The World Rugby and International Rugby Players Contact Load Guidelines: From conception to implementation and the future

Managing training load in rugby union is crucial for optimising performance and injury prevention. Contact training warrants attention because of higher overall injury and head impact risk, yet players must develop physical, technical, and mental skills to withstand the demands of the game. To help coaches manage contact loads in professional rugby, World Rugby and International Rugby Players convened an expert working group. They conducted a global survey with players to develop contact load guidelines. This commentary aims to describe the contact load guidelines and their implementation, and identify areas where future work is needed to support their evolution.

Beyond the symptom: the biology of fatigue

A workshop titled "Beyond the Symptom: The Biology of Fatigue" was held virtually September 27-28, 2021. It was jointly organized by the Sleep Research Society and the Neurobiology of Fatigue Working Group of the NIH Blueprint Neuroscience Research Program. For access to the presentations and video recordings, see: https://neuroscienceblueprint.nih.gov/about/event/beyond-symptom-biology-fatigue. The goals of this workshop were to bring together clinicians and scientists who use a variety of research approaches to understand fatigue in multiple conditions and to identify key gaps in our understanding of the biology of fatigue. This workshop summary distills key issues discussed in this workshop and provides a list of promising directions for future research on this topic. We do not attempt to provide a comprehensive review of the state of our understanding of fatigue, nor to provide a comprehensive reprise of the many excellent presentations. Rather, our goal is to highlight key advances and to focus on questions and future approaches to answering them.

Rhythms in barriers and fluids: Circadian clock regulation in the aging neurovascular unit

The neurovascular unit is where two very distinct physiological systems meet: The central nervous system (CNS) and the blood. The permeability of the barriers separating these systems is regulated by time, including both the 24 h circadian clock and the longer processes of aging. An endogenous circadian rhythm regulates the transport of molecules across the blood-brain barrier and the circulation of the cerebrospinal fluid and the glymphatic system. These fluid dynamics change with time of day, and with age, and especially in the context of neurodegeneration. Factors may differ depending on brain region, as can be highlighted by consideration of circadian regulation of the neurovascular niche in white matter. As an example of a potential target for clinical applications, we highlight chaperone-mediated autophagy as one mechanism at the intersection of circadian dysregulation, aging and neurodegenerative disease. In this review we emphasize key areas for future research.

Keeping an eye on circadian time in clinical research and medicine

BACKGROUND

Daily rhythms are observed in humans and almost all other organisms. Most of these observed rhythms reflect both underlying endogenous circadian rhythms and evoked responses from behaviours such as sleep/wake, eating/fasting, rest/activity, posture changes and exercise. For many research and clinical purposes, it is important to understand the contribution of the endogenous circadian component to these observed rhythms.

CONTENT

The goal of this manuscript is to provide guidance on best practices in measuring metrics of endogenous circadian rhythms in humans and promote the inclusion of circadian rhythms assessments in studies of health and disease. Circadian rhythms affect all aspects of physiology. By specifying minimal experimental conditions for studies, we aim to improve the quality, reliability and interpretability of research into circadian and daily (i.e., time-of-day) rhythms and facilitate the interpretation of clinical and translational findings within the context of human circadian rhythms. We describe protocols, variables and analyses commonly used for studying human daily rhythms, including how to assess the relative contributions of the endogenous circadian system and other daily patterns in behaviours or the environment. We conclude with recommendations for protocols, variables, analyses, definitions and examples of circadian terminology.

CONCLUSION

Although circadian rhythms and daily effects on health outcomes can be challenging to distinguish in practice, this distinction may be important in many clinical settings. Identifying and targeting the appropriate underlying (patho)physiology is a medical goal. This review provides methods for identifying circadian effects to aid in the interpretation of published work and the inclusion of circadian factors in clinical research and practice.

Anastomosis Groups of Rhizoctonia solani and Binucleate Rhizoctonia Associated with Potatoes in Idaho

A survey of the relative incidence of anastomosis groups (AGs) of Rhizoctonia spp. associated with potato disease was conducted in Idaho, the leading potato producing state in the U.S.A. In total, 169 isolates of Rhizoctonia solani and seven binucleate Rhizoctonia (BNR) isolates were recovered from diseased potato plants. The AG of each isolate was determined through real-time PCR assays for AG 3-PT and phylogenetic analysis of the internal transcribed spacer region of ribosomal DNA. AG 3-PT was the predominant AG, accounting for 85% of isolates recovered, followed by AG 2-1 (5.7%) and AG 4 HG-II (4.5%). Two different subsets of AG 2-1 isolates were recovered (subset 2 and 3). Three isolates each of AG A and AG K were recovered, as well as one isolate each of AG 5 and AG W. An experiment carried out under greenhouse conditions with representative isolates of the different AGs recovered from Idaho potatoes showed differences in aggressiveness between AGs to potato stems, with AG 3-PT being the most aggressive followed by an isolate of AG 2-1 (subset 3). The three BNR isolates representative of AG A, AG K, and AG W appeared to be less aggressive to potato stems than the R. solani isolates except for the AG 2-1 (subset 2) isolate. This is the first comprehensive study of the relative incidences of Rhizoctonia species associated with Idaho potatoes and the first study to report the presence of BNR AG W outside of China.

A functional context for heterogeneity of the circadian clock in cells

Characterization of circadian systems at the organism level—a top-down approach—has led to definition of unifying properties, a hallmark of the science of chronobiology. The next challenge is to use a bottom-up approach to show how the molecular workings of the cellular circadian clock work as building blocks of those properties. We review new studies, including a recently published PLOS Biology paper by Nikhil and colleagues, that show how programmed but also stochastic generation of variation in cellular circadian period explain important adaptive features of entrained circadian phase.

