Addressing the pitfalls when designing intervention studies to discover and validate biomarkers of habitual dietary intake

INTRODUCTION

Dietary exposure monitoring within populations is reliant on self-reported measures such as Food Frequency Questionnaires and diet diaries. These methods often contain inaccurate information due to participant misreporting, non-compliance and bias. Urinary metabolites derived from individual foods could provide additional objective indicators of dietary exposure. For biomarker approaches to have utility it is essential that they cover a wide-range of commonly consumed foods and the methodology works in a real-world environment.

OBJECTIVES

To test that the methodology works in a real-world environment and to consider the impact of the major sources of likely variance; particularly complex meals, different food formulations, processing and cooking methods, as well as the dynamics of biomarker duration in the body.

METHODS

We designed and tested a dietary exposure biomarker discovery and validation strategy based on a food intervention study involving free-living individuals preparing meals and collecting urine samples at home. Two experimental periods were built around three consecutive day menu plans where all foods and drinks were provided (n = 15 and n = 36).

RESULTS

The experimental design was validated by confirming known consumption biomarkers in urinary samples after the first menu plan. We tested biomarker performance with different food formulations and processing methods involving meat, wholegrain, fruits and vegetables.

CONCLUSION

It was demonstrated that spot urine samples, together with robust dietary biomarkers, despite major sources of variance, could be used successfully for dietary exposure monitoring in large epidemiological studies.

Political transition and emergent forest-conservation issues in Myanmar

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.

De novo transcriptome assembly for the spiny mouse (Acomys cahirinus)

Spiny mice of the genus Acomys display several unique physiological traits, including menstruation and scar-free wound healing; characteristics that are exceedingly rare in mammals, and of considerable interest to the scientific community. These unique attributes, and the potential for spiny mice to accurately model human diseases, are driving increased use of this genus in biomedical research, however little genetic information is accessible for this species. This project aimed to generate a draft transcriptome for the Common spiny mouse (Acomys cahirinus). Illumina sequencing of RNA from 15 organ types (male and female) produced 451 million, 150 bp paired-end reads (92.4Gbp). An extensive survey of de novo transcriptome assembly approaches using Trinity, SOAPdenovo-Trans, and Oases at multiple kmer lengths was conducted, producing 50 single-kmer assemblies from this dataset. Non-redundant transcripts from all assemblies were merged into a meta-assembly using the EvidentialGene tr2aacds pipeline, producing the largest gene catalogue to date for Acomys cahirinus. This study provides the first detailed characterization of the spiny mouse transcriptome. It validates use of the EvidentialGene tr2aacds pipeline in mammals to augment conventional de novo assembly approaches, and provides a valuable scientific resource for further investigation into the unique physiological characteristics inherent in the genus Acomys.

Enrichment of Retroviral Sequences in Brain Tissue from Patients with Severe Demyelinating Diseases

Background

Our group has used deep sequencing to identify viral RNA signatures in human brain specimens. We have previously used this method to detect HSV1, GBV-C, and measles virus sequence in brain tissue from deceased donors. Deep sequencing was performed on brain specimens from a cohort of patients who died with progressive forms of MS, revealing evidence of increased expression of some human endogenous retrovirus (HERV) domains.

Objectives

Identify RNA sequences and new antigens involved in the pathogenesis of MS

Methods

Deep sequencing was performed on RNA extracted from 12 progressive MS, 2 neuromyelitis optica (MS/NMO = demyelination group), 14 normal control, and 7 other neurologic disease (OND) control frozen brain specimens. The resulting single-ended 50 bp sequences (reads) were compared to a non redundant viral database representing (NRVDB) all 1.2 M viral records in GenBank. A retroviral gene catalog (RVGC) was prepared by identifying human genetic loci (GRCh37.p13) homologous to domains contained in the Gypsy 2.0 retro element database. Reads were aligned to the RVGC and human transcriptome with Bowtie2. The resulting viral hit rates (VHRs) were normalized by the number of high quality reads. The expression of human genes, including HERVs, was determined using Cufflinks. Comparisons between the groups were performed using the false discovery rate.

