence that tobacco control mass media campaigns can change smoking behaviour. In the UK, campaigns over the last decade have contributed to declines in smoking prevalence and been associated with falls in cigarette consumption among continuing smokers. However, it is less evident whether such campaigns can also play a role in changing smokers' behaviour in relation to protecting others from the harmful effects of their smoking in the home. We investigated whether exposure to English televised tobacco control campaigns, and specifically campaigns targeting second hand smoking, is associated with smokers having a smoke-free home.

METHODS

We used repeated cross-sectional national survey data on 9872 households which participated in the Health Survey for England between 2004 and 2010, with at least one adult current smoker living in the household. Exposure to all government-funded televised tobacco control campaigns, and to those specifically with a second hand smoking theme, was quantified in Gross Rating Points (GRPs), an average per capita measure of advert exposure where 100 GRPs indicates 100 % of adults exposed once or 50 % twice. Our outcome was self-reported presence of a smoke-free home (where no one smokes in the home on most days). Analysis used generalised additive models, controlling for individual factors and temporal trends.

RESULTS

There was no association between monthly televised campaigns overall and the probability of having a smoke-free home. However, exposure to campaigns specifically targeting second hand smoke was associated with increased odds of a smoke-free home in the following month (odds ratio per additional 100 GRPs, 1.07, 95 % CI 1.01 to 1.13), though this association was not seen at other lags. These effects were not modified by socio-economic status or by presence of a child in the home.

CONCLUSIONS

Our findings provide tentative evidence that mass media campaigns specifically focussing on second hand smoke may be effective in reducing smoking in the home, and further evaluation of campaigns of this type is needed. General tobacco control campaigns in England, which largely focus on promoting smoking cessation, do not impact on smoke-free homes over and above their direct effect at reducing smoking.

In vivo imaging of tau pathology using multi-parametric quantitative MRI

As the number of people diagnosed with Alzheimer's disease (AD) reaches epidemic proportions, there is an urgent need to develop effective treatment strategies to tackle the social and economic costs of this fatal condition. Dozens of candidate therapeutics are currently being tested in clinical trials, and compounds targeting the aberrant accumulation of tau proteins into neurofibrillary tangles (NFTs) are the focus of substantial current interest. Reliable, translatable biomarkers sensitive to both tau pathology and its modulation by treatment along with animal models that faithfully reflect aspects of the human disease are urgently required. Magnetic resonance imaging (MRI) is well established as a valuable tool for monitoring the structural brain changes that accompany AD progression. However the descent into dementia is not defined by macroscopic brain matter loss alone: non-invasive imaging measurements sensitive to protein accumulation, white matter integrity and cerebral haemodynamics probe distinct aspects of AD pathophysiology and may serve as superior biomarkers for assessing drug efficacy. Here we employ a multi-parametric array of five translatable MRI techniques to characterise the in vivo pathophysiological phenotype of the rTg4510 mouse model of tauopathy (structural imaging, diffusion tensor imaging (DTI), arterial spin labelling (ASL), chemical exchange saturation transfer (CEST) and glucose CEST). Tau-induced pathological changes included grey matter atrophy, increased radial diffusivity in the white matter, decreased amide proton transfer and hyperperfusion. We demonstrate that the above markers unambiguously discriminate between the transgenic group and age-matched controls and provide a comprehensive profile of the multifaceted neuropathological processes underlying the rTg4510 model. Furthermore, we show that ASL and DTI techniques offer heightened sensitivity to processes believed to precede detectable structural changes and, as such, provides a platform for the study of disease mechanisms and therapeutic intervention.

Rate of cyp51A mutation in Aspergillus fumigatus among lung transplant recipients with targeted prophylaxis

OBJECTIVES

The most common mechanism of azole (itraconazole and voriconazole) resistance in Aspergillus fumigatus is a mutation at the cyp51A locus. The aim of our study was to determine the rate of cyp51A mutations in lung transplant recipients (LTR) undergoing targeted antifungal prophylaxis with 12 weeks of voriconazole.

METHODS

We conducted a prospective study that included 22 LTR with A. fumigatus between October 2008 and November 2011. Of those, 10 LTR were colonized with A. fumigatus and 12 had invasive pulmonary aspergillosis.

RESULTS

Four patients were found to have A. fumigatus isolates with a cyp51A mutation, two had colonization and two had invasive pulmonary aspergillosis. The remaining 18 LTR had WT cyp51A A. fumigatus isolates. All A. fumigatus isolates (except one due to mixed growth) were tested for antifungal susceptibility. A total of nine LTR were exposed to azoles prior to A. fumigatus isolation for a median duration of 249 (IQR 99-524) days. Azole exposure preceded the isolation of two mutant isolates and seven WT isolates. None of the cyp51A mutant isolates conferred phenotypic resistance to azoles.

CONCLUSIONS

Targeted antifungal prophylaxis in LTR did not lead to cyp51A resistance mutations in this cohort. Data on larger cohorts who receive universal antifungal prophylaxis are needed.

Effectiveness of tobacco control television advertisements with different types of emotional content on tobacco use in England, 2004-2010

AIM

To examine the effects of tobacco control television advertisements with positive and negative emotional content on adult smoking prevalence and cigarette consumption.

DESIGN

Analysis of monthly cross-sectional surveys using generalised additive models.

SETTING

England.

PARTICIPANTS

60 000 adults aged 18 years or over living in England and interviewed in the Opinions and Lifestyle Survey from 2004 to 2010.

MEASUREMENTS

Current smoking status, daily cigarette consumption, tobacco control gross rating points (GRPs-a measure of per capita advertising exposure), cigarette costliness, concurrent tobacco control policies, sociodemographic variables.

RESULTS

After adjusting for cigarette costliness, other tobacco control policies and individual characteristics, we found that a 400-point increase in positive emotive GRPs was associated with 7% lower odds of smoking (odds ratio (OR) 0.93, 95% CI 0.87 to 0.98) 1 month later and a similar increase in negative emotive GRPs was significantly associated with 4% lower odds of smoking (OR 0.96, 95% CI 0.92 to 0.999) 2 months later. An increase in negative emotive GRPs from 0 to 400 was also associated with a significant 3.3% (95% CI 1.1 to 5.6) decrease in average cigarette consumption. There was no evidence that the association between positive emotive GRPs and the outcomes differed depending on the intensity of negative emotive GRPs (and vice versa).

CONCLUSIONS

This is the first study to explore the effects of campaigns with different types of emotive content on adult smoking prevalence and consumption. It suggests that both types of campaign (positive and negative) are effective in reducing smoking prevalence, whereas consumption among smokers was only affected by campaigns evoking negative emotions.