A recent PLOS Biology paper shows that clonal cell populations are themselves a collection heterogeneous cellular circadian clocks; this Primer explores the implications, proposing that the phase of entrainment of biological clocks (to time of day or to season) is granular, built from the contributions of individual cells.

P361 Assessment of accuracy and reproducibility of coronary flow reserve measured by SPECT in patients with known or suspected coronary artery disease

Funding Acknowledgements

Spectrum Dynamics

Background

Traditional relative assessment of regional myocardial perfusion by single photon emission computed tomography (SPECT) has limited ability to identify multivessel coronary artery disease, as well as diffuse atherosclerosis and coronary microvascular dysfunction. Current gamma cameras with cadmium-zinc-telluride (CZT) detectors have higher temporal resolution and sensitivity and allow the acquisition of multi-frame images and quantification of absolute myocardial blood flow (MBF) and coronary flow reserve (CFR

Purpose

The aim of this study was to assess the accuracy and reproducibility of quantitative measurements of MBF and CFR obtained with a CZT SPECT system compared to PET in a cohort of patients with known or suspected coronary artery disease.

Methods

Accuracy was assessed in 22 patients who underwent dynamic rest/stress 99mTc-sestamibi-SPECT and 13N-ammonia PET myocardial perfusion imaging within two weeks of each other. Fourteen patients comprised the reproducibility cohort and underwent two dynamic 99mTc-sestamibi SPECT scans within two weeks. A rest/pharmacological stress single-day SPECT protocol was performed, using a 1:3 dose ratio. SPECT image reconstruction was performed using a spline-fitting method and SPECT MBF was quantified using a net retention kinetic model in commercially available software. Rest MBF and CFR were adjusted for heart-rate pressure product.

Results

Global MBF at rest and stress showed a good correlation between SPECT and PET (r = 0.814, p < 0.001). For global rest MBF the mean difference between the two techniques was -0.25 ± 0.24 ml/min/g, while for stress MBF mean difference was -0.21 ± 0.40 ml/min/g. We also observed a significant correlation between global SPECT and PET CFR measurements (r = 0.745, p < 0.001), with no significant difference between the two (mean difference: 0.16 ± 0.50). Regarding the reproducibility cohort, the correlation between global CFR measured by two SPECT scans was also significant (r = 0.616, p = 0.019), with a mean difference of 0.14 ±0.51. The mean difference between scans for rest MBF (-0.05 ± 0.19) and stress MBF (0.01 ± 0.42) were also not significant.

Conclusion

MBF and CFR quantification is feasible using a CZT gamma camera and provides accurate and reproducible results that correlate with 13N-ammonia PET. This may be of special relevance in sites where PET is not available, enabling MBF and CFR quantification with CZT SPECT cameras.

Abstract P361 Figure.

Optical trapping assisted detection rate enhancement of single molecules on a nanopore optofluidic chip

We use optical trapping to deliver molecular targets to the vicinity of a nanopore for high-throughput single molecule analysis on an optofluidic chip. DNA detection rates increase over 80× to enable detection at attomolar concentrations.

C-09 Diastolic Blood Pressure and Executive Function in Healthy Older Adults

Objective

Our aim was to investigate the effect of elevated diastolic blood pressure (DBP) within normal blood pressure range (NBPR) on an executive functioning task (Stroop C) in a cognitively healthy, high functioning, older adult population.

Method

Archival data at Huntington Medical Research Institutes provided 35 cognitively healthy, high functioning adults from 63 to 89 years of age (M = 76, SD = 7.0). The majority were female and Caucasian, and had college or higher degrees. A general linear model (GLM) regression analysis was performed to determine if the Stroop C Interference z score would be predicted by DBP NBPR when controlling for age, sex, education level, and ApoE4 genotype.

Results

The regression model for DBP NBPR on Stroop Interference z scores was significant, F(5, 29) = 1.56, p < .05, with increased DBP NBPR associated with decreased Stroop Interference z scores (slower completion time).

Conclusions

Increased DBP NBPR was negatively associated with executive functioning as indicated by Stroop C Interference performance, such that individuals with slower completion times had elevated DBP NBPR measurements. These results suggest that increased DBP NBPR may play a role in the reduction of executive functioning performance in cognitively healthy older adults and are consistent with prior findings identifying increased DBP as a risk factor for neurodegeneration (den Heijer et al., 2005; Kennelly et al., 2009). The current study highlights the need for increased attention to the role of DBP in neurodegeneration.

C-08 Hippocampal Volume in a Cognitively Healthy Population Scoring Within Normal Limits on Cognitive Tasks

Objective

Our aim was to investigate hippocampal volume in a cognitively healthy aging population that scored within normal limits on neuropsychological testing. Decreased hippocampal volume was expected to predict decreased memory performance, and not expected to predict executive function.

Method

A cross-sectional design was conducted from archival data at Huntington Medical Research Institutes. The sample consisted of 35 older adults (63-89 years) with college degrees or higher. Hippocampal volume and intracranial volume were obtained via MRI, and neuropsychological assessment measures included Wechsler Memory Scale, 3rd edition (WMS-III), California Verbal Learning Test, 2nd edition (CVLT-II), and the Stroop Color and Word Test.

