Timing of radiotherapy (RT) after radical prostatectomy (RP): long-term outcomes in the RADICALS-RT trial (NCT00541047)

BACKGROUND

The optimal timing of radiotherapy (RT) after radical prostatectomy for prostate cancer has been uncertain. RADICALS-RT compared efficacy and safety of adjuvant RT versus an observation policy with salvage RT for prostate-specific antigen (PSA) failure.

PATIENTS AND METHODS

RADICALS-RT was a randomised controlled trial enrolling patients with ≥1 risk factor (pT3/4, Gleason 7-10, positive margins, preoperative PSA≥10 ng/ml) for recurrence after radical prostatectomy. Patients were randomised 1:1 to adjuvant RT ('Adjuvant-RT') or an observation policy with salvage RT for PSA failure ('Salvage-RT') defined as PSA≥0.1 ng/ml or three consecutive rises. Stratification factors were Gleason score, margin status, planned RT schedule (52.5 Gy/20 fractions or 66 Gy/33 fractions) and treatment centre. The primary outcome measure was freedom-from-distant-metastasis (FFDM), designed with 80% power to detect an improvement from 90% with Salvage-RT (control) to 95% at 10 years with Adjuvant-RT. Secondary outcome measures were biochemical progression-free survival, freedom from non-protocol hormone therapy, safety and patient-reported outcomes. Standard survival analysis methods were used; hazard ratio (HR)<1 favours Adjuvant-RT.

RESULTS

Between October 2007 and December 2016, 1396 participants from UK, Denmark, Canada and Ireland were randomised: 699 Salvage-RT, 697 Adjuvant-RT. Allocated groups were balanced with a median age of 65 years. Ninety-three percent (649/697) Adjuvant-RT reported RT within 6 months after randomisation; 39% (270/699) Salvage-RT reported RT during follow-up. Median follow-up was 7.8 years. With 80 distant metastasis events, 10-year FFDM was 93% for Adjuvant-RT and 90% for Salvage-RT: HR=0.68 [95% confidence interval (CI) 0.43-1.07, P=0.095]. Of 109 deaths, 17 were due to prostate cancer. Overall survival was not improved (HR=0.980, 95% CI 0.667-1.440, P=0.917). Adjuvant-RT reported worse urinary and faecal incontinence 1 year after randomisation (P=0.001); faecal incontinence remained significant after 10 years (P=0.017).

CONCLUSION

Long-term results from RADICALS-RT confirm adjuvant RT after radical prostatectomy increases the risk of urinary and bowel morbidity, but does not meaningfully improve disease control. An observation policy with salvage RT for PSA failure should be the current standard after radical prostatectomy.

TRIAL IDENTIFICATION

RADICALS, RADICALS-RT, ISRCTN40814031, NCT00541047.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Bluish-white Light-emitting 2D Sheets of Lead-free Perovskite Cesium Titanium Bromide (CsTiBr3) by a Two-stage Deposition Technique

Bluish-white light-emitting materials are commonly used in LED lighting because they produce natural-looking light. Here we report the photoluminescent emission (PL) of novel, two-dimensional lead-free CsTiBr3 perovskite prepared via a two-stage deposition process. The formation of two-dimensional nanosheets of CsTiBr3 perovskite is confirmed by XRD, EDAX, and FESEM analysis. The height of the cesium bromide thin film substrate from the titanium bromide vapor source plays an important role in the formation of two-dimensional CsTiBr3. The CsTiBr3 perovskite nanosheets exhibit unique exciton- luminescence at 440 nm and self-trapped exciton emission at 595 nm which are the characteristics of two-dimensional halide structure, along with the band-to-band emission at 400 nm at an excitation wavelength of 340 nm. The resulting bluish-white light PL emission makes two-dimensional CsTiBr3 perovskite an alternative material to the traditional lead-based perovskite in LEDs, display technology, solid-state lighting, and various optoelectronic devices, addressing environmental concerns.

Natural cubic splines for the analysis of Alzheimer's clinical trials

Mixed model repeated measures (MMRM) is the most common analysis approach used in clinical trials for Alzheimer's disease and other progressive diseases measured with continuous outcomes over time. The model treats time as a categorical variable, which allows an unconstrained estimate of the mean for each study visit in each randomized group. Categorizing time in this way can be problematic when assessments occur off-schedule, as including off-schedule visits can induce bias, and excluding them ignores valuable information and violates the intention to treat principle. This problem has been exacerbated by clinical trial visits which have been delayed due to the COVID19 pandemic. As an alternative to MMRM, we propose a constrained longitudinal data analysis with natural cubic splines that treats time as continuous and uses test version effects to model the mean over time. Compared to categorical-time models like MMRM and models that assume a proportional treatment effect, the spline model is shown to be more parsimonious and precise in real clinical trial datasets, and has better power and Type I error in a variety of simulation scenarios.

The contribution of dynamics to macaque body and face patch responses

Previous functional imaging studies demonstrated body-selective patches in the primate visual temporal cortex, comparing activations to static bodies and static images of other categories. However, the use of static instead of dynamic displays of moving bodies may have underestimated the extent of the body patch network. Indeed, body dynamics provide information about action and emotion and may be processed in patches not activated by static images. Thus, to map with fMRI the full extent of the macaque body patch system in the visual temporal cortex, we employed dynamic displays of natural-acting monkey bodies, dynamic monkey faces, objects, and scrambled versions of these videos, all presented during fixation. We found nine body patches in the visual temporal cortex, starting posteriorly in the superior temporal sulcus (STS) and ending anteriorly in the temporal pole. Unlike for static images, body patches were present consistently in both the lower and upper banks of the STS. Overall, body patches showed a higher activation by dynamic displays than by matched static images, which, for identical stimulus displays, was less the case for the neighboring face patches. These data provide the groundwork for future single-unit recording studies to reveal the spatiotemporal features the neurons of these body patches encode. These fMRI findings suggest that dynamics have a stronger contribution to population responses in body than face patches.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Alzheimer’s Disease Clinical Trial Research Adaptation Following COVID-19 Pandemic Onset: National Sample of Alzheimer’s Clinical Trial Consortium Sites

Background

The COVID-19 pandemic created challenges in clinical research operations that required immediate and lasting changes.

Ojbectives

The purpose of this study was to explore adaptations to clinical trial research due to COVID-19 and develop a theoretical framework of emergent strategies related to pandemic mitigation in a national network of Alzheimer’s disease clinical trial sites.

Design

This qualitative study used a grounded theory approach including semi-structured interviews, constant comparative methods, and multi-level, iterative coding.

Participants

Twenty-six member sites of the Alzheimer’s Clinical Trial Consortium participated with a total of 49 participants.

Results

Findings demonstrate processes of adaptation following COVID-19 onset including establishing safety as priority, focus on scientific preservation, accommodations (creating policies, leadership mindset, maintaining operations, and determining research procedures), and evaluation of changes throughout the course of the pandemic. Communication and maintaining integrity were vital throughout these processes.

Conclusion

Processes of accommodation among clinical research sites during the pandemic provide critical insights and direction for future clinical trials development and emergent methods in Alzheimer’s disease and other therapeutic areas.

Sensitivity of the Preclinical Alzheimer's Cognitive Composite (PACC), PACC5, and Repeatable Battery for Neuropsychological Status (RBANS) to Amyloid Status in Preclinical Alzheimer's Disease -Atabecestat Phase 2b/3 EARLY Clinical Trial

BACKGROUND

Cognitive composites commonly serve as primary outcomes in Alzheimer's disease (AD) secondary prevention trials.

OBJECTIVE

To evaluate the association between amyloid (Aβ) burden level (+/-) and performance on three separate composite endpoints: Preclinical Alzheimer's Cognitive Composite (PACC), PACC+Semantic Fluency (PACC5), and Repeatable Battery for Neuropsychological Status (RBANS).

