Event Marker Research Articles

Abstract 12644: Growth Differentiation Factor-15 (GDF-15) for Risk Stratification in Patients After an Acute Coronary Syndrome: Insights From the SOLID-TIMI 52 trial

Background: Growth differentiation factor (GDF)-15, a stress responsive cytokine, is associated with the risk of CV events after an acute coronary syndrome (ACS). Unlike other established cardiac biomarkers, the level of GDF-15 remains elevated in sub-acute phase after ACS and gradually decreases over time. We evaluated the prognostic utility of GDF-15 in patients after ACS accounting for established markers and risk predictors. Methods: GDF-15 (R&D Systems) and other established cardiac biomarkers (BNP, hsCRP and hsTnI) were measured at baseline in a randomly selected cohort of 4,968 patients enrolled within 30 days of hospitalization with ACS (median=14d) in SOLID-TIMI 52. Previously defined cutpoints were applied for GDF-15 concentration: <1200 (n=3451), 1200-1800 (n=919), and > 1800 ng/L (n=598). Analyses were adjusted for established risk predictors, days from the ACS event and other markers. MACE was defined as CV death, MI or stroke. Median follow-up was 2.5 years. Results: Patients with higher GDF-15 tended to be older, more likely to have diabetes, hypertension, history of revascularization, and CKD at baseline. Higher baseline levels of GDF-15 identified patients with higher rates of MACE as well as each individual element (p-trend <0.001 for all endpoints, Fig). The rate of MI was ∼2-fold higher in those with GDF-15 concentration >1800ng/L compared to patients with GDF-15 concentration <1200 ng/L. After adjustment for clinical predictors and other markers, GDF-15 was independently associated with the risk of MACE (HR 1.4, 95% CI 1.1-1.7; HR 1.8, 95% CI 1.4-2.3 for GDF-15 1200-1800, >1800, respectively). Individuals with GDF-15 >1800 ng/L had an increased risk of MI (adj HR 1.4, 95% CI 1.1-2.0) and stroke (adj HR 2.3, 95% CI 1.3-3.9). Conclusion: In patients after ACS, GDF-15 concentration is associated with the risk of MACE including MI and stroke independent of traditional risk factors and risk markers.

Abstract 18201: Effects of Epinephrine Administration on Cerebral Oxygenation During Cardiopulmonary Resuscitation

Introduction: Epinephrine has been presumed to improve cerebral oxygen delivery during CPR. Animal studies however have demonstrated that epinephrine-induced capillary vasoconstriction may actually decrease cerebral capillary blood flow and registry studies have suggested that adrenaline may actually worsen neurological outcome, The effects of epinephrine on cerebral oxygenation (rSO2) during CPR has not been documented in the clinical setting. Methods: Following ethics approval, rSO2 was measured continuously using cerebral oximetry in patients undergoing in-hospital cardiac arrest. During CPR, time event markers recorded the administration of 1mg epinephrine. rSO2% values were analysed for a 5 min window prior to and then 5 mins after the first epinephrine administration. Results: A total of 56 epinephrine doses were analyzed in 36 patients during CPR. Results are shown below. The average rSO2% in the 5 mins following epinephrine administration was 1.40% higher (95% CI=0.41-2.40%, P=0.0059) than in the 5 min period prior to epinephrine administration. After adjusting, for patients’ ROSC status, initial rhythm, hemoglobin and Charlson comorbidity index, this difference remained statistically significant (1.42% with 95% CI: 0.35-2.49%, P=0.009). There was no statistically significant difference in the gradient of rSO2% during the 5 min period immediately before (0.88) compared with immediately after (1.09) epinephrine administration. Conclusion: IV administration of 1mg epinephrine during CPR results in minimal changes to rSO2%. This is the first clinical data to demonstrate the effects of epinephrine on rSO2 and is consistent with animal studies. These results may go some way to explaining the limited effect of epinephrine on improving neurological recovery from cardiac arrest.