Results

Total hippocampal volume was a good predictor of Logical Memory delayed (LM-II) scores (Figure 1), such that a larger hippocampus was associated with poorer LM-II performance (p < .01). Consistent with the above, both left hemisphere (LH) (p = .03), and right hemisphere (RH) hippocampal volume (p < .01), were found to be good predictors of LM-II scores, and a larger RH or LH hippocampus was associated with poorer performance. Neither CVLT-II nor Stroop C Interference sores were significantly related to total hippocampal volume.

Conclusion(s)

Unexpectedly, participants with a larger hippocampus performed more poorly on the LM-II task. These results might be explained by the effects of neuroinflammation in early Alzheimer’s disease pathology. However, given that the MRI volumes did not account for atrophy or damaged cortical tissue, inference is limited. Future research investigating the early pathology of brain aging in the hippocampus in cognitively healthy individuals is recommended.

On demand delivery and analysis of single molecules on a programmable nanopore-optofluidic device

Nanopore-based single nanoparticle detection has recently emerged as a vibrant research field with numerous high-impact applications. Here, we introduce a programmable optofluidic chip for nanopore-based particle analysis: feedback-controlled selective delivery of a desired number of biomolecules and integration of optical detection techniques on nanopore-selected particles. We demonstrate the feedback-controlled introduction of individual biomolecules, including 70S ribosomes, DNAs and proteins into a fluidic channel where the voltage across the nanopore is turned off after a user-defined number of single molecular insertions. Delivery rates of hundreds/min with programmable off-times of the pore are demonstrated using individual 70S ribosomes. We then use real-time analysis of the translocation signal for selective voltage gating of specific particles from a mixture, enabling selection of DNAs from a DNA-ribosome mixture. Furthermore, we report optical detection of nanopore-selected DNA molecules. These capabilities point the way towards a powerful research tool for high-throughput single-molecule analysis on a chip.

Note: Eliminating stripe artifacts in light-sheet fluorescence imaging

We report two techniques to mitigate stripe artifacts in light-sheet fluorescence imaging. The first uses an image processing algorithm called the multidirectional stripe remover method to filter stripes from an existing image. The second uses an elliptical holographic diffuser with strong scattering anisotropy to prevent stripe formation during image acquisition. These techniques facilitate accurate interpretation of image data, especially in denser samples. They are also facile and cost-effective.

Estimating Direct Cost of Cystic Fibrosis Care Using Irish Registry Healthcare Resource Utilisation Data, 2008-2012

BACKGROUND

Understanding the determinants of cost of cystic fibrosis (CF) care and health outcomes may be useful for financial planning for the delivery of CF services. Registries contain information otherwise unavailable to healthcare activity/cost monitoring systems. We estimated the direct medical cost of CF care using registry data and examined how cost was affected by patient characteristics and CF gene (CF Transmembrane Conductance Regulator [CFTR]) mutation.

METHODS

Healthcare resource utilisation data (2008-2012) were obtained for CF patients enrolled with the Irish CF Registry by 2013 from linked registry and national hospitalisation database records. Mean annual hospitalisation and medication per-patient costs were estimated by demographic profile, CFTR mutation, clinical status, and CF co-morbidity, and were presented in 2014 euro values. A mixed-effects regression model was used to examine the effect of demographic, CFTR mutation, and clinical outcomes on the log₁₀ cost of direct medical CF care.

RESULTS

Using 4261 observations from 1100 patients, we found that the median annual total cost per patient increased over the period 2008-2012 from €12,659 to €16,852, inpatient bed-day cost increased from €14,026 to €17,332, and medication cost increased from €5863 to €12,467. Homozygous F508-CFTR mutation (class II) cost was highest and milder mutation (class IV/V) cost was 49% lower. Baseline estimated cost in 2008 for a hypothetical underweight, homozygous F508del-CFTR 6-year-old female without chronic Pseudomonas aeruginosa/Staphylococcus aureus, CF-related diabetes (CFRD) or methicillin-resistant S. aureus (MRSA), and with a poor percent predicted forced expiratory volume in 1 s (ppFEV₁) was €10,113, and was €21,082 in a 25-year-old with the same hypothetical profile. Chronic P. aeruginosa infection increased baseline cost by 39%, CF co-morbidity diabetes by 18%, and frequency of pulmonary exacerbation by 15%. Underweight, declining ppFEV₁, chronic S. aureus colonisation, and time also influenced cost.

CONCLUSIONS

CFTR mutation is an important factor influencing the cost of CF care. Costs differ among cohorts of CF patients eligible to access new and emerging CFTR repair therapies. These findings support the evaluation of outcome-associated cost in CFTR mutation-specific CF patient groups.

Drug-resistant tuberculosis clinical trials: proposed core research definitions in adults

Drug-resistant tuberculosis (DR-TB) is a growing public health problem, and for the first time in decades, new drugs for the treatment of this disease have been developed. These new drugs have prompted strengthened efforts in DR-TB clinical trials research, and there are now multiple ongoing and planned DR-TB clinical trials. To facilitate comparability and maximise policy impact, a common set of core research definitions is needed, and this paper presents a core set of efficacy and safety definitions as well as other important considerations in DR-TB clinical trials work. To elaborate these definitions, a search of clinical trials registries, published manuscripts and conference proceedings was undertaken to identify groups conducting trials of new regimens for the treatment of DR-TB. Individuals from these groups developed the core set of definitions presented here. Further work is needed to validate and assess the utility of these definitions but they represent an important first step to ensure there is comparability in clinical trials on multidrug-resistant TB.