Results

Fifty to 131 million high quality reads per specimen were obtained. Comparison of the reads to the NRVDB suggested that the demyelination and OND specimens had higher VHRs against some retroviral sequences compared with the controls. This was confirmed by retroviral domain averaging. Gene expression analysis showed differential expression among some HERV sequences. Single read mapping revealed one envelope and one reverse transcriptase sequence record that were significantly enriched among the demyelination samples compared to the normal controls. Less restrictive (comprehensive) read mapping showed that 2 integrase, 2 core, 2 envelope, and 3 KRAB sequences that were overexpressed in the demyelination group.

Conclusions

These data demonstrate that some endogenous retroviral sequences are significantly overexpressed in these demyelination brain tissue specimens, but the magnitude of this overexpression is small. This is consistent with the concept of HERV activation as a part of the innate immune response.

Modeling birds on wires

In this paper we introduce a mathematical model to study the group dynamics of birds resting on wires. The model is agent-based and postulates attraction-repulsion forces between the interacting birds: the interactions are "topological", in the sense that they involve a given number of neighbors irrespective of their distance. The model is first mathematically analyzed and then simulated to study its main properties: we observe that the model predicts birds to be more widely spaced near the borders of each group. We compare the results from the model with experimental data, derived from the analysis of pictures of pigeons and starlings taken in New Jersey: two different image elaboration protocols allow us to establish a good agreement with the model and to quantify its main parameters. We also discuss the potential handedness of the birds, by analyzing the group organization features and the group dynamics at the arrival of new birds. Finally, we propose a more refined mathematical model that describes landing and departing birds by suitable stochastic processes.

Management of paediatric otogenic cerebral venous sinus thrombosis: a systematic review

BACKGROUND

Otogenic paediatric cerebral venous sinus thrombosis (CVST) is rare but has potential clinical sequelae. Its management has long been debated mainly concerning the role of surgery and the use of anticoagulant therapy.

OBJECTIVE OF REVIEW

To review the current literature and examine the medical and surgical management of paediatric otogenic CVST and its clinical and radiological outcome.

TYPE OF REVIEW

Systematic review.

SEARCH STRATEGY

The electronic databases (MEDLINE, EMBASE, Cochrane) were searched from inception to November 2014 using text words 'cerebral venous sinus thrombosis OR cerebral venous thrombosis OR lateral sinus thrombosis OR sigmoid sinus thrombosis' AND 'otogenic OR mastoiditis OR otitis media' AND 'children OR paediatric OR pediatric'.

EVALUATION METHOD

Inclusion criteria were applied by two reviewers and data extraction was carried out. The type of otological surgery (conservative versus extensive) and the use of anticoagulants with their clinical and radiological outcomes were tabulated.

RESULTS

Thirty-six studies (15 case reports and 21 case series) were included with a total of 190 patients. A total of 92.1% of patients underwent otological surgery, and 69.5% had conservative surgery and 30.5% extensive otological surgery. Anticoagulants were used in 59%. A total of 79.2% of patients were reported to have had a good clinical outcome. Within this group, 56% had conservative surgery and anticoagulants. Follow-up scans were documented in 61.6% of patients and complete recanalisation was observed in 51%. Complete recanalisation was observed in 47% of those who had been anticoagulated and 55% of those who received no anticoagulation.

CONCLUSIONS

Conservative otological surgery with the combination of anticoagulation was the most common treatment modality found in the group of patients with good clinical outcome. However, given the current low level of evidence, a multicentre collaborative study is needed to help establish the optimum surgical approach and the role of anticoagulation in managing paediatric otogenic CVST.

Pharmacist Intervention in Risk Reduction Study in High-Risk Cardiac Patients: The Effect of 2 Methods of Pharmacist Training

Objective:

To assess the effect of intensive vs conventional training on pharmacist-suggested implementation of cardiac risk reduction efforts in community practice.