DESIGN

Screening data from the randomized, double-blind, placebo-controlled, phase 2b/3 atabecestat EARLY study in preclinical AD participants were used in this analysis.

SETTING

The EARLY study was conducted at 143 centers across 14 countries.

PARTICIPANTS

3,569 cognitively unimpaired older adults (Clinical Dementia Rating of 0; aged 60-85 years) screened for inclusion in the EARLY study with Aβ status and at least PACC or RBANS at screening were included. Participants were categorized as those with non-pathological Aβ levels (Aβ-, n=2,824) and those with pathological Aβ levels (Aβ+, n=745) based on florbetapir uptake or levels of cerebrospinal fluid Aβ1-42.

MEASUREMENTS

Analysis of Covariance models controlling for age, sex, and education were used to examine the difference in PACC, PACC5, and RBANS between Aβ groups. Nonparametric bootstrap was used to compare sensitivity of composites to differentiate between Aβ status.

RESULTS

Of 3,569 participants, 2,116 were women (59%); 3,006 were Caucasian (84%); mean (SD) age was 68.98 (5.28) years. Aβ+ participants performed worse versus Aβ- participants on all cognitive composites though the magnitude of the Aβ effect was generally small. The Aβ+/- effect size for the PACC (Cohen's d=-0.15) was significantly greater than the RBANS (d=-0.097) while the PACC5 effect size (d=-0.139) was numerically larger than the RBANS. When examining subscores from the composites, memory tests (i.e., Free and Cued Selective Reminding Test, Figure Recall) and speed of processing (i.e., Digit-Symbol/Coding on the PACC/RBANS) exhibited the largest Aβ+/- effect sizes.

CONCLUSIONS

Cross-sectional relationships between Aβ and cognition among clinically unimpaired older adults are detectable on multi-domain cognitive composites but are relatively small in magnitude. The Aβ+/- group effect was statistically larger for PACC and marginally larger for PACC5 versus RBANS. However, interpretation of composite sensitivity to Aβ status cross-sectionally cannot be generalized to sensitivity to change over time.

Item-Level Investigation of Participant and Study Partner Report on the Cognitive Function Index from the A4 Study Screening Data

BACKGROUND

Greater subjective cognitive changes on the Cognitive Function Index (CFI) was previously found to be associated with elevated amyloid (Aß) status in participants screening for the A4 Study, reported by study partners and the participants themselves. While the total score on the CFI related to amyloid for both sources respectively, potential differences in the specific types of cognitive changes reported by either participants or their study partners was not investigated.

OBJECTIVES

To determine the specific types of subjective cognitive changes endorsed by participants and their study partners that are associated with amyloid status in individuals screening for an AD prevention trial.

DESIGN, SETTING, PARTICIPANTS

Four thousand four hundred and eighty-six cognitively unimpaired (CDR=0; MMSE 25-30) participants (ages 65-85) screening for the A4 Study completed florbetapir (Aß) Positron Emission Tomography (PET) imaging. Participants were classified as elevated amyloid (Aß+; n=1323) or non-elevated amyloid (Aß-; n=3163).

MEASUREMENTS

Prior to amyloid PET imaging, subjective report of changes in cognitive functioning were measured using the CFI (15 item questionnaire; Yes/Maybe/No response options) and administered separately to both participants and their study partners (i.e., a family member or friend in regular contact with the participant). The impact of demographic factors on CFI report was investigated. For each item of the CFI, the relationship between Aß and CFI response was investigated using an ordinal mixed effects model for participant and study partner report.

RESULTS

Independent of Aß status, participants were more likely to report 'Yes' or 'Maybe' compared to the study partners for nearly all CFI items. Older age (r= 0.06, p<0.001) and lower education (r=-0.08, p<0.001) of the participant were associated with higher CFI. Highest coincident odds ratios related to Aß+ for both respondents included items assessing whether 'a substantial decline in memory' had occurred in the last year (ORsp= 1.35 [95% CI 1.11, 1.63]; ORp= 1.55 [95% CI 1.34, 1.79]) and whether the participant had 'seen a doctor about memory' (ORsp= 1.56 [95% CI 1.25, 1.95]; ORp =1.71 [95% CI 1.37, 2.12]). For two items, associations were significant for only study partner report; whether the participant 'Repeats questions' (ORsp = 1.30 [95% CI 1.07, 1.57]) and has 'trouble following the news' (ORsp= 1.46[95% CI 1.12, 1.91]). One question was significant only for participant report; 'trouble driving' (ORp= 1.25 [95% CI 1.04, 1.49]).

CONCLUSIONS

Elevated Aβ is associated with greater reporting of subjective cognitive changes as measured by the CFI in this cognitively unimpaired population. While participants were more likely than study partners to endorse change on most CFI items, unique CFI items were associated with elevated Aß for participants and their study partners, supporting the value of both sources of information in clinical trials.

The Trial-Ready Cohort for Preclinical/Prodromal Alzheimer's Disease (TRC-PAD) Project: An Overview

The Trial-Ready Cohort for Preclinical/prodromal Alzheimer’s Disease (TRC-PAD) project is a collaborative effort to establish an efficient mechanism for recruiting participants into very early stage Alzheimer’s disease trials. Clinically normal and mildly symptomatic individuals are followed longitudinally in a web-based component called the Alzheimer’s Prevention Trial Webstudy (APT Webstudy), with quarterly assessment of cognition and subjective concerns. The Webstudy data is used to predict the likelihood of brain amyloid elevation; individuals at relatively high risk are invited for in-person assessment in the TRC screeing phase, during which a cognitive battery is administered and Apolipoprotein E genotype is obtained followed by reassessment of risk of amyloid elevation. After an initial validation study, plasma amyloid peptide ratios will be included in this risk assessment. Based on this second risk calculation, individuals may have amyloid testing by PET scan or lumbar puncture, with those potentially eligible for trials followed in the TRC, while the rest are invited to remain in the APT Webstudy. To date, over 30,000 individuals have participated in the Webstudy; enrollment in the TRC is in its early stage.

Intranasal Insulin Reduces White Matter Hyperintensity Progression in Association with Improvements in Cognition and CSF Biomarker Profiles in Mild Cognitive Impairment and Alzheimer's Disease

BACKGROUND

Intranasally administered insulin has shown promise in both rodent and human studies in Alzheimer's disease; however, both effects and mechanisms require elucidation.

OBJECTIVE

We assessed the effects of intranasally administered insulin on white matter health and its association with cognition and cerebral spinal fluid biomarker profiles in adults with mild cognitive impairment or Alzheimer's disease in secondary analyses from a prior phase 2 clinical trial (NCT01767909).

DESIGN

A randomized (1:1) double-blind clinical trial.

SETTING

Twelve sites across the United States.

PARTICIPANTS

Adults with mild cognitive impairment or Alzheimer's disease.

INTERVENTION

Participants received either twice daily placebo or insulin (20 IU Humulin R U-100 b.i.d.) intranasally for 12 months. Seventy-eight participants were screened, of whom 49 (32 men) were enrolled.

MEASUREMENTS

Changes from baseline in global and regional white matter hyperintensity volume and gray matter volume were analyzed and related to changes in cerebral spinal fluid biomarkers, Alzheimer's Disease Assessment Scale-Cognition, Clinical Disease Rating-Sum of Boxes, Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale, and a memory composite.

RESULTS

The insulin-treated group demonstrated significantly reduced changes in white matter hyperintensity volume in deep and frontal regions after 12 months, with a similar trend for global volume. White matter hyperintensity volume progression correlated with worsened Alzheimer's disease cerebral spinal fluid biomarker profile and cognitive function; however, patterns of correlations differed by treatment group.