Setting targets leads to greater long-term weight losses and 'unrealistic' targets increase the effect in a large community-based commercial weight management group

Background

Setting personal targets is an important behavioural component in weight management programmes. Normal practice is to encourage ‘realistic’ weight loss, although the underlying evidence base for this is limited and controversial. The present study investigates the effect of number and size of weight‐loss targets on long‐term weight loss in a large community sample of adults.

Methods

Weight change, attendance and target weight data for all new UK members, joining from January to March 2012, were extracted from a commercial slimming organisation's electronic database.

Results

Of the 35 380 members who had weight data available at 12 months after joining, 69.1% (n = 24 447) had a starting body mass index (BMI) ≥30 kg m^–2. Their mean (SD) weight loss was 12.9% (7.8%) and, for both sexes, weight loss at 12 months was greater for those who set targets (P < 0.001). Those that set ≥4 targets achieved the greatest loss (P < 0.001). The odds ratio for weight loss ≥10% at 12 months was 10.3 (95% confidence interval = 9.7–11.1, P < 0.001) where targets had been set compared to none. At the highest quintile of target size, the size of the first target explained 47.2% (P < 0.001) of the variance in weight loss achieved at 12 months. The mean (SD) BMI reduction in those with a target >25% was 7.6 (4.0) kg m^–2. A higher percentage of obese members did not set targets (P < 0.001) compared to those with a BMI <30 kg m^–2.

Conclusions

Much of the variance in weight loss achieved in this population was explained by the number of targets set and the size of the first target. Although obese people were less likely to set targets, doing so increased the likelihood of achieving clinically significant weight loss and, for some ‘unrealistic’ targets, improved the results.

Enrollment and Disenrollment Experiences of Families Covered by CHIP

OBJECTIVE

To understand why families enroll in and disenroll from Children's Health Insurance Program (CHIP), their experience with the CHIP application and renewal process, and the insurance coverage of their children after disenrolling.

METHODS

We conducted a large household telephone survey in 2012 of CHIP enrollees and disenrollees in 10 states. We used survey responses to assess the perceptions and experiences of families with the CHIP application and renewal process. In addition, we combined the survey data with CHIP/Medicaid administrative data to analyze coverage outcomes of children after disenrolling.

RESULTS

A large majority of recent CHIP enrollees had positive impressions of the application process; 89% found the process very or somewhat easy, and 90% of those receiving assistance found it very helpful. Families had similarly favorable impressions of the renewal process, including those recently disenrolling from CHIP. After disenrolling, children were far more likely to gain Medicaid coverage (49%) than private insurance (18%), while a sizable percentage were uninsured (32%). The likelihood of becoming uninsured was especially high among 18- and 19-year-olds (62%), who lost CHIP coverage due to their age.

CONCLUSIONS

Satisfaction with the CHIP application and renewal process is high among those with recent coverage, consistent with efforts by many states to simplify these processes for families. Medicaid is a critical source of coverage for those leaving CHIP, a role that may only increase as states expanding Medicaid through the Affordable Care Act create a new coverage option for older teens losing CHIP eligibility.

Program Churning and Transfers Between Medicaid and CHIP

OBJECTIVE

In the 10 states that are the focus of the Children's Health Insurance Program Reauthorization Act of 2009 evaluation, we analyze in detail the states' recent progress in retaining children in public coverage and public coverage churning.

METHODS

We used administrative data spanning a five-and-a-half-year period collected from 10 study states-Alabama, California, Florida, Louisiana, Michigan, New York, Ohio, Texas, Utah, and Virginia-to analyze the extent to which children return to the same program a short time after disenrollment and the extent to which transfers between Medicaid and Children's Health Insurance Program (CHIP) lead to public coverage gaps.

RESULTS

Our analysis yielded 3 key findings. First, many children moved between Medicaid and CHIP; while most transitioned seamlessly, coverage gaps occurred for as many as 40%, depending on the type of transition. Second, churning continued to be a concern for public coverage programs, with approximately 21% of Medicaid disenrollees and 10% of separate CHIP disenrollees returning to the same program within 7 months. Third, we found sizable differences in rates of program churning and nonseamless program transfers across the 10 study states.

CONCLUSIONS

Notable variation existed across programs and states, which persisted over the period in public program churning. These results suggest the need for continued efforts to simplify renewal processes, particularly in state Medicaid programs, along with the adoption of processes that improve coordination across programs and policies that simplify these transfers.

Granular dynamics during impact

We study the impact of a projectile onto a bed of 3 mm grains immersed in an index-matched fluid. We vary the amount of prestrain on the sample, strengthening the force chains within the system. We find this affects only the prefactor of the linear depth-dependent term in the stopping force. We propose a simple model to account for the strain dependence of this term, owing to increased pressure in the pile. Interestingly, we find that the presence of the fluid does not affect the impact dynamics, suggesting that dynamic friction is not a factor. Using a laser sheet scanning technique to visualize internal grain motion, we measure the trajectory of each grain throughout an impact. Microscopically, our results indicate that weaker initial force chains result in more irreversible, plastic rearrangements, suggesting static friction between grains does play a substantial role in the energy dissipation.