Instrumented shoes for activity classification in the elderly

Quantifying daily physical activity in older adults can provide relevant monitoring and diagnostic information about risk of fall and frailty. In this study, we introduce instrumented shoes capable of recording movement and foot loading data unobtrusively throughout the day. Recorded data were used to devise an activity classification algorithm. Ten elderly persons wore the instrumented shoe system consisting of insoles inside the shoes and inertial measurement units on the shoes, and performed a series of activities of daily life as part of a semi-structured protocol. We hypothesized that foot loading, orientation, and elevation can be used to classify postural transitions, locomotion, and walking type. Additional sensors worn at the right thigh and the trunk were used as reference, along with an event marker. An activity classification algorithm was built based on a decision tree that incorporates rules inspired from movement biomechanics. The algorithm revealed excellent performance with respect to the reference system with an overall accuracy of 97% across all activities. The algorithm was also capable of recognizing all postural transitions and locomotion periods with elevation changes. Furthermore, the algorithm proved to be robust against small changes of tuning parameters. This instrumented shoe system is suitable for daily activity monitoring in elderly persons and can additionally provide gait parameters, which, combined with activity parameters, can supply useful clinical information regarding the mobility of elderly persons.

Reproducibility of a Standardized Actigraphy Scoring Algorithm for Sleep in a US Hispanic/Latino Population.

While actigraphy is considered objective, the process of setting rest intervals to calculate sleep variables is subjective. We sought to evaluate the reproducibility of actigraphy-derived measures of sleep using a standardized algorithm for setting rest intervals. Observational study. Community-based. A random sample of 50 adults aged 18-64 years free of severe sleep apnea participating in the Sueño sleep ancillary study to the Hispanic Community Health Study/Study of Latinos. N/A. Participants underwent 7 days of continuous wrist actigraphy and completed daily sleep diaries. Studies were scored twice by each of two scorers. Rest intervals were set using a standardized hierarchical approach based on event marker, diary, light, and activity data. Sleep/wake status was then determined for each 30-sec epoch using a validated algorithm, and this was used to generate 11 variables: mean nightly sleep duration, nap duration, 24-h sleep duration, sleep latency, sleep maintenance efficiency, sleep fragmentation index, sleep onset time, sleep offset time, sleep midpoint time, standard deviation of sleep duration, and standard deviation of sleep midpoint. Intra-scorer intraclass correlation coefficients (ICCs) were high, ranging from 0.911 to 0.995 across all 11 variables. Similarly, inter-scorer ICCs were high, also ranging from 0.911 to 0.995, and mean inter-scorer differences were small. Bland-Altman plots did not reveal any systematic disagreement in scoring. With use of a standardized algorithm to set rest intervals, scoring of actigraphy for the purpose of generating a wide array of sleep variables is highly reproducible.

Event Valence Matters : Investigating the Moderating Role of Event Valence on Event Markers’ Systematic Effect

Previous research has revealed that people feel past target events are more distant when they recall more intervening events, event markers, that are both accessible in memory and perceived to be related to that target event (Zauberman, Levav, Diehl, and Bhargave 2010). This phenomenon was called the systematic effect of event markers (SEEM). In this research, we explore the moderating effect of the valence of the target event on SEEM and suggest the difficulty of recalling event markers as the possible mechanism. Study 1 shows that SEEM mainly occur when the valence of the target event is negative rather than positive. Study 2 showed that even though people have more difficulty recalling four event markers than one regardless of event valence, the difficulty of recalling event markers only mediates SEEM when the target event valence is negative. Furthermore, when the target event is positive, SEEM does not exist, confirming that the mediating role of the difficulty of recalling event markers on SEEM is moderated by the valence of the target event.

Event Valence Matters

Previous research has revealed that people feel past target events are more distant when they recall more intervening events, event markers, that are both accessible in memory and perceived to be related to that target event (Zauberman, Levav, Diehl, and Bhargave 2010). This phenomenon was called the systematic effect of event markers (SEEM). In this research, we explore the moderating effect of the valence of the target event on SEEM and suggest the difficulty of recalling event markers as the possible mechanism. Study 1 shows that SEEM mainly occur when the valence of the target event is negative rather than positive. Study 2 showed that even though people have more difficulty recalling four event markers than one regardless of event valence, the difficulty of recalling event markers only mediates SEEM when the target event valence is negative. Furthermore, when the target event is positive, SEEM does not exist, confirming that the mediating role of the difficulty of recalling event markers on SEEM is moderated by the valence of the target event.

