An EEG coherence-based analysis approach for investigating response conflict processes in 7 and 9-year old children

Understanding the development of the brain's neural networks can reveal critical insights into the cognitive changes that occur from infancy to late childhood. Behavioural metrics including: task accuracy, stimuli recognition, and reaction time show dramatic changes over childhood. In this study we investigated response control using the Erikson Flanker task. In a dataset of 45 EEG recordings, we calculated spectral coherence to measure connectivity between all possible electrode pairs. Coherence measures were performed on two different trial conditions -congruent (where there is no response conflict) and incongruent (where response conflict is induced). The increase in incongruent coherence compared to the congruent was investigated for each electrode pair over 45 healthy subjects aged seven years. The same calculation was then performed on the same group of subjects two years later when they were aged nine years. The results revealed that at age seven years, increased coherence was detected in the left prefrontal to right and left parieto-occipital - i.e. an anatomical region located between the parietal and occipital lobes - within theta band. No increase was found for the older group-at age nine years- which may indicate cognitive development in conflict processing mechanism.

Abstract OT3-04-02: The DORA trial: A non-comparator randomised phase II multi-center maintenance study of olaparib alone or olaparib in combination with durvalumab in platinum treated advanced triple negative breast cancer (TNBC)

Background: Recent data from the OlympiaD study revealed an improvement in response rate and progression-free survival (PFS) with the PARP inhibitor (PARPi) olaparib vs. standard of care chemotherapy in patients with metastatic breast cancer who harbor germline BRCA (gBRCA) mutations. Maintenance PARPi has improved median PFS in relapsed ovarian cancer regardless of gBRCA mutation status or HRD status. The similarities between the molecular aberration profiles of high-grade serous ovarian cancer and TNBC invites exploration of maintenance PARPi in mTNBC. Furthermore, because durable responses have been reported in subsets of patients with metastatic TNBC (mTNBC) with checkpoint blockade and because high mutational load is associated with both gBRCA and TNBC, these patients may be particularly susceptible to immunotherapy with PARPi. Thus, we hypothesize that olaparib either alone or in combination with the PD-L1 inhibitor durvalumab will be active in TNBC subjects who have responded to platinum-based chemotherapy.

Trial design: DORA is a non-comparator randomized, international, multicenter phase II study designed to explore the efficacy of olaparib with or without durvalumab as maintenance therapy in platinum-treated mTNBC. Subjects will be enrolled following four cycles of treatment with a platinum-based (cisplatin or carboplatin) chemotherapy as single agent or combination therapy. Subjects deriving clinical benefit (CR / PR / SD) with platinum-based therapy as determined by the treating physician will be eligible and randomized in a 1:1 ratio. Patients in arm 1 will receive olaparib orally 300mg BID continuously and in arm 2 will receive olaparib orally 300mg BID continuously in combination with durvalumab 1500mg IV every 4 wks. Tumor responses will be assessed every 8 wks.

Eligibility criteria: Subjects with mTNBC who are receiving platinum-based chemotherapy and who have had no more than 2 lines of chemotherapy in the metastatic or advanced setting, with one of those being a platinum, will be included in this trial. Eligible patients must have been assessed by their treating physicians to have derived clinical benefit with platinum based therapy. Archival tissue or fresh biopsy samples are mandated for biomarker analyses.

Aims:The primary endpoint is PFS; the key secondary endpoint is overall survival.

Statistical methods: The sample size is calculated based upon data derived from contemporary trials of chemotherapy in mTNBC. In both arms of the study, it is proposed to test a null hypothesis of a median PFS of 2 months against an alternative hypothesis of a median PFS of 4 months; there is no intention to make a formal statistical comparison between the two treatment arms. To test this hypothesis, assuming an exponential PFS distribution, use of an exponential MLE test, a two-sided significance level of 5% and a power of 90%, 25 subjects are required per arm.

Target accrual: To allow for a drop-out rate of approximately 20%, the sample size per arm will be inflated to 30 subjects. We plan to enroll approximately 60 subjects with mTNBC from 6 centers.

ClinicalTrials.gov Identifier: NCT03167619

Citation Format: Dent R, Tan T, Kim S-B, Traina T, McArthur H, Im Y-H, Creel T, Blackwell K. The DORA trial: A non-comparator randomised phase II multi-center maintenance study of olaparib alone or olaparib in combination with durvalumab in platinum treated advanced triple negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-04-02.