Evaluation of a low-cost commercially available extraction device for assessing lead bioaccessibility in contaminated soils

The U.S. EPA's in vitro bioaccessibility (IVBA) method 9200.1-86 defines a validated analytical procedure for the determination of lead bioaccessibility in contaminated soils. The method requires the use of a custom-fabricated extraction device that uses a heated water bath for sample incubation. In an effort to improve ease of use, increase sample throughput, and reduce equipment acquisition and maintenance costs, an alternative low-cost, commercially available extraction device capable of sample incubation via heated air and end-over-end rotation was evaluated. An intra-laboratory study was conducted to compare lead bioaccessibility values derived using the two extraction devices. IVBA values were not statistically different (α = 0.05) between the two extraction devices for any of the soils (n = 6) evaluated in this study, with an average difference in mean lead IVBA of 0.8% (s.d. = 0.5%). The commercially available extraction device was able to generate accurate lead IVBA data as compared to the U.S. EPA's expected value for a National Institute of Standards and Technology standard reference material soil. The relative percent differences between high and low IVBA values for each soil, a measure of instrument precision, were also not statistically different (α = 0.05) between the two extraction devices. The statistical agreement of lead IVBA values observed using the two extraction devices supports the use of a low-cost, commercially available extraction device as a reliable alternative to a custom-fabricated device as required by EPA method 9200.1-86.

DEVELOPMENT OF INDICATORS TO MEASURE

This paper describes a study to capture the key roles and activities of nephrology nurses across different countries in Europe. The concept of the study and the need to clarify the activities of the nephrology nurse arose as part of a larger study to develop the European Practice Database (EPD) (1). The Research Board (EDTNA/ERCA) needed to identify key questions that would detect significant differences in the role and responsibilities of nephrology nurses in different countries and monitor the evolution over time of nephrology nursing practice in Europe. It was therefore appropriate to devise a separate small study to generate evidence based questions for the EPD and confirm the reliability and usefulness of the information captured.

INFECTION CONTROL PRACTICE ACROSS EUROPE: RESULTS OF THE EPD

The European Practice Database (EPD) project, developed by the EDTNA/ERCA Research Board, collects data on renal practice at centre level in different European countries. Results presented in this paper focus on infection control practice in haemodialysis centres from 8 different European countries or regions following data collection from 2002 up to 2004. The prevalence of hepatitis B (HBV), hepatitis C (HCV), human immune deficiency (HIV) and methicillin-resistant staphylococcus Aureus (MRSA) was studied as well as the use of screening and preventive actions. These results will enable international comparison in practice and will stimulate further research and the development of new practice recommendations.

TRANSPLANT PRACTICE IN EUROPE: SELECTION OF PATIENTS

This paper reports the findings from the European Practice Database project (1) providing an overview of transplant practice in Europe and patient selection. From the 276 centres surveyed 25 recorded performing patient transplants across eight different countries. The overall figures indicate that the waiting list for transplants is made up of 38% women and 9% of patients above the age of 65 years. All countries offered pre-transplant counselling and screening and post-transplant follow-up, but the extent to which these activities occurred varied. The waiting/transplant ratio ranged from one in Norway to eight in Slovakia. Differences still exist as a result of country specific policies and legislation regarding transplantation.

COMPARISON OF RENAL CARE PRACTICE IN EUROPE: CENTRE AND PATIENT CHARACTERISTICS

The European Practice Database (EPD) contains data from 8 countries including 276 centres and 21,861 dialysis patients. Comparing patients and centre characteristics, remarkable similarities and pronounced differences in renal practice between different European countries and between centres within each country were found.

SERO-CONVERSION OF HCV NEGATIVE PATIENTS: A EUROPEAN STUDY ON SERO-CONVERSION OF HCV NEGATIVE PATIENTS: A EUROPEAN STUDY ON

This paper reports part of the findings from a larger study reported earlier, the European study on epidemiology and the management of HCV in the haemodialysis population (1). Centres recruited to the larger study were monitored for a further one year observation period to measure and generate a deeper understanding of HCV sero-conversion. From 4724 patients who were studied at the baseline, in 68 centres, only 13 patients were found to have sero-converted. These sero-conversions occurred in 7 hospitals within 5 different countries. Possible routes of transmission and risk factors are described with respect to the individual centres and good practice recommendations based on current evidence presented.

Randomized, placebo-controlled trial of propranolol added to topiramate in chronic migraine

OBJECTIVE

To assess the efficacy and safety of adding propranolol to topiramate in chronic migraine subjects inadequately controlled with topiramate alone.

METHODS

This was a double-blind, placebo-controlled, randomized clinical trial conducted through the National Institute of Neurological Disorders and Stroke Clinical Research Collaboration, expected to randomize 250 chronic migraine subjects inadequately controlled (≥10 headaches/month) with topiramate (50-100 mg/day) to either propranolol LA (long acting) (240 mg/day) or placebo. Primary outcome was 28-day moderate to severe headache rate reduction at 6 months (weeks 16 to 24) compared with baseline (weeks -4 to 0).

RESULTS

A planned interim analysis was performed after 48 sites randomized 171 subjects. The data and safety monitoring board recommended ending the trial after determining that it would be highly unlikely for the combination to result in a significant reduction in 28-day headache rate compared with topiramate alone if all 250 subjects were randomized. No safety concerns were identified. At study closure, 191 subjects were randomized. The 6-month reduction in moderate to severe 28-day headache rate and total 28-day headache rate for combination therapy vs topiramate alone was not significantly different: 4.0 vs 4.5 days (moderate to severe 28-day headache rate; p = 0.57) and 6.2 vs 6.1 days (total 28-day headache rate; p = 0.91).

CONCLUSIONS

This study does not provide evidence that the addition of propranolol LA to topiramate adds benefit when chronic migraine is inadequately controlled with topiramate alone.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that propranolol LA, added to topiramate, is ineffective in chronic migraine patients who fail topiramate monotherapy.