Natural tags and markers for tracking and identifying fish

Event Abstract Back to Event Natural tags and markers for tracking and identifying fish Steven Campana1* 1 University of Iceland, Iceland A winning feature of naturally-induced fish tags is their simultaneous appearance on the entire group or population, at no expense to the researcher. The challenge then becomes the search for a marker that is sufficiently distinct that it will allow clear identification of the group of interest. Elemental and isotopic fingerprints, genetic markers, growth patterns recorded in otoliths, and parasites are all examples of natural tags with demonstrated success in identifying and tracking sub-populations, groups and even individuals of teleost fishes. Far less explored are similar applications involving sharks and crustaceans such as lobsters, yet many of the same powerful tracking and identification applications appear to exist for these animals as well. In this talk, I will briefly review some of the established natural tags with proven track records for monitoring the movement of aquatic organisms, before exploring some exciting new possibilities. Keywords: Fishes, otoliths, Movement, population structure, Stock discrimination, Rational management Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Plenary Invited Presentation Topic: Life Cycles, Migration and Connectivity Citation: Campana S (2015). Natural tags and markers for tracking and identifying fish. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.FMARS.2015.03.00228 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 16 Dec 2015; Published Online: 16 Dec 2015. * Correspondence: PhD. Steven Campana, University of Iceland, Reykjavik, Iceland, steven.e.campana@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Steven Campana Google Steven Campana Google Scholar Steven Campana PubMed Steven Campana Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Quantitative methodology is critical for assessing DNA methylation and impacts on correlation with patient outcome.

BackgroundDNA hypermethylation is reported as a frequent event and prognostic marker in head and neck squamous cell carcinomas (HNSCC). Methylation has been commonly assessed with non-quantitative methodologies, such as methylation-specific PCR (MSP). We investigated previously reported hypermethylated genes with quantitative methodology in oral tongue squamous cell carcinomas (OTSCC).ResultsThe methylation status of 12 genes in 115 OTSCC samples was assessed by one or more of three quantitative analyses: methylation sensitive high resolution melting (MS-HRM), sensitive-melting analysis after real time-methylation specific PCR (SMART-MSP), and bisulfite pyrosequencing.In contrast to much of the literature, either no or infrequent locus-specific methylation was identified by MS-HRM for DAPK1, RASSF1A, MGMT, MLH1, APC, CDH1, CDH13, BRCA1, ERCC1, and ATM. The most frequently methylated loci were RUNX3 (18/108 methylated) and ABO (22/107 methylated). Interrogation of the Cancer Genome Atlas (TCGA) HNSCC cohort confirmed the frequency of significant methylation for the loci investigated.Heterogeneous methylation of RUNX3 (18/108) and ABO (22/107) detected by MS-HRM, conferred significantly worse survival (P = 0.01, and P = 0.03). However, following quantification of methylation levels using pyrosequencing, only four tumors had significant quantities (>15%) of RUNX3 methylation which correlated with a worse patient outcome (P <0.001), while the prognostic significance of ABO hypermethylation was lost. RUNX3 methylation was not prognostic for the TCGA cohort (P = 0.76).ConclusionsWe demonstrated the critical need for quantification of methylation levels and its impact on correlative analyses. In OTSCC, we found little evidence of significant or frequent hypermethylation of many loci reported to be commonly methylated. It is likely that previous reports have overestimated the frequency of significant methylation events as a consequence of the use of non-quantitative methodology.Electronic supplementary materialThe online version of this article (doi:10.1186/1868-7083-6-22) contains supplementary material, which is available to authorized users.

Troubleshooting implanted cardioverter defibrillator sensing problems I.