CONCLUSION

Intranasal insulin treatment for 12 months reduced white matter hyperintensity volume progression and supports insulin's potential as a therapeutic option for Alzheimer's disease.

The Institute on Methods and Protocols for Advancement of Clinical Trials in ADRD (IMPACT-AD): A Novel Clinical Trials Training Program

BACKGROUND

Alzheimer's Disease and Related Dementias (ADRD) clinical trials require multidisciplinary expertise in medicine, biostatistics, trial design, biomarkers, ethics, and informatics.

OBJECTIVES

To provide focused interactive training in ADRD clinical trials to a diverse cadre of investigators.

DESIGN

The Institute on Methods and Protocols for Advancement of Clinical Trials in ADRD (IMPACT-AD) is a novel multidisciplinary clinical trial training program funded by the National Institute on Aging and the Alzheimer's Association with two educational tracks. The Professionals track includes individuals who fill a broad variety of roles including clinicians, study coordinators, psychometricians, and other study professionals who wish to further their knowledge and advance their careers in ADRD trials. The Fellowship track includes current and future principal investigators and focuses on the design, conduct and analysis of ADRD clinical trials.

SETTING

The 2020 inaugural iteration of IMPACT-AD was held via Zoom.

PARTICIPANTS

Thirty-five trainees (15 Fellowship track; 20 Professionals track) were selected from 104 applications (34% acceptance rate). Most (n=25, 71%) identified as female. Fifteen (43%) were of a non-white race; six (18%) were of Hispanic ethnicity; eight (23%) indicated they were the first person in their family to attend college.

MEASUREMENTS

Participants completed daily evaluations as well as pre- and post-course assessments of learning.

RESULTS

Across topic areas, >90% of trainees evaluated their change in knowledge based on the lectures as "very much" or "somewhat increased." The mean proportion correct responses in pre- and post-course assessments increased from 55% to 75% for the Professionals track and from 54% to 78% for the Fellowship track.

CONCLUSIONS

IMPACT-AD successfully launched a new training opportunity amid a global pandemic that preliminarily achieved the goals of attracting a diverse cohort and providing meaningful training. The course is funded through 2025.

The Computerized Cognitive Composite (C3) in an Alzheimer's Disease Secondary Prevention Trial

BACKGROUND

Computerized cognitive assessments may improve Alzheimer's disease (AD) secondary prevention trial efficiency and accuracy. However, they require validation against standard outcomes and relevant biomarkers.

OBJECTIVE

To assess the feasibility and validity of the tablet-based Computerized Cognitive Composite (C3).

DESIGN

Cross-sectional analysis of cognitive screening data from the A4 study (Anti-Amyloid in Asymptomatic AD).

SETTING

Multi-center international study.

PARTICIPANTS

Clinically normal (CN) older adults (65-85; n=4486).

MEASUREMENTS

Participants underwent florbetapir-Positron Emission Tomography for Aβ+/- classification. They completed the C3 and standard paper and pencil measures included in the Preclinical Alzheimer's Cognitive Composite (PACC). The C3 combines memory measures sensitive to change over time (Cogstate Brief Battery-One Card Learning) and measures shown to be declining early in AD including pattern separation (Behavioral Pattern Separation Test- Object- Lure Discrimination Index) and associative memory (Face Name Associative Memory Exam- Face-Name Matching). C3 acceptability and completion rates were assessed using qualitative and quantitative methods. C3 performance was explored in relation to Aβ+/- groups (n=1323/3163) and PACC.

RESULTS

C3 was feasible for CN older adults to complete. Rates of incomplete or invalid administrations were extremely low, even in the bottom quartile of cognitive performers (PACC). C3 was moderately correlated with PACC (r=0.39). Aβ+ performed worse on C3 compared with Aβ- [unadjusted Cohen's d=-0.22 (95%CI: -0.31,-0.13) p<0.001] and at a magnitude comparable to the PACC [d=-0.32 (95%CI: -0.41,-0.23) p<0.001]. Better C3 performance was observed in younger, more educated, and female participants.

CONCLUSIONS

These findings provide support for both the feasibility and validity of C3 and computerized cognitive outcomes more generally in AD secondary prevention trials.

RF Sputtered MoO3 Thin Film on Si (100) for Gas Sensing Applications

Molybdenum Trioxide (MoO3) films are grown on Si(100) substrates by reactive RF magnetron sputtering in plasma containing a mixture of Argon and Oxygen, using a pure Molybdenum target. In this paper, we report the deposition of (MoO3) films on Si(100) substrates under varying gas flow (O2 + Ar gas) (20 sccm to 30 sccm with the duration of deposition~ 1hr) by RF reactive magnetron sputtering at room temperature. To get crystalline MoO3 films annealing in O2 environment at 500 °C for 4 h is done. Phase formation and orientation of the film is characterized by Glancing incidence X-ray diffraction (GIXRD). The identification of the orthorhombic MoO3 phase is investigated by XRD and Raman spectroscopy. Raman lines at 819 cm-1 and 995 cm-1 are due to the (A1g, B1g) symmetric stretching (Mo-O–Mo) bond and asymmetric stretching band (Mo=O) respectively. Surface morphology and cross-sectional image of the deposited thin films were investigated by FE-SEM image. UV-Visible reflectance and cross-sectional FE-SEM image confirm the thickness of the MoO3 films with oxygen-rich and oxygen deficient phase formation occur. Reverse leakage current density of 20 sccm 1hr sample is low (1×10-6 mA/cm2) as compared to 30 sccm 1hr sample (1×10-3 mA/cm2). The higher leakage is due to crack formation during the ex-situ annealing of MoO3 films. This MoO3 films can be used in Gas sensing and switching devices.

Authors response to D Umbricht, letter to the editor referring Futility Analyses in Alzheimer's Disease (AD) Clinical Trials: A Risky Business. The Journal of Prevention of Alzheimer's Disease, 2020

Dr. Umbricht suggests that the two examples we cite in our viewpoint (1) support rather than call into question the value of interim futility analyses in Alzheimer’s disease (AD) trials. He points out that the first example, the Phase 3 trials of aducanumab, the futility analyses did indeed indicate a trend toward a beneficial treatment effect in one of the two trials though the planned pooled futility decision led to stopping the trials. In the second case, in which a futility analysis led to a halt, full analysis of available data suggested efficacy; a subsequent study was negative.

Viewpoint: Futility Analyses in Alzheimer's Disease (AD) Clinical Trials: A Risky Business

In the standard, orderly progression of drug development trials, a moderately-sized Phase 2 trial demonstrates safety and efficacy of one or more doses of the investigational product, followed by large confirmatory Phase 3 trials of one or two doses leading to regulatory approval. The large and lengthy Phase 3 trials often include interim futility analyses using statistical methods to assess lack of benefit, so that programs “fail early” by identifying ineffective treatments early if evidence points toward lack of efficacy, in part to limit financial loss and redirect resources. For disease-modifying drug development programs in Alzheimer’s disease (AD), finding an optimal strategy is particularly challenging. A slowing of decline rather than symptomatic improvement indicates disease-modification, and primary outcomes for such trials are noisy and sometimes subjective. As a result, very large, lengthy trials are required to see efficacy signals, so Phase 2 trials may look like Phase 3 programs or Phase 3 trials may directly follow Phase 1 trials. In other words, enormous trials may be launched without sufficient evidence of preliminary efficacy of the doses studied, dramatically increasing the financial risk to sponsors. In such instances, futility analyses embedded in trials would seem to be particularly important.

The ORNATE India Project: United Kingdom-India Research Collaboration to tackle visual impairment due to diabetic retinopathy

INTRODUCTION

The ORNATE India project is funded by the UK Research and Innovation (UKRI) through the Global Challenges Research Fund. The aim is to build research capacity and capability in India and the UK to tackle global burden of diabetes-related visual impairment. As there are over 77 million people with diabetes in India, it is challenging to screen every person with diabetes annually for sight-threatening diabetic retinopathy (DR). Therefore, alternate safe approaches need to be developed so that those at-risk of visual impairment due to DR is identified promptly and treated.