The experiences of cancer patients

OBJECTIVES

To assess the needs of cancer patients for information about their condition and to understand the psychological impact of their illness.

BACKGROUND

The discussion of prognosis and treatment options in the palliative setting is an important and difficult part of oncology practice. To evaluate this, we examined the experiences of cancer patients of the physical and psychological impact of their disease on their life, and their opinions on the communication of end-of-life decisions and treatment options.

METHODS

A patient questionnaire was designed that encompassed communication regarding treatment and prognosis, quality-of-life attitudes subsequent to cancer diagnosis, end-of-life care and cancer drug funding. One hundred and twenty-five patients with a diagnosis of cancer were asked to participate and 96 questionnaires were completed and available for analysis. The questionnaire consisted of 63 questions and was completed in both an inpatient and outpatient setting.

RESULTS

This survey brought to light a number of controversial issues in cancer service provision, highlighting the emotional and psychological changes brought about by a cancer diagnosis. Major concerns of our patients include fear of death and pain, changes in interpersonal relationships and financial constraints. Only 66% of the patients wanted to be given a prognosis by their clinicians and just 70% of the patients recalled being given a detailed prognosis. 11% of the patients were not prepared to undergo palliative treatment. In all, 7% were not prepared to accept treatment for 1 year and 2% for 5 years of life in exchange for the potential side effects of cytotoxic chemotherapy. 12% of the patients would not want to be in possession of the information that they were in the terminal phase of the illness with a short time to live and 16% would not want this discussed with their next of kin.

CONCLUSION

This study informs medical professionals about the importance of tailoring information to the needs of the individual patient, and we feel it provides insights into the successes and failures of our communication with cancer patients. It is important that difficult discussions are personalized to the individual patients' wishes. These can vary dramatically both in the area of disclosure of bad news in prognosis and in end-of-life decision making. This study provides compelling evidence for good advanced care planning at an early stage in the management of patients with terminal cancers.

Validation and use of a parametric model for projecting cystic fibrosis survivorship beyond observed data: a birth cohort analysis

Background

The current lifetable approach to survival estimation is favoured by CF registries. Recognising the limitation of this approach, we examined the utility of a parametric survival model to project birth cohort survival estimates beyond the follow-up period, where short duration of follow-up meant median survival estimates were indeterminable.

Methods

Parametric models were fitted to observed survivorship data from the US CF Foundation (CFF) Patient Registry 1980–1994 birth cohort. Model-predicted median survival was estimated. The best fitting model was applied to a Cystic Fibrosis Registry of Ireland dataset to allow an evaluation of the model's ability to estimate predicted median survival. This involved a comparison of birth cohort lifetable predicted and observed (Kaplan–Meier) median survival estimates.

Results

A Weibull model with main effects of gender and birth cohort was developed using a US CFF dataset (n=13 115) for which median survival was not directly estimable. Birth cohort lifetable predicted median survival for male and female patients born between 1985 and 1994 and surviving their first birthday was 50.9 and 42.4 years respectively. To evaluate the accuracy of a Weibull model in predicting median survival, a model was developed for the 1980–1984 Cystic Fibrosis Registry of Ireland birth cohort (n=243), which had an observed (Kaplan–Meier) median survival of 27.7 years. Model-predicted median survival estimates were calculated using data censored at different follow-up periods. The estimates converged to the true value as length of follow-up increased.

Conclusions

Accurate prognostic information that is clinically critical for care of patients affected by rare, life-limiting disorders can be provided by parametric survival models. Problems associated with short duration of follow-up for recent birth cohorts can be overcome using this approach, providing better opportunities to monitor survival and plan services locally.

Location, location, location: important for jet-lagged circadian loops

It is now believed that frequent jet lag or shifts of daily rhythms caused by rotating shift work can lead to deleterious health outcomes. Indeed, many serious health problems, including breast cancer, stroke, and cardiovascular disease, have been linked to an occupational history of shift work. This has heightened interest in better understanding the biological responses to jet lag and shift work, with the hope that this will pave the way to developing compounds that can help people avoid their negative health consequences. In this context, a report in this issue of the JCI takes us to a new level of understanding of the molecular control of the resetting of the multitude of internal biological clocks disrupted in a mouse model of jet lag.

Delayed cystic fibrosis presentation in children in the absence of newborn screening

Newborn cystic fibrosis (CF) screening facilitates early diagnosis and nutritional intervention, which prevents malnourishment and improves growth in childhood. To provide baseline information on the natural history of CF in the Republic of Ireland, where newborn screening has not yet been introduced and CF incidence is high (1:1353 live births), we examined the effect of presentation mode, symptom type and gender on age at diagnosis. Median age at diagnosis was calculated by gender and for presentation mode/symptom type for 601 CF registry children diagnosed 1986-2007. Modes of presentation were each significantly associated with delayed presentation. An adjusted odds ratio of 4.5 (95% CI: 1.8, 11.1) was determined for presentation with family history, 43.1 for gastrointestinal symptoms presentation (95% CI: 18.3, 101.4), 96.9 for both respiratory and gastrointestinal symptoms (95% CI: 38.6, 243,4), and 115.4 for respiratory symptoms (95% CI: 45.2, 294.7). Children with respiratory symptoms had the greatest likelihood of delayed diagnosis (median age: 20.4 months), followed by those with respiratory and gastrointestinal symptoms (9.2 months). Gender was not significantly associated with a delayed presentation when presentation mode was taken into account.

Nonheme-iron absorption in first-degree relatives is highly correlated: a stable-isotope study in mother-child pairs

BACKGROUND

Iron absorption in humans is highly variable even after iron status and dietary components that influence iron absorption are controlled for. Inherited factors may help explain this variance.