Multicenter studies1–3 demonstrate that unnecessary implanted cardioverter defibrillator (ICD) shocks can be reduced by evidence-based programming of detection rate and duration, antitachycardia pacing, and algorithms that discriminate supraventricular tachycardia (SVT) from ventricular tachycardia (VT). Reducing unnecessary shocks from oversensing has attracted less attention. Excluding patients with recalled leads, ventricular oversensing accounts for 100 000 patients; and, without an alert for oversensing, 50% of lead fractures present with ≥5 shocks.7,8 Thus, oversensing commonly produces severe symptoms, which may cause post-traumatic stress disorder.9 Furthermore, recognition of transient, asymptomatic oversensing may prevent major complications.7,8,10 Other sensing problems also provide challenges for ICDs. These include undersensing of VF, atrial undersensing, and oversensing in relation to SVT–VT discrimination, and unique issues related to sensing subcutaneous electrograms. In ICDs, sensing is usually defined as it is in pacemakers, the process for determining the timing of individual cardiac depolarizations. Correspondingly, detection is the process by which an ICD algorithm classifies a sequence of sensed signals to determine the cardiac rhythm. Thus, sensing typically precedes detection. However, algorithms that identify oversensing may be applied after detection, and subcutaneous ICDs may integrate traditionally distinct features of sensing and detection. This review focuses on ICD sensing problems. ### Electrogram Sources Analysis of sensing begins with ICD electrograms and corresponding annotated event markers (commonly referred to by the trademarked term Marker Channel, Medtronic Inc). ICDs store 2 to 4 channels of electrograms and telemeter them to the programmer. The 2 primary ICD electrograms are the shock or high-voltage electrogram displayed on …

Peri-operative adverse respiratory events in children.

Three quarters of all critical incidents and a third of all peri-operative cardiac arrests in paediatric anaesthesia are caused by adverse respiratory events. We screened for risk factors from children's and their families' histories, and assessed the usefulness of common markers of allergic sensitisation of the airway as surrogates for airway inflammation and increased risk for adverse respiratory events. One hundred children aged up to 16 years with two or more risk factors undergoing elective surgery were included in the study. Eosinophil counts, IgE level, specific IgE for D. pteronyssinus, cat epithelia and Gx2 (grass pollen) were measured for each child and adverse respiratory events (bronchospasm, laryngospasm, oxygen desaturation < 95%, severe persistent coughing, airway obstruction and postoperative stridor) were recorded. Twenty-one patients had an adverse respiratory event but allergic markers were poor predictors. Binary logistic regression showed a lack of predictive value of the eosinophil range and adverse respiratory events (p = 0.249). Receiver operating characteristic (ROC) curves for the presence of adverse respiratory events vs level of specific IgE antibody (to Gx2 (AUC 0.614), cat epithelia (0.564) and D. pteronyssinus (0.520)) demonstrated poor predictive values. However, the presence of risk factors was strongly associated with adverse respiratory events (p < 0.001) and a ROC-curve analysis indicated a fair capacity to predict adverse respiratory events (AUC 0.788). There was a significant difference (p = 0.001) between the presence of adverse respiratory events in patients with more than four (p = 0.006), compared with less than four (p = 0.001), risk factors. We conclude that while risk factors taken from the child's (or family) history proved good predictors of adverse respiratory events, immunological markers of allergic sensitisation demonstrated low predictive values. Pre-operative identification of children at high risk for an adverse respiratory event should rely on clinical, rather than immunological, assessment.

A toolbox for residue iteration decomposition (RIDE)—A method for the decomposition, reconstruction, and single trial analysis of event related potentials

BackgroundConventionally, event-related brain potentials (ERPs) are obtained by averaging a number of single trials. This can be problematic due to trial-to-trial latency variability. Residue iteration decomposition (RIDE) was developed to decompose ERPs into component clusters with different latency variability and to re-synchronize the separated components into a reconstructed ERP. New methodRIDE has been continuously upgraded and now converges to a robust version. We describe the principles of RIDE and detailed algorithms of the functional modules of a toolbox. We give recommendations and provide caveats for using RIDE from both methodological and psychological perspectives. ResultsRIDE was applied to several data samples to demonstrate its ability to decompose and reconstruct latency-variable components of ERPs and to retrieve single trial variability information. Different functionalities of RIDE were shown in appropriate examples. Comparison with existing methodsRIDE employs several modules to achieve a robust decomposition of ERP. As main innovations RIDE (1) is able to extract components based on the combination of known event markers and estimated latencies, (2) prevents distortions much more effectively than previous methods based on least-square algorithms, and (3) allows time window confinements to target relevant components associated with sub-processes of interest. ConclusionsRIDE is a convenient method that decomposes ERPs and provides single trial analysis, yielding rich information about sub-components, and that reconstructs ERPs, more closely reflecting the combined activity of single trial ERPs. The outcomes of RIDE provide new dimensions to study brain–behavior relationships based on EEG data.