Venous thromboembolic prophylaxis after simultaneous bilateral total knee arthroplasty: aspirin versus warfarin

Aims

The aims of this study were to compare the efficacy of two agents, aspirin and warfarin, for the prevention of venous thromboembolism (VTE) after simultaneous bilateral total knee arthroplasty (SBTKA), and to elucidate the risk of VTE conferred by this procedure compared with unilateral TKA (UTKA).

Patients and Methods

A retrospective, multi-institutional study was conducted on 18 951 patients, 3685 who underwent SBTKA and 15 266 who underwent UTKA, using aspirin or warfarin as VTE prophylaxis. Each patient was assigned an individualised baseline VTE risk score based on a system using the Nationwide Inpatient Sample. Symptomatic VTE, including pulmonary embolism (PE) and deep vein thrombosis (DVT), were identified in the first 90 days post-operatively. Statistical analyses were performed with logistic regression accounting for baseline VTE risk.

Results

The adjusted incidence of PE following SBTKA was 1.0% (95% confidence interval (CI) 0.86 to 1.2) with aspirin and 2.2% (95% CI 2.0 to 2.4) with warfarin. Similarly, the adjusted incidence of VTE following SBTKA was 1.6% (95% CI 1.1 to 2.3) with aspirin and 2.5% (95% CI 1.9 to 3.3) with warfarin. The risk of PE and VTE were reduced by 66% (odds ratio (OR) 0.44, 95% CI 0.25 to 0.78) and 38% (OR 0.62, 95% CI 0.38 to 1.0), respectively, using aspirin. In addition, the risk of PE was 204% higher for patients undergoing SBTKA relative to those undergoing UTKA. For each ten-point increase in baseline VTE risk, the risk of PE increased by 25.5% for patients undergoing SBTKA compared with 10.5% for those undergoing UTKA. Patients with a history of myocardial infarction or peripheral vascular disease had the greatest increase in risk from undergoing SBTKA instead of UTKA.

Conclusion

Aspirin is more effective than warfarin for the prevention of VTE following SBTKA, and serves as the more appropriate agent for VTE prophylaxis for patients in all risk categories. Furthermore, patients undergoing SBTKA are at a substantially increased risk of VTE, even more so for those with significant underlying risk factors. Patients should be informed about the risks associated with undergoing SBTKA.

Cite this article: Bone Joint J 2018;100-B(1 Supple A):68–75.

Real-Time Observation of Phonon-Mediated σ-π Interband Scattering in MgB_{2}

In systems having an anisotropic electronic structure, such as the layered materials graphite, graphene, and cuprates, impulsive light excitation can coherently stimulate specific bosonic modes, with exotic consequences for the emergent electronic properties. Here we show that the population of E_{2g} phonons in the multiband superconductor MgB_{2} can be selectively enhanced by femtosecond laser pulses, leading to a transient control of the number of carriers in the σ-electronic subsystem. The nonequilibrium evolution of the material optical constants is followed in the spectral region sensitive to both the a- and c-axis plasma frequencies and modeled theoretically, revealing the details of the σ-π interband scattering mechanism in MgB_{2}.

A diaper-embedded disposable nitrite sensor with integrated on-board urine-activated battery for UTI screening

This paper reports a low-cost solution to the early detection of urinary nitrite, a common surrogate for urinary tract infection (UTI). We present a facile method to fabricate a disposable and flexible colorimetric [1] nitrite sensor and its urine-activated power source [2] on a hydrophobic (wax) paper through laser-assisted patterning and lamination. Such device, integrated with interface circuitry and a Bluetooth low energy (BLE) module can be embedded onto a diaper, and transmit semi-quantitative UTI monitoring information in a point-of-care and autonomous fashion. The proposed nitrite sensing platform achieves a sensitivity of 1.35 ms/(mg/L) and a detection limit of 4 mg/L.

Response conflict processes' classification in 7 and 9 year old children using EEG brain connectivity measures

Investigating cognitive development of children poses interesting challenges pertaining to emergence of children's' ability to think and understand. Psychological tasks that involve conflict, like the Flanker task, are widely used to understand development of response conflict processes. In this study, EEG signals were used to examine the coherence and imaginary part of coherency within the delta, theta, alpha and beta bands across different conditions of the Flanker task. Longitudinal data were collected from a group of typically developing children at ages of seven and nine. We found that the imaginary part of coherency was more helpful in distinguishing between stimuli - alpha and beta bands resulted in 90.90% classification rate in seven year old children. The beta and theta bands were found to be more effective for stimuli classification in nine year old children - more than 84.09% classification accuracy was achieved.