OBJECTIVE

Our objective was to compare nonheme-iron absorption from a noninhibitory, stable-isotope-labeled test meal in preschool-aged children and their mothers.

DESIGN

We provided 72 test meals based on degermed maize flour and milk powder and fortified with [(57)Fe]ferrous fumarate or [(58)Fe]ferrous sulfate to healthy Mexican preschool children [n = 18; mean (+/-SD) age: 3.6 +/- 1.0 y] and their mothers [n = 18; mean (+/-SD) age: 28.0 +/- 5.2 y]. Iron absorption was calculated on the basis of incorporation of isotopes into erythrocytes after 14 d and was adjusted for differences in iron status.

RESULTS

There was a wide variation in iron absorption from the test meals: in the mothers and children, the median fractional absorption of ferrous sulfate was 22.55% (range: 1.65-54.83%) and 5.51% (range: 2.23-17.20%), respectively (P < 0.0001). After adjustment for serum ferritin, the significant difference in absorption between mothers and their children disappeared. Despite this broad range of iron absorption, corrected fractional iron absorption from the ferrous fumarate-fortified (r(2) = 0.582) and the ferrous sulfate-fortified test meals (r(2) = 0.557) was strongly correlated in mothers and their children (P < 0.0001). There was a striking positive correlation between the mean corrected fractional iron absorption from both test meals in mothers and their children (r(2) = 0.782, P < 0.0001). In regression analyses that included age, sex, and hemoglobin, the only significant predictor of corrected fractional iron absorption in children was corrected fractional iron absorption in their mothers (standardized beta = 0.884, P < 0.001).

CONCLUSIONS

Nonheme-iron absorption exhibits a strong familial tendency. After differences in meal matrix and serum ferritin are accounted for, these data suggest that inheritance and/or shared environmental factors explain most of the variance in dietary iron absorption.

How research can help control tuberculosis

Tuberculosis (TB) has played a central role in the history of biomedical science from Koch onwards. Research in the nineteenth and twentieth centuries yielded extremely valuable diagnostic, therapeutic and preventive tools for the control of TB. Following the development of shortcourse chemotherapy in the 1970s and 1980s, research into TB virtually evaporated. Despite the availability of an array of tools, TB control faltered, and the disease remains a major killer. The failure of the fruits of scientific research to control TB is a result of the shortcomings of the tools themselves as well the inadequate application of the tools in populations burdened by TB. A changing epidemiologic situation, with escalating rates of human immunodeficiency virus-related TB and the emergence of multidrug-resistant TB, further threatens global TB control. A robust TB research enterprise will be required to meet the global goals for controlling TB in the twentyfirst century. Basic research is needed to better understand its pathogenesis and immunology, and to identify targets for diagnostics, drugs and vaccines. Research into better biomedical tools to detect, treat and prevent TB is also a major priority, as all of the existing tools have important shortcomings. In addition, research into understanding how to apply both existing and new tools to control TB at the population level is urgently needed. Global funding for TB research, $483 million in 2007, is slowly growing but is far behind need. To meet the ambitious goals of the Global Plan to Stop TB and the Millennium Development Goals, a massive investment in research will be necessary.

How research can help control tuberculosis

Tuberculosis (TB) has played a central role in the history of biomedical science from Koch onwards. Research in the nineteenth and twentieth centuries yielded extremely valuable diagnostic, therapeutic and preventive tools for the control of TB. Following the development of short-course chemotherapy in the 1970s and 1980s, research into TB virtually evaporated. Despite the availability of an array of tools, TB control faltered, and the disease remains a major killer. The failure of the fruits of scientific research to control TB is a result of the shortcomings of the tools themselves as well the inadequate application of the tools in populations burdened by TB. A changing epidemiologic situation, with escalating rates of human immunodeficiency virus-related TB and the emergence of multidrug-resistant TB, further threatens global TB control. A robust TB research enterprise will be required to meet the global goals for controlling TB in the twenty-first century. Basic research is needed to better understand its pathogenesis and immunology, and to identify targets for diagnostics, drugs and vaccines. Research into better biomedical tools to detect, treat and prevent TB is also a major priority, as all of the existing tools have important shortcomings. In addition, research into understanding how to apply both existing and new tools to control TB at the population level is urgently needed. Global funding for TB research, $483 million in 2007, is slowly growing but is far behind need. To meet the ambitious goals of the Global Plan to Stop TB and the Millennium Development Goals, a massive investment in research will be necessary.

Prevention of hospitalization due to respiratory syncytial virus: results from the Palivizumab Outcomes Registry

OBJECTIVE

The Palivizumab Outcomes Registry contains data on infants and young children who received palivizumab for the prevention of respiratory syncytial virus (RSV) that causes serious lower respiratory tract illness.

STUDY DESIGN

Prospective observational registry enrolling those who received >or=1 dose of palivizumab during any RSV season (2000 to 2004) at participating US sites.

RESULT

Of 19 548 subjects enrolled, 40% were born before 32 weeks', 48% between 32 and 35 weeks' and 12% after 35 weeks' gestation. Risk factors included child-care attendance, prematurity, chronic lung disease (CLD) and congenital heart disease (CHD). The RSV hospitalization rate of palivizumab recipients was 1.3%. Gender, gestational age <32 weeks, CLD, CHD, congenital airway abnormality, severe neuromuscular disease, Medicaid insurance and >2 children in household were associated with significantly higher rates. Home-care prophylaxis with palivizumab was associated with reduced hospitalization rates.