Nonadherence with antipsychotic medication in schizophrenia: challenges and management strategies.

Nonadherence with medication occurs in all chronic medical disorders. It is a particular challenge in schizophrenia due to the illness’s association with social isolation, stigma, and comorbid substance misuse, plus the effect of symptom domains on adherence, including positive and negative symptoms, lack of insight, depression, and cognitive impairment. Nonadherence lies on a spectrum, is often covert, and is underestimated by clinicians, but affects more than one third of patients with schizophrenia per annum. It increases the risk of relapse, rehospitalization, and self-harm, increases inpatient costs, and lowers quality of life. It results from multiple patient, clinician, illness, medication, and service factors, but a useful distinction is between intentional and unintentional nonadherence. There is no gold standard approach to the measurement of adherence as all methods have pros and cons. Interventions to improve adherence include psychoeducation and other psychosocial interventions, antipsychotic long-acting injections, electronic reminders, service-based interventions, and financial incentives. These overlap, all have some evidence of effectiveness, and the intervention adopted should be tailored to the individual. Psychosocial interventions that utilize combined approaches seem more effective than unidimensional approaches. There is increasing interest in electronic reminders and monitoring systems to enhance adherence, eg, Short Message Service text messaging and real-time medication monitoring linked to smart pill containers or an electronic ingestible event marker. Financial incentives to enhance antipsychotic adherence raise ethical issues, and their place in practice remains unclear. Simple pragmatic strategies to improve medication adherence include shared decision-making, regular assessment of adherence, simplification of the medication regimen, ensuring that treatment is effective and that side effects are managed, and promoting a positive therapeutic alliance and good communication between the clinician and patient. These elements remain essential for all patients, not least for the small minority where vulnerability and risk issue dictate that compulsory treatment is necessary to ensure adherence.

Embolic Activity During In Vivo Cardiopulmonary Bypass

Neurologic injury after cardiac surgery is principally associated with emboli. Although much work has focused on surgical sources of emboli, less attention has been focused on emboli associated with the heart–lung machine. We tested whether emboli are associated with discrete processes during cardiopulmonary bypass (CPB). One hundred patients undergoing cardiothoracic surgery were enrolled between April 2008 and May 2011 at a single medical center. During each surgical procedure, emboli were counted in three CPB locations: the venous side (Channel 1), before the arterial line filter (Channel 2), and after the arterial line filter (Channel 3). We used prespecified event markers to identify perfusionist interventions. Identical circuits were used on all patients. Of the 100 patients enrolled, 62 underwent isolated coronary artery bypass grafting (CABG), 17 underwent isolated valve operations, and 21 underwent CABG plus valve. Median counts across Channels 1, 2, and 3 were 69,853, 3,017, and 1,251, respectively. The greatest contributor to emboli in Channels 1, 2, and 3, respectively, were achieving the calculated CPB flow, opening of the electronic arterial line clamp, and introducing a hemofilter. The circuit technology was efficient in reducing total emboli counts from Channels 1–2 irrespective of the size of the emboli. Nearly 71% of all emboli 30–100 mm in size were removed from the circuit between Channels 2 and 3. No significant association was found between emboli counts and S100B release. Emboli occur frequently during CPB and are predominantly associated with the initiation of bypass, operation of the electronic arterial line clamp, and the initiation of a hemofilter. Continued work to reduce the occurrence of emboli is warranted.

MoBILAB: an open source toolbox for analysis and visualization of mobile brain/body imaging data

A new paradigm for human brain imaging, mobile brain/body imaging (MoBI), involves synchronous collection of human brain activity (via electroencephalography, EEG) and behavior (via body motion capture, eye tracking, etc.), plus environmental events (scene and event recording) to study joint brain/body dynamics supporting natural human cognition supporting performance of naturally motivated human actions and interactions in 3-D environments (Makeig et al., 2009). Processing complex, concurrent, multi-modal, multi-rate data streams requires a signal-processing environment quite different from one designed to process single-modality time series data. Here we describe MoBILAB (more details available at sccn.ucsd.edu/wiki/MoBILAB), an open source, cross platform toolbox running on MATLAB (The Mathworks, Inc.) that supports analysis and visualization of any mixture of synchronously recorded brain, behavioral, and environmental time series plus time-marked event stream data. MoBILAB can serve as a pre-processing environment for adding behavioral and other event markers to EEG data for further processing, and/or as a development platform for expanded analysis of simultaneously recorded data streams.