METHODS

The project team utilised diverse global health strategies and research methods to co-design work packages to build research capacity and capability to ensure effective, affordable and efficient DR services are made available for the population. The strategies and methods employed included health system strengthening; implementation science; establishing care pathways; co-designing collaborative studies on affordable technologies, developing quality standards and guidelines to decrease variations in care; economic analysis; risk modelling and stratification. Five integrated work packages have been developed to deal with all aspects of DR care. These included implementation of a DR screening programme in the public health system in a district in Kerala, evaluating regional prevalence of diabetes and DR and assessing ideal tests for holistic screening for diabetes and its complications in 20 areas in India, utilising artificial intelligence on retinal images to facilitate DR screening, exploring biomarker and biosensor research to detect people at risk of diabetes complications, estimating cost of blindness in India and risk modelling to develop risk-based screening models for diabetes and its complications. A large collaborative network will be formed to propagate research, promote shared learning and bilateral exchanges between high- and middle-income countries to tackle diabetes-related blindness.

Non-Amyloid Approaches to Disease Modification for Alzheimer's Disease: An EU/US CTAD Task Force Report

While amyloid-targeting therapies continue to predominate in the Alzheimer’s disease (AD) drug development pipeline, there is increasing recognition that to effectively treat the disease it may be necessary to target other mechanisms and pathways as well. In December 2019, The EU/US CTAD Task Force discussed these alternative approaches to disease modification in AD, focusing on tau-targeting therapies, neurotrophin receptor modulation, anti-microbial strategies, and the innate immune response; as well as vascular approaches, aging, and non-pharmacological approaches such as lifestyle intervention strategies, photobiomodulation and neurostimulation. The Task Force proposed a general strategy to accelerate the development of alternative treatment approaches, which would include increased partnerships and collaborations, improved trial designs, and further exploration of combination therapy strategies.

It Is the Time to Think About a Treat-to-Target Strategy for Knee Osteoarthritis

Osteoarthritis (OA) is a rheumatic disease that affects the well-being of the patient, compromises physical and mental function, and affects other quality of life aspects. In the literature, several evidence-based guidelines and recommendations for the management of knee osteoarthritis (KOA) are available. These recommendations list the different therapeutic options rather than addressing a hierarchy between the treatments and defining the real target. Therefore, a question arises: are patients and physicians satisfied with the current management of KOA? Actually, the answer may be negative, thus suggesting a change in our therapeutic strategies. In this article, we address this challenge by suggesting that it is time to develop a “treat to target strategy” for KOA.

The Trial-Ready Cohort for Preclinical and Prodromal Alzheimer's Disease (TRC-PAD): Experience from the First 3 Years

BACKGROUND:

The Trial-Ready Cohort for Preclinical and Prodromal Alzheimer’s disease (TRC-PAD) aims to accelerate enrollment for Alzheimer’s disease (AD) clinical trials by remotely identifying and tracking individuals who are at high risk for developing symptoms of AD, and referring these individuals to in-person cognitive and biomarker evaluation with the purpose of engaging them in clinical trials. A risk algorithm using statistical modeling to predict brain amyloidosis will be refined as TRC-PAD advances with a maturing data set.

OBJECTIVES:

To provide a summary of the steps taken to build this Trial-Ready cohort (TRC) and share results of the first 3 years of enrollment into the program.

DESIGN:

Participants are remotely enrolled in the Alzheimer Prevention Trials (APT) Webstudy with quarterly assessments, and through an algorithm identified as potentially at high risk, referred to clinical sites for biomarker confirmation, and enrolled into the TRC.

SETTING:

Both an online study and in-clinic non-interventional cohort study.

PARTICIPANTS:

APT Webstudy participants are aged 50 or older, with an interest in participation in AD therapeutic trials. TRC participants must have a study partner, stable medical condition, and elevated brain amyloid, as measured by amyloid positron emission tomography or cerebrospinal fluid analysis. Additional risk assessments include apolipoprotein E genotyping.

MEASUREMENTS:

In the APT Webstudy, participants complete the Cognitive Function Index and Cogstate Brief Battery. The TRC includes the Preclinical Alzheimer’s Cognitive Composite, comprised of the Free and Cued Selective Reminding Test, the Delayed Paragraph Recall score on the Logical Memory IIa test from the Wechsler Memory Scale, the Digit-Symbol Substitution test from the Wechsler Adult Intelligence Scale-Revised, and the Mini Mental State Examination total score (1).

RESULTS:

During the first 3 years of this program, the APT Webstudy has 30,650 consented participants, with 23 sites approved for in person screening, 112 participants have been referred for in-clinic screening visits with eighteen enrolled to the TRC. The majority of participants consented to APT Webstudy have a family history of AD (62%), identify as Caucasian (92.5%), have over twelve years of formal education (85%), and are women (73%). Follow up rates for the first quarterly assessment were 38.2% with 29.5% completing the follow up Cogstate Battery.

CONCLUSIONS:

After successfully designing and implementing this program, the study team’s priority is to improve diversity of participants both in the APT Webstudy and TRC, to continue enrollment into the TRC to our target of 2,000, and to improve longitudinal retention, while beginning the process of referring TRC participants into clinical trials.

Predicting Amyloid Burden to Accelerate Recruitment of Secondary Prevention Clinical Trials

BACKGROUND:

Screening to identify individuals with elevated brain amyloid (Aβ+) for clinical trials in Preclinical Alzheimer’s Disease (PAD), such as the Anti-Amyloid Treatment in Asymptomatic Alzheimer’s disease (A4) trial, is slow and costly. The Trial-Ready Cohort in Preclinical/Prodromal Alzheimer’s Disease (TRC-PAD) aims to accelerate and reduce costs of AD trial recruitment by maintaining a web-based registry of potential trial participants, and using predictive algorithms to assess their likelihood of suitability for PAD trials.

OBJECTIVES:

Here we describe how algorithms used to predict amyloid burden within TRC-PAD project were derived using screening data from the A4 trial.

DESIGN:

We apply machine learning techniques to predict amyloid positivity. Demographic variables, APOE genotype, and measures of cognition and function are considered as predictors. Model data were derived from the A4 trial.

SETTING:

TRC-PAD data are collected from web-based and in-person assessments and are used to predict the risk of elevated amyloid and assess eligibility for AD trials.

PARTICIPANTS:

Pre-randomization, cross-sectional data from the ongoing A4 trial are used to develop statistical models.

MEASUREMENTS:

Models use a range of cognitive tests and subjective memory assessments, along with demographic variables. Amyloid positivity in A4 was confirmed using positron emission tomography (PET).

RESULTS:

The A4 trial screened N=4,486 participants, of which N=1323 (29%) were classified as Aβ+ (SUVR ≥ 1.15). The Area under the Receiver Operating Characteristic curves for these models ranged from 0.60 (95% CI 0.56 to 0.64) for a web-based battery without APOE to 0.74 (95% CI 0.70 to 0.78) for an in-person battery. The number needed to screen to identify an Aβ+ individual is reduced from 3.39 in A4 to 2.62 in the remote setting without APOE, and 1.61 in the remote setting with APOE.

CONCLUSIONS:

Predictive algorithms in a web-based registry can improve the efficiency of screening in future secondary prevention trials. APOE status contributes most to predictive accuracy with cross-sectional data. Blood-based assays of amyloid will likely improve the prediction of amyloid PET positivity.