CONCLUSION

Data on the use of palivizumab prophylaxis in primarily high-risk infants confirm low RSV hospitalization rates.

What would encourage blood donation in Ireland?

BACKGROUND

Recent changes have resulted in the loss of 4% of the donor panel in the Republic of Ireland and 3% in Northern Ireland. In order to increase the number of donors in these two regions, it is important that transfusion service providers explore and understand the reasons, which prevent individuals from donating. The aim of this study was to explore these issues particularly in non-donors and those who had lapsed.

METHODS

This 7-month all-Ireland study was conducted by computer-assisted telephone interview. Data collected included sociodemographic history, donation status, as well as barriers/deterrents to donation.

RESULTS

There were 4166 completed questionnaires (44% donors; 56% non-donors). Of the donors, 13% had donated blood within the last 2 years. Current donors cited 'awareness of patients needs' (88%), 'trust in the blood transfusion service' (70%), and 'an advertising campaign' (70%) as reasons encouraging them to donate blood. Lapsed donors and non-donors cited 'more frequent mobile clinics/sessions' (30% lapsed donors; 53% non-donors), 'if I was asked' (28% lapsed donors; 53% non-donors), and 'more flexible opening hours' (23% lapsed donors; 44% non-donors) as reasons that would encourage them to donate. The main reasons cited by non-donors for never having donated included 'medical reasons' (41% Republic of Ireland; 43% Northern Ireland), 'lack of information' (20% Republic of Ireland; 22% Northern Ireland), 'fear of needles' (15% Republic of Ireland; 17% Northern Ireland), and 'time constraints' (12% Republic of Ireland; 13% Northern Ireland). Among the non-donor group, 10% (Republic of Ireland) and 6% (Northern Ireland) claimed that they are not permitted to donate.

CONCLUSION

Replacing regular donors is a major challenge for the transfusion service providers. This study shows that by facilitating the general public by introducing more mobile clinics/sessions, more flexible opening hours and having a better level of knowledge in the community about blood donation may encourage lapsed donors and new donors to become regular donors.

Behavioral and neurochemical sources of variability of circadian period and phase: studies of circadian rhythms of npy-/- mice

The cycle length or period of the free-running rhythm is a key characteristic of circadian rhythms. In this study we verify prior reports that locomotor activity patterns and running wheel access can alter the circadian period, and we report that these treatments also increase variability of the circadian period between animals. We demonstrate that the loss of a neurochemical, neuropeptide Y (NPY), abolishes these influences and reduces the interindividual variability in clock period. These behavioral and environmental influences, from daily distribution of peak locomotor activity and from access to a running wheel, both act to push the mean circadian period to a value < 24 h. Magnitude of light-induced resetting is altered as well. When photoperiod was abruptly changed from a 18:6-h light-dark cycle (LD18:6) to LD6:18, mice deficient in NPY were slower to respond to the change in photoperiod by redistribution of their activity within the prolonged dark and eventually adopted a delayed phase angle of entrainment compared with controls. These results support the hypothesis that nonphotic influences on circadian period serve a useful function when animals must respond to abruptly changing photoperiods and point to the NPYergic pathway from the intergeniculate leaflet innervating the suprachiasmatic nucleus as a circuit mediating these effects.

Emerging advantages and drawbacks of telephone surveying in public health research in Ireland and the U.K

BACKGROUND

Telephone surveys have been used widely in public health research internationally and are being increasingly used in Ireland and the U.K.

METHODS

This study compared three telephone surveys conducted on the island of Ireland from 2000 to 2004, examining study methodology, outcome measures and the per unit cost of each completed survey. We critically examined these population-based surveys which all explored health related attitudes and behaviours.

RESULTS

Over the period from 2000 to 2005 the percentage of calls which succeeded in contacting an eligible member of the public fell, from 52.9% to 31.8%. There was a drop in response rates to the surveys (once contact was established) from 58.6% to 17.7%. Costs per completed interview rose from 4.48 euro to 15.65 euro. Respondents were prepared to spend 10-15 minutes being surveyed, but longer surveys yielded poorer completion rates. Respondents were willing to discuss issues of a sensitive nature. Interviews after 9 pm were less successful, with complaints about the lateness of the call. Randomisation from electronic residential telephone directory databases excluded all ex-directory numbers and thus was not as representative of the general population as number generation by the hundred-bank method. However the directory database was more efficient in excluding business and fax numbers.

CONCLUSION

Researchers should take cognisance of under-representativeness of land-line telephone surveys, of the increasing difficulties in contacting the public and of mounting personnel costs. We conclude that telephone surveying now requires additional strategies such as a multimode approach, or incentivisation, to be a useful, cost-effective means of acquiring data on public health matters in Ireland and the U.K.

European study on epidemiology and management of hepatitis C virus (HCV) infection in the haemodialysis population. Part 3: prevalence and incidence

An analysis of the literature showed a high prevalence of HCV in the European dialysis population in the nineties. The prevalence was similar in most countries in northern Europe, but infection was more common in France, Italy, Spain, Portugal and Greece (1) and in Eastern European countries (2). The reported prevalence of anti-HCV-positive patients in the EDTA registry was 21% in 1992 and 18% in 1993 (3) ranging from 1% in Finland to 42% in Egypt (4). The incidence of HCV, in new patients starting renal replacement therapy, ranged from 3% to 7% (5,6) and reported seroconversion rates during dialysis treatment varied between 1% (7) and 16% (8) per year.