Methods:

Sixty-one volunteer pharmacists from 40 pharmacies were randomized to 1 of 2 educational groups: intensive or conventional training in cardiac risk reduction. With training complete, pharmacists identified and approached patients at high risk for coronary artery disease (CAD) at their practice sites to participate in the program. After a patient interview, pharmacists documented the relevant CAD risk factors and medication history, and then faxed this information, along with risk reduction recommendations, to the primary care physician. Patients were then encouraged to book a medical appointment for further assessment and treatment, if warranted. Follow-up occurred at 4, 16, and 24 weeks to determine if any pharmacist-suggested risk reduction measures had been implemented. Pharmacists were reimbursed $30 per patient accrued.

Results:

A total of 217 patients were enrolled in the study, and of those, 216 had follow-up data available for analysis. No significant differences were observed between the groups with respect to mean number of patients enrolled per pharmacist (4.3 vs 2.7) and the proportion of pharmacists completing at least 1 patient (17/27 vs 14/34). Feedback from pharmacists on program delivery indicated no significant difference in satisfaction with the training provided. The recommendations forwarded by pharmacists of the intensive group (35.8%) received greater acceptance by physicians than those in the conventional group (23.8%).

Conclusion:

Although results are preliminary, intensive training for pharmacists was more likely to result in improvements in cardiovascular risk reduction therapy than when conventional training was used.

Pharmacist Intervention in Risk Reduction Study: High-Risk Cardiac Patients

Objectives:

Although there are guidelines for managing patients at high vascular risk, many people remain undertreated. This community-based study was designed to 1) measure the ability of the pharmacist—physician collaboration to affect a broad array of drug-related endpoints and 2) to compare 2 methods of training community pharmacists to collaborate with physicians on cardiac patient care. This paper focuses on the first outcome, and a companion paper will address the second outcome.

Methods:

We used a before-and-after design to assess pharmacists' ability to affect drug-related endpoints. We identified patients by various methods, one of which was medication profiles. Those providing consent were educated on risk factor modification and encouraged to consult their physicians. Pharmacists subsequently faxed the details of their assessments to the primary care physician, along with suggestions for therapy changes. Our outcome measure was the proportion of patients who achieved a composite of either a dose increase or a new target medication as a result of pharmacist recommendations during the study.

Results:

A total of 61 pharmacists recruited 217 patients, and of these, follow-up was completed on 216. Of the patients for whom a pharmacist made a suggestion, pharmacologic risk reduction therapy was initiated or enhanced in 53.7%.

Conclusion:

This community pharmacist—based program improved utilization of the therapies known to decrease vascular risk in patients considered high risk.

Recall of Dental Pain and Anxiety in a Cohort of Oral Surgery Patients

Dental patients generally recall more pain than they originally report, with ratings of pain related to state anxiety and dental fear, but the role of depression in recall of dental pain remains uncertain. This study examined the relative contributions of different variables in explaining dental pain recalled after tooth extraction. Patients presenting for tooth extraction, prior to extraction, rated their current dental pain and state anxiety, prediction of pain and state anxiety during extraction, depression, and dental fear. Immediately postprocedure and then 1 mo later, patients rated their pain and state anxiety during extraction. Hierarchical linear regression equations were used to explain variance in recalled pain and state anxiety. In addition, patients were divided into high and low dental fear and depression groups and compared on ratings of pain and state anxiety across time. In a final sample of 157 patients, the most important predictors of recalled pain were pain reported during extraction (β = .53) and recalled state anxiety (β = .52). Dental fear and depression had a significant interaction: only when patients reported less depression did those patients who reported more dental fear also report more pain than patients who reported less dental fear (P < 0.05, ω(2) = .07). Patients who reported more depression entered the dental operatory reporting more pain, but all patients generally reported less pain during extraction than they predicted or recalled. Memory of state anxiety and pain reported during tooth extraction, not depression or state anxiety at the time of extraction, were critical factors in memory of the pain associated with the procedure. At higher levels of depression, patients higher and lower in dental fear did not differ in report of pain. Future studies are needed to further clarify interactions of depression and dental fear over time.