TRC-PAD: Accelerating Recruitment of AD Clinical Trials through Innovative Information Technology

BACKGROUND

The Trial-Ready Cohort for Preclinical/Prodromal Alzheimer's Disease (TRC-PAD) Informatics Platform (TRC-PAD IP) was developed to facilitate the efficient selection, recruitment, and assessment of study participants in support of the TRC-PAD program.

OBJECTIVES

Describe the innovative architecture, workflows, and components of the TRC-PAD IP.

DESIGN

The TRC-PAD IP was conceived as a secure, scalable, multi-tiered information management platform designed to facilitate high-throughput, cost-effective selection, recruitment, and assessment of TRC-PAD study participants and to develop a learning algorithm to select amyloid-bearing participants to participate in trials of early-stage Alzheimer's disease.

SETTING

TRC-PAD participants were evaluated using both web-based and in-person assessments to predict their risk of amyloid biomarker abnormalities and eligibility for preclinical and prodromal clinical trials. Participant data were integrated across multiple stages to inform the prediction of amyloid biomarker elevation.

PARTICIPANTS

TRC-PAD participants were age 50 and above, with an interest in participating in Alzheimer's research.

MEASUREMENTS

TRC-PAD participants' cognitive performance and subjective memory concerns were remotely assessed on a longitudinal basis to predict participant risk of biomarker abnormalities. Those participants determined to be at the highest risk were invited to an in-clinic screening visit for a full battery of clinical and cognitive assessments and amyloid biomarker confirmation using positron emission tomography (PET) or lumbar puncture (LP).

RESULTS

The TRC-PAD IP supported growth in recruitment, screening, and enrollment of TRC-PAD participants by leveraging a secure, scalable, cost-effective cloud-based information technology architecture.

CONCLUSIONS

The TRC-PAD program and its underlying information management infrastructure, TRC-PAD IP, have demonstrated feasibility concerning the program aims. The flexible and modular design of the TRC-PAD IP will accommodate the introduction of emerging diagnostic technologies.

EU/US/CTAD Task Force: Lessons Learned from Recent and Current Alzheimer's Prevention Trials

At a meeting of the EU/US/Clinical Trials in Alzheimer's Disease (CTAD) Task Force in December 2016, an international group of investigators from industry, academia, and regulatory agencies reviewed lessons learned from ongoing and planned prevention trials, which will help guide future clinical trials of AD treatments, particularly in the pre-clinical space. The Task Force discussed challenges that need to be addressed across all aspects of clinical trials, calling for innovation in recruitment and retention, infrastructure development, and the selection of outcome measures. While cognitive change provides a marker of disease progression across the disease continuum, there remains a need to identify the optimal assessment tools that provide clinically meaningful endpoints. Patient- and informant-reported assessments of cognition and function may be useful but present additional challenges. Imaging and other biomarkers are also essential to maximize the efficiency of and the information learned from clinical trials.

A novel and less invasive technique to assess cytokine profile of vitreous in patients of diabetic macular oedema

PurposeA pilot study to validate the collection of vitreous reflux (VR) after intravitreal injection using Schirmers tear strips was carried out. We assessed its efficiency for proteomics studies by estimating the differential expression of 27 cytokines using multiplexed bead array in diabetic macular oedema and proliferative diabetic retinopathy. To set, validate and assess the efficacy of Schirmer tear strips for collecting VR in patients undergoing intravitreal injections for diabetic macular oedema (DME).Patients and methodsVR samples were collected from 11 eyes of DME patients after intravitreal injections using Schirmer tear strips. Undiluted vitrectomy samples were obtained from six eyes of non-diabetic patients with idiopathic macular hole and seven eyes of diabetic patients with high-risk proliferative diabetic retinopathy (Hr-PDR), which were also subsampled on the Schirmer tear strips. Tear sampling was done in a subset of the DME patients. Total protein concentration between VR and vitrectomy samples was compared. Levels of the set of 27 cytokines in Schirmer tear strips samples were measured. Inter-group comparison for cytokines was done using Mann-Whitney U-test.ResultsSimilar protein concentration in VR samples and vitrectomy samples (P<0.05) was obtained. Tear protein contamination was not detected in VR samples. In comparison with no-DR patients, 25 and 20 of the measured 27 cytokines were significantly elevated (P<0.05) in the Hr-PDR and DME patients, respectively. As compared with no-DR patients, vascular endothelial growth factor was only moderately elevated in DME patients (P>0.05), but significantly elevated in Hr-PDR patients (P<0.05). Interleukin 1 receptor antagonist/interleukin 1b (IL1RA/IL1b) ratio was 13 times higher in DME patients as compared with Hr-PDR group.ConclusionWe demonstrated a simple, safe method of VR sampling. This technique provides a pure, albeit small, vitreous sample for proteomics. IL1RA/IL1b ratio was found to be 13-fold higher in the DME group as compared to the Hr-PDR.

Defining the Optimal Target Population for Trials of Polyunsaturated Fatty Acid Supplementation Using the Erythrocyte Omega-3 Index: A Step Towards Personalized Prevention of Cognitive Decline?

OBJECTIVES

to identify the optimal erythrocyte omega-3 index cut-off for predicting cognitive decline and/or polyunsaturated fatty acid (PUFA) treatment response, in order to better define the target population for future dementia prevention trials.

DESIGN AND SETTING

Secondary exploratory analysis of the randomized controlled MAPT prevention trial.

PARTICIPANTS

724 dementia-free subjects aged 70 or older with subjective memory complaints, limitations in one instrumental activity of daily living, and/or slow gait speed.

INTERVENTION

800mg docosahexaenoic acid (DHA) and 225mg eicosapentaenoic acid (EPA) daily versus placebo.

MEASUREMENTS

Erythrocyte omega-3 index was measured at baseline. Cognition was measured over 3 years with a composite cognitive score (mean of 4 z-scores).

RESULTS

Placebo group subjects in the lowest quartile of baseline erythrocyte omega-3 index (i.e. ≤4.83%) underwent significantly more 3-year cognitive decline than the other quartiles (mean composite score difference 0.14, 95%CI [0.00, 0.28], p=0.048). In a ROC curve analysis, the optimal omega-3 index cut-off for predicting notable cognitive decline was 5.3%. There was a consistent but non-significant difference in 3-year cognitive decline of approximately 0.12 points between PUFA-treated and placebo subjects with "low" baseline omega-3 index when the cut-off was set at ≤5.27%.

CONCLUSIONS

Dementia-free older adults with an omega-3 index below approximately 5% are at increased risk of cognitive decline, and could be a good target population for testing the cognitive effects of PUFA supplementation.

The prevalence and fate of the defunctioning stoma in patients with anal cancer: a regional experience following the ACT II trial

AIM

UK guidance advises the creation of a defunctioning stoma for anal tumours infiltrating the vagina, impending obstruction or significant faecal incontinence. Other patients may be offered a defunctioning stoma at the discretion of the clinician. The purpose of this study was to establish the prevalence and fate of defunctioning stomas in a regional anal cancer service, with reference to the results from the recent ACT II trial.

METHOD

Oncological treatment was standardized as described in the ACT II trial. All patients from 2010 to 2013 inclusive were included. Collected data were correlated with both the IMRT guidelines and the outcomes of the ACT II trial. Kaplan-Meier survival analysis was applied to stoma-free survival to the end of the study period.

RESULTS

Seventy-six patients were identified during the study period, of whom 51% had a defunctioning stoma. Twenty were performed for anterior tumours without infiltration into the vagina (Group A), whilst 19 had a stoma for indications as set out by the guidelines (Group B). Stoma reversal was performed in 41% of patients, 13/20 in Group A and 3/19 in Group B. The median time to reversal was 11 months. Eleven deaths were recorded and six patients still had their stomas at time of death. Stoma-free survival was 74%. No new ano-vaginal fistulation occurred as a consequence of treatment.

