Plasma electron acceleration driven by a long-wave-infrared laser

Laser-driven plasma accelerators provide tabletop sources of relativistic electron bunches and femtosecond x-ray pulses, but usually