Effect of a low‐flatulogenic diet in patients with flatulence and functional digestive symptoms

Diets rich in fermentable residues increase intestinal gas production. Our aim was to demonstrate the potential effects of diet on gas-related symptoms. The effect of a low-flatulogenic test diet (restricted to foodstuffs low in fermentable residues; n=15) was compared to that of a balanced control diet (Mediterranean type; n=15) in 30 patients complaining of flatulence and other abdominal symptoms using a randomized parallel design. The following outcomes were measured daily: number of anal gas evacuations by an event marker, severity of gas-related symptoms by 0-10 scales, and sensation of digestive comfort by a -5 (unpleasant) to +5 (pleasant) scale. Measurements were taken pretreatment for 3days on their habitual diet and for 7days during the treatment phase. No pretreatment differences were detected between patients allocated to the control or test diets. The test diet significantly reduced the number of gas evacuations (by 54±10%; p=0.002 vs basal diet) whereas the control diet had a lesser effect (reduction by 28±9%; p=0.059 vs basal diet; p=0.089 vs test diet). Compared to the control diet, the test diet significantly reduced flatulence (by 48±7% vs 27±8%, respectively; p=0.018), abdominal distension (by 48±4% vs 22±12%, respectively; p=0.038), and enhanced digestive well-being (by 149±18% vs 58±22%, respectively; p=0.006). In patients with gas-related symptoms, a low-flatulogenic diet produces immediate beneficial effects with digestive, cognitive, and emotive dimensions. The number of gas evacuations is an objective biological marker of response to dietary treatment.

Validation of a sternal skin conductance criterion for measuring hot flashes in breast cancer patients

This study aimed to establish the sternal skin conductance level (SCL) increase that would optimally detect hot flashes among breast cancer patients. Fifty-six women who had completed a similar treatment protocol for a first diagnosis of breast cancer within the previous 3 months wore an ambulatory sternal skin conductance device for one home-based daytime recording of hot flashes. A total of 199 hot flashes were reported by the participants using the event marker. A 2-μS (μmho) SCL increase within a 30-second period, the criterion typically used, had a sensitivity of only 32% and a specificity of 97%. Comparatively, the alternative criterion proposed here, a 1.2-μmho SCL increase, yielded a sensitivity of 61% and a specificity of 90%. This study provides evidence that a lower SCL criterion should be used to better detect objectively recorded hot flashes among breast cancer patients. Further work is needed to validate the proposed criterion among this population.

Miniature ambulatory skin conductance monitor and algorithm for investigating hot flash events

A skin conductance monitoring system was developed and shown to reliably acquire and record hot flash events in both supervised laboratory and unsupervised ambulatory conditions. The 7.2 × 3.8 × 1.2 cm3 monitor consists of a disposable adhesive patch supporting two hydrogel electrodes and a reusable, miniaturized, enclosed electronic circuit board that snaps onto the electrodes. The monitor measures and records the skin conductance for seven days without external wires or telemetry and has an event marker that the subject can press whenever a hot flash is experienced. The accuracy of the system was demonstrated by comparing the number of hot flashes detected by algorithms developed during this research with the number identified by experts in hot flash studies. Three methods of detecting hot flash events were evaluated, but only two were fully developed. The two that were developed were an artificial neural network and a matched filter technique with multiple kernels implemented as a sliding form of the Pearson product-moment correlation coefficient. Both algorithms were trained on a ‘development’ cohort of 17 women and then validated using a second similar ‘validation’ cohort of 20. All subjects were between the ages of 40 and 60 and self-reported ten or more hot flashes per day over a three day period. The matched filter was the most accurate with a mean sensitivity of 0.92 and a mean specificity of 0.90 using the data from the development cohort and a mean sensitivity of 0.92 and a mean specificity of 0.87 using the data from the validation cohort. The matched filter was the method implemented in our processing software.