CONCLUSION

The tumour features that are indications for defunctioning as advised by the UK IMRT guidelines are associated with a poorer overall outcome, and these stomas are less likely to be reversed. The majority of stomas, however, were formed for anterior tumours without infiltration into the vagina and were more likely to be successfully reversed.

Dissecting the Biological Heterogeneity within Hormone Receptor Positive HER2 Negative Breast Cancer by Gene Expression Markers Identifies Indolent Tumors within Late Stage Disease

Hormone receptor positive (HR+) breast cancers are a heterogeneous class with differential prognosis. Although more than half of Indian women present with advanced disease, many such patients do well. We have attempted identification of biologically indolent tumors within HR+HER2- tumors based on gene expression using histological grade as a guide to tumor aggression. 144 HR+HER2- tumors were divided into subclasses based on scores derived by using transcript levels of multiple genes representing survival, proliferation, and apoptotic pathways and compared to classification by Ki-67 labeling index (LI). Clinical characters and disease free survival were compared between the subclasses. The findings were independently validated in the METABRIC data set. Using the previously established estrogen receptor (ER) down stream activity equation, 20% of the tumors with greater than 10% HR positivity by immunohistochemistry (IHC) were still found to have inadequate ER function. A tumor aggression probability score was used to segregate the remainder of tumors into indolent (22%) and aggressive (58%) classes. Significant difference in disease specific survival was seen between the groups (P = .02). Aggression probability based subclassification had a higher hazard ratio and also independent prognostic value (P < .05). Independent validation of the gene panel in the METABRIC data set showed all 3 classes; indolent (24%), aggressive (68%), and insufficient ER signaling (7%) with differential survival (P = .01). In agreement with other recent reports, biologically indolent tumors can be identified with small sets of gene panels and these tumors exist in a population with predominantly late stage disease.

Particle damage sources for fused silica optics and their mitigation on high energy laser systems

High energy laser systems are ultimately limited by laser-induced damage to their critical components. This is especially true of damage to critical fused silica optics, which grows rapidly upon exposure to additional laser pulses. Much progress has been made in eliminating damage precursors in as-processed fused silica optics (the advanced mitigation process, AMP3), and very high damage resistance has been demonstrated in laboratory studies. However, the full potential of these improvements has not yet been realized in actual laser systems. In this work, we explore the importance of additional damage sources-in particular, particle contamination-for fused silica optics fielded in a high-performance laser environment, the National Ignition Facility (NIF) laser system. We demonstrate that the most dangerous sources of particle contamination in a system-level environment are laser-driven particle sources. In the specific case of the NIF laser, we have identified the two important particle sources which account for nearly all the damage observed on AMP3 optics during full laser operation and present mitigations for these particle sources. Finally, with the elimination of these laser-driven particle sources, we demonstrate essentially damage free operation of AMP3 fused silica for ten large optics (a total of 12,000 cm² of beam area) for shots from 8.6 J/cm² to 9.5 J/cm² of 351 nm light (3 ns Gaussian pulse shapes). Potentially many other pulsed high energy laser systems have similar particle sources, and given the insight provided by this study, their identification and elimination should be possible. The mitigations demonstrated here are currently being employed for all large UV silica optics on the National Ignition Facility.

Abstract P6-09-24: Vitamin D level impacts odds of pathologic complete response following neoadjuvant therapy in operable breast cancer

Introduction:

Pathologic complete response (pCR) following neoadjuvant systemic chemotherapy (NAC) serves as a measure of tumor responsiveness and is a recognized surrogate for improved long-term outcomes. Some, but not all, studies have found a positive association between vitamin D (VD) and disease-free survival. We investigated if VD at diagnosis or during chemotherapy impacts pCR following neoadjuvant chemotherapy for operable breast cancer.

Methods:

Patients from Iowa were eligible if they were enrolled in one of two Iowa registries and had serum from before or during NAC tested for VD. French patients enrolled in a previous study of the impact of NAC on vitamin D and bone metabolism were considered for this study. VD deficiency was defined as &lt;20 ng/ml. pCR was defined as no residual invasive disease in breast and lymph nodes. Firth-penalized logistic regression multivariable model was used.

Results:

The final cohort included 144 women. 84.7% of VD levels were obtained before initiation of chemotherapy. There was no difference between the French and Iowa cohorts with regard to age (p=0.20), clinical stage (p=0.22), disease receptor status (HER2+ [Hormone receptor (HR)+ or HR-], HR+/HER2-, and Triple Negative) (p=0.32) and rate of pCR (p=0.34). French women had lower body mass index (mean 24.8 vs 28.8, p&lt;0.01), lower VD levels (mean 21.5 vs 27.5, p&lt;0.01) and underwent lumpectomy instead of mastectomy more frequently (75.3% vs 47.8%, p&lt;0.01) than Iowa women. Only pCR differed between the VD sufficient and deficient groups (Table 1). In multivariate analysis, after adjusting for the effects of cohort, clinical stage, and disease type by receptor status, VD deficiency put a woman at 2.68 times increased odds of not attaining a pCR (95%CI: 1.12-6.41, p=0.03) (Table 2). This variable remained significant with VD deficiency defined as &lt;30 ng/ml and when considering this variable continuously.

Conclusion:

In this retrospective cohort, VD level before or during NAC was associated with pCR. Prospective trials could elucidate if maintaining VD levels during NAC, a highly modifiable variable, can be utilized to improve cancer outcomes in addition to benefiting other established health outcomes.

Table 1: VD Deficient and Sufficient Groups  Vitamin D (ng/ml)   Deficient (&lt; 20)Sufficient (≥ 20)pN 5391 BMIUnderweight-Normal27 (50.9)47 (51.6)0.93 Overweight-Obese26 (49.1)44 (48.4) VD LevelBefore Chemotherapy45 (84.9)77 (84.6)0.96 During Chemotherapy8 (15.1)14 (15.4) GradeG1-224 (47.1)41 (46.1)0.91 G327 (52.9)48 (53.9) Clinical StageI-II37 (69.8)61 (67)0.73 III16 (30.2)30 (33) Receptor StatusHER2+ (HR+ or HR-)12 (22.6)29 (32.2)0.20 HR+/HER2-30 (56.6)37 (41.1)  Triple Negative11 (20.8)24 (26.7) SurgeryBreast Conserving32 (60.4)58 (63.7)0.69 Mastectomy21 (39.6)33 (36.3) pCRNo43 (81.1)53 (58.2)&lt;.01 Yes10 (18.9)38 (41.8) AgeMean (SD)48 (10.9)51 (10.3)0.15

Table 2: Odds of Not Attaining a pCR: Multivariable Results  NOdds Ratio95% CIp-valueCohortIowa661.170.522.630.71 France77Ref   Vitamin D (&lt;20)Deficient532.681.126.410.03 Sufficient90Ref   Clinical StageI-II97Ref    III463.251.308.110.01Receptor StatusHER2+ (HR+ or HR-)411.060.402.810.91 HR+/HER2-675.502.0414.85&lt;0.01 Triple Negative35Ref   

Citation Format: Thomas A, Thezenas S, Mott SL, Raman R, Viala M, Pouderoux S, Schroeder MC, Lamy P-J, Jacot W. Vitamin D level impacts odds of pathologic complete response following neoadjuvant therapy in operable breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-24.

The STRokE DOC Trial Technique: ‘Video Clip, Drip, and/or Ship’

Rationale

To describe the clinical trial methods of a site-independent telemedicine system used in stroke.

Aims

A lack of readily available stroke expertise may partly explain the low rate of rt-PA use in acute stroke. Although telemedicine systems can reliably augment expertise available to rural settings, and may increase rt-PA use, point-to-point systems do require fixed base stations. Site-independent systems may minimize delay. The STRokE DOC trial assesses whether site-independent telemedicine effectively and efficiently brings rt-PA to a remote population.

Design

STRokE DOC is a 5–year, 400–participant, noninvasive trial, comparing two consultative techniques at four remote sites. Participants are randomized to acute ‘STRokE DOC telemedicine’ or ‘telephone’ consultations. Treatment decision accuracy is adjudicated at two time points, using three levels of data availability and an independent auditor.

Study outcomes

The primary outcome measure is whether there was a ‘correct decision to treat or not to treat using rt-PA’ at each of three adjudication levels (primarily at Level #2). Secondary outcomes include the number of thrombolytic recommendations, intracerebral hemorrhage, and 90–day outcomes. Using the STRokE DOC system (or telephone evaluation), medical history, neurologic scales, CT interpretations, and recommendations have been completed on over 200 participants to date. Of the initial 11, nonrandomized, ‘run-in’ patients, six (65%) were evaluated wirelessly, and five (45%) were evaluated with a site-independent LAN or cable modem. Three (27%) received rt-PA. The adjudication methodology was able to show both agreements and disagreements in these 11 cases. It is feasible to perform site-independent stroke consultations, and adjudicate those cases, using the STRokE DOC system and trial design. Telemedicine efficacy remains to be proven.

House Dust Mites in Human ear

A study was carried out to investigate the presence of mites in human ear in 58 patients (113 ears). Ear scrapings were examined under the microscope by a parasitologist for the presence of house dust mites. Results showed the presence of house dust mites in 8 (7.1%) ears. We can conclude that mites are normal commensals of the external ears in tropical countries.

Genome-wide association analyses reveal complex genetic architecture underlying natural variation for flowering time in canola

Optimum flowering time is the key to maximize canola production in order to meet global demand of vegetable oil, biodiesel and canola-meal. We reveal extensive variation in flowering time across diverse genotypes of canola under field, glasshouse and controlled environmental conditions. We conduct a genome-wide association study and identify 69 single nucleotide polymorphism (SNP) markers associated with flowering time, which are repeatedly detected across experiments. Several associated SNPs occur in clusters across the canola genome; seven of them were detected within 20 Kb regions of a priori candidate genes; FLOWERING LOCUS T, FRUITFUL, FLOWERING LOCUS C, CONSTANS, FRIGIDA, PHYTOCHROME B and an additional five SNPs were localized within 14 Kb of a previously identified quantitative trait loci for flowering time. Expression analyses showed that among FLC paralogs, BnFLC.A2 accounts for ~23% of natural variation in diverse accessions. Genome-wide association analysis for FLC expression levels mapped not only BnFLC.C2 but also other loci that contribute to variation in FLC expression. In addition to revealing the complex genetic architecture of flowering time variation, we demonstrate that the identified SNPs can be modelled to predict flowering time in diverse canola germplasm accurately and hence are suitable for genomic selection of adaptative traits in canola improvement programmes.

The prevalence and risk factors for age-related macular degeneration in rural-urban India, Sankara Nethralaya Rural-Urban Age-related Macular degeneration study, Report No. 1

PurposeTo report the age- and gender-adjusted prevalence rates of early and late age-related maculopathy (ARM) and associated risk factors in rural and urban Indian population.MethodsA population-based cross-sectional study was carried out in South India between 2009 and 2011. Of the 6617 subjects ≥60 years enumerated ones, 5495 (83.04%) participated in the eye examination. A detailed history including data on demographic, socioeconomic, and ocular history was obtained. Participants underwent detailed ophthalmic evaluation including 30° 3-field photograph as per Age-Related Eye Disease Study protocol. The ARM was graded according to the International ARM Epidemiological Study Group.ResultsAge- and gender-adjusted prevalence of early ARM was 20.91% (20.86-20.94) in the rural population and 16.37% (16.32-16.42) in the urban population. Similarly, the prevalence of late ARM was 2.26% (2.24-2.29) and 2.32% (2.29-2.34) in the rural and urban population, respectively. In both rural and urban populations, risk factors that were related to both early and late ARM were age, per year increase (OR, range 1.00-1.08); middle socioeconomic status (OR, range 1.05-1.83); and smokeless tobacco (OR, range 1.11-2.21). Protective factor in both was the presence of diabetes mellitus in all ARM (OR, range 0.34-0.83). Risk factors, only in the rural arm, were female gender (OR, range 1.06-1.64), past smoker (OR, 1.14), and serum low-density lipoprotein cholesterol level (OR, 1.03).ConclusionsThe study reports smokessless tobacco as a risk factor for both early and late ARM and identified a higher prevalence of early ARM in the rural population compared with urban population.

Abstract P1-14-14: Impact of body mass index (BMI) and neo-adjuvant chemotherapy (NAC) dosing on pathologic complete response (pCR) in operable breast cancer (bc)

Introduction:

pCR following NAC is associated with improved long term outcomes. Though obesity is associated with chemo-resistance, its impact on pCR is less clear, likely because most studies were unable to account for NAC dose adjustments. An association between taxane dose reduction and BMI has previously been shown in European populations. However, most patients (pts) with increased BMI had doses capped at BSA of 2. We studied the impact of BMI on NAC dosing when treatment is based on actual weight and whether dosing adjustments preferentially impact pCR rate.

Methods: Pts prospectively enrolled in the University of Iowa Breast Molecular Epidemiologic Resource from 2010-14 with invasive bc who received at least one cycle of NAC were eligible. Pts were stratified by BMI category: normal (BMI ≤25) or overweight-obese (BMI &gt;25). Planned total dose was calculated based on both dosing and number of cycles. Dose reduction was defined as any decrease in total intended dose. pCR was defined as no residual invasive disease in breast and lymph nodes. To investigate the relationship between BMI, dose reductions, and pCR, chi-square tests and logistic regression models were used.

Results: 87 pts were eligible. 22 (26%), 25 (29%) and 51 (59%) of pts had HER2 positive, triple negative and hormone receptor positive bc (HER- or +), respectively. 62 (71%) pts had Stage I-II bc. All pts received a combination of taxanes with other agents (Cytoxan, 5FU, Carboplatin, Gemcitabine) with or without an anthracycline (Adriamycin or Epirubicin) or anti HER 2 therapy (Pertuzumab, Traztuzumab or Lapatinib) and were initially dosed based upon actual body weight. Taxanes were planned at treatment initiation in all pts. Anthracyclines were given to 71 (82%) pts. pCR was achieved in 28 (32%) pts. Association between BMI and NAC dosing are shown in -

Table 1: Association between NAC dosing and BMI category NormalOverweight-ObesepN3651  NoYesNoYes Taxane dose reduction30(83%)6(17%)29(57%)22(43%)&lt;0.01Non taxane dose reduction28(78%)8(22%)40(78%)11(22%)0.94

. Relative to normal weight pts, overweight-obese pts were more likely not to achieve a pCR (OR 2.09, CI 0.84-5.21, p=0.11) and have residual disease in the breast alone (OR 2.92, CI 1.18-7.24, p=0.02). Overweight-obese pts with taxane reductions, relative to overweight-obese pts without taxane reductions, were at elevated odds of not achieving a pCR (OR 2.03, CI 0.53-7.73) -.

Table 2: Impact of taxance dose reduction on pCR by BMI category  NormalOverweight-Obese  No pCRpCRNo pCRpCRTaxane reductionNo19(63%)11(37%)20(69%)9(31%) Yes2(33%)4(67%)18(82%)4(28%)

Interaction between BMI and taxane dose reduction on pCR trended towards significance (p=0.10), a trend not seen for non-taxane drugs. The most common adverse event resulting in taxane dose reduction was neuropathy (10/28 pts).

Conclusion: Overweight-obese women experienced significantly higher rates of taxane dose reductions during NAC for bc with initial full-weight dosing. BMI status may modify the effects of taxane dose reduction on the likelihood of not achieving a pCR, Further investigation of this outcome in a larger cohort is warranted.

Citation Format: Raman R, Mott SL, Schroeder MC, Thomas A. Impact of body mass index (BMI) and neo-adjuvant chemotherapy (NAC) dosing on pathologic complete response (pCR) in operable breast cancer (bc). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-14.

Abstract P5-08-48: Vitamin D deficiency in various breast cancer subtypes and its impact on response to neoadjuvant chemotherapy in operable breast cancer

Introduction:

Pathologic complete response (pCR) to neoadjuvant chemotherapy (NAC) is associated with improved long-term outcomes. Vitamin D (VD) deficiency has been associated with carcinogenesis as well as poorer outcomes in breast cancer (bc) particularly in luminal-type bc. In addition, replacement of VD during adjuvant chemotherapy was found to improve disease-free survival. However, VD deficiency was not associated with pCR following NAC in one series which included patients (pts) with human epidermal growth factor receptor-2 (HER2) negative bc only. We report the relationship between VD deficiency and pCR in a cohort that includes all bc subtypes and report how VD deficiency varied by clinical and pathologic parameters.

Methods:

Patients (pts) prospectively enrolled in the University of Iowa Breast Molecular Epidemiologic Resource between 2010-14 with invasive bc, receiving at least one cycle of NAC, and who had serum collected at enrollment or during NAC were eligible. VD deficiency was defined as &lt; 20 ng/dl. pCR was defined as no residual invasive disease in breast and lymph nodes. Patients were stratified by their BMI as normal (≤ 25 kg/m2) or overweight-obese (&gt;25 kg/m2). To investigate the relationship between VD, clinical parameters, and NAC outcomes, chi-square, Fisher's exact, and t-tests were used.

Results:

73 pts were eligible. 52 (71%) pts had Stage I-II bc. All pts received a combination of taxanes with other agents (Cytoxan, 5FU, Carboplatin, Gemcitabine) with or without an anthracycline or anti-HER 2 therapy. 62/73 (85%) received an anthracycline. 65/73 (89%) received at least 75% of intended NAC. pCR was achieved in 25/73 (34%) pts. VD deficiency was found in 17/73 (23%) pts and was more frequent among overweight-obese pts (Table 1). VD deficiency occurred significantly more often in estrogen receptor (ER)+/progesterone receptor (PR)+/HER2- and ER+ or PR+ bc but not in HER2+ bc. Results suggest VD deficient pts may be at increased odds of not achieving a pCR (OR=3.02, p=0.10). In this cohort, VD deficient pts were at increased odds of having residual disease in the breast (OR=3.76, p=0.05), but not in the nodes (OR=1.43, p=0.53), (Table 2).

Conclusion:

Being overweight-obese was associated with VD deficiency and may warrant screening in this group. VD deficiency was significantly associated with ER+/PR+/HER2-bc and ER+ or PR+ disease. Notably, these pts are candidates for bone-injuring anti-estrogen agents as part of their overall course of therapy. VD deficiency was not significantly associated with pCR after NAC though a trend was suggested.

Table 1: VD and clinical parameters   VD Sufficient VD Deficientp  N=56N=17 Age (mean in years) 52470.16BMI≤2526(46%)3(18%)0.03 &gt;2530(54%)14(82%) Ellis-Ellison grade1-224(43%)7(41%)0.90 332(57%)10(59%) Tumor receptorER+/PR+/HER2-15(27%)10(59%)0.02 ER+ or PR+/HER2+6(11%)3(18%)0.43 ER-/PR-/HER2+10(18%)0(0%)0.10 ER-/PR-/HER2-17(31%)3(18%)0.36 ER+ or PR+29(52%)14(82%)0.02 HER2+16(84%)3(16%)0.53

Table 2: VD and NAC Outcomes   VD SufficientVD Deficientp  N=56N=17 pCRNo34(61%)14(82%)0.10 Yes22(39%)3(18%) Breast Residual DiseaseNo25(45%)3(18%)0.05 Yes31(55%)14(84%) Node Residual DiseaseNo28(50%)7(41%)0.52 Yes28(50%)10(59%) 

Citation Format: Raman R, Link BK, Mott SL, Schroeder MC, Thomas A. Vitamin D deficiency in various breast cancer subtypes and its impact on response to neoadjuvant chemotherapy in operable breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-48.

Role of folate-homocysteine pathway gene polymorphisms and nutritional cofactors in Down syndrome: A triad study

STUDY QUESTION

Do gene-gene and gene-environment interactions in folate-homocysteine (Hcy) pathway have a predisposing role for Down syndrome (DS)?

SUMMARY ANSWER

The study provides evidence that in addition to advanced age, maternal genotype, micronutrient deficiency and elevated Hcy levels, individually and in combination, are risk factors for Down syndrome.

WHAT IS KNOWN ALREADY

Polymorphisms in certain folate-Hcy-pathway genes (especially the T allele of MTHFR C677T), elevated Hcy and poor folate levels in mothers during pregnancy have been shown to be risk factors for Down syndrome in certain Asian populations (including the eastern region of India), while the same SNPs are not a risk factor in European populations. This conflicting situation alludes to differential gene-environment (nutrition) interactions in different populations which needs to be explored.

STUDY DESIGN, SIZE, DURATION

Between 2008 and 2012, 151 Down syndrome triads and 200 age-matched controls (Control mothers n = 186) were included in the study. Seven polymorphisms in six genes of folate-Hcy metabolic pathway, along with Hcy, cysteine (Cys), vitamin B12 (vit-B12) and folate levels, were analysed and compared among the case and control groups.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Genotyping was performed by the PCR-RFLP technique. Levels of homocysteine and cysteine were measured by HPLC while vitamin B12 and folate were estimated by chemiluminescence.

MAIN RESULTS AND THE ROLE OF CHANCE

We demonstrate that polymorphisms in the folate-Hcy pathway genes in mothers collectively constitute a genotypic risk for DS which is effectively modified by interactions among genes and by the environment affecting folate, Hcy and vitamin B12 levels. The study also supports the idea that these maternal risk factors provide an adaptive advantage during pregnancy supporting live birth of the DS child.

LIMITATIONS AND REASONS FOR CAUTION

Our inability to obtain genotype and nutritional assessments of unaffected siblings of the DS children was an important limitation of the study. Also, its confinement to a specific geographic region (the eastern part) of India, and relatively small sample size is a limitation. A parallel investigation on another population could add greater authenticity to the data.

WIDER IMPLICATIONS OF THE FINDINGS

For mothers genetically susceptible to deliver a DS child (particularly in South Asia), peri-conceptional nutritional supplementation and antenatal care could potentially reduce the risk of a DS child. Additionally, nutritional strategies could possibly be used for better management of the symptoms of DS children.

STUDY FUNDING/COMPETING INTERESTS

The work is funded through Programme support for Genetic disorders by Department of Biotechnology, Government of India to R.R. The authors declare no conflict of interest.

Plasmoids Formation During Simulations of Coaxial Helicity Injection in the National Spherical Torus Experiment

The formation of an elongated Sweet-Parker current sheet and a transition to plasmoid instability has for the first time been predicted by simulations in a large-scale toroidal fusion plasma in the absence of any preexisting instability. Plasmoid instability is demonstrated through resistive MHD simulations of transient coaxial helicity injection experiments in the National Spherical Torus Experiment (NSTX). Consistent with the theory, fundamental characteristics of the plasmoid instability, including fast reconnection rate, have been observed in these realistic simulations. Motivated by the simulations, experimental camera images have been revisited and suggest the existence of reconnecting plasmoids in NSTX. Global, system-size plasmoid formation observed here should also have strong implications for astrophysical reconnection, such as rapid eruptive solar events.