Multiplexed, data structure-based enriched physiological event marker system

Event Abstract Back to Event Multiplexed, data structure-based enriched physiological event marker system Derek Rollend1* and Marcos Osorno1 1 JHU/APL, United States "As has been stressed by international scientific standards committees, event markers allow for the alignment of experiment events with their associated physiological data in the post-processing phase of an experiment and are crucial for providing context in recorded measurements [1]. Current physiological data file formats only afford rudimentary event encoding schemes, including hexadecimal event codes with a separate user-defined lookup table file, and time-stamped experiment annotations [2, 3]. The latter requires synchronizing the data acquisition system and annotation-generating software. It becomes desirable then to simultaneously generate and record both experiment events and metadata (annotations) from multiple subjects in a unified form that is compatible with existing physiological data file formats. To meet these goals, an alternative event marker method was developed. A data structure, loosely based on standard transmission protocol structures, was used in order to contain both an event description and a payload of associated event metadata or experiment behavioral data. This event marker system has been successfully demonstrated in an ongoing psychophysiological experiment where the total expected number of participants is between 100-200 volunteers. To alleviate the bookkeeping burden during the analysis phase of the experiment, participant identification, experiment identification, participant roles, and behavioral metadata have been packaged within event markers. This has enabled 1) human-readable, meaningful event descriptions to be overlaid on recorded EEG, ECG, EOG, and GSR signals, 2) quantifiable behavioral data for post-processing and machine learning based analysis, and 3) backup participant meta-data contained within the data file for information consistency checking during analysis. 1. Nuwer, Marc R. et al. "FCN Standards IFCN standards for digital recording of clinical EEG." Electroencephalography and Clinical Neurophysiology, Volume 106, Issue 3, 1998, Pages 259-261, ISSN 0168-5597. 2. Velde, Maarten van de et al. "Digital archival and exchange of events in a simple format for polygraphic recordings with application in event related potential studies." ISSN 0013-4694, http://dx.doi.org/10.1016/S0013-4694 (98)00029-7. 3. Kemp, B. Olivan, J. "European data format 'plus' (EDF+)." ISSN 1388-2457, 10.1016/S1388-2457(03)00123-8." Keywords: Electrophysiology, method development, event marker system, Software Development, computational neuroscience Conference: 5th INCF Congress of Neuroinformatics, Munich, Germany, 10 Sep - 12 Sep, 2012. Presentation Type: Poster Topic: Neuroinformatics Citation: Rollend D and Osorno M (2014). Multiplexed, data structure-based enriched physiological event marker system. Front. Neuroinform. Conference Abstract: 5th INCF Congress of Neuroinformatics. doi: 10.3389/conf.fninf.2014.08.00096 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 21 Mar 2013; Published Online: 27 Feb 2014. * Correspondence: Dr. Derek Rollend, JHU/APL, Laurel, United States, derek.rollend@jhuapl.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Derek Rollend Marcos Osorno Google Derek Rollend Marcos Osorno Google Scholar Derek Rollend Marcos Osorno PubMed Derek Rollend Marcos Osorno Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Progress in compliance research and intervention: a commentary

Progress in compliance research and intervention: a commentary

Medication Adherence Assessment

BackgroundThis open-label single-arm exploratory study evaluated the accuracy of the Ingestible Sensor System (ISS), a novel technology for directly assessing the ingestion of oral medications and treatment adherence.MethodsISS consists of an ingestible event marker (IEM), a microsensor that becomes activated in gastric fluid, and an adhesive personal monitor (APM) that detects IEM activation. In this study, the IEM was combined to enteric-coated mycophenolate sodium (ECMPS). Twenty stable adult kidney transplants received IEM-ECMPS for a mean of 9.2 weeks totaling 1227 cumulative days.ResultsEight patients prematurely discontinued treatment due to ECMPS gastrointestinal symptoms (n=2), skin intolerance to APM (n=2), and insufficient system usability (n=4). Rash or erythema due to APM was reported in 7 (37%) patients, all during the first month of use. No serious or severe adverse events and no rejection episode were reported. IEM detection accuracy was 100% over 34 directly observed ingestions; Taking Adherence was 99.4% over a total of 2824 prescribed IEM-ECMPS ingestions. ISS could detect accurately the ingestion of two IEM-ECMPS capsules taken at the same time (detection rate of 99.3%, n=2376).ConclusionsISS is a promising new technology that provides highly reliable measurements of intake and timing of intake of drugs that are combined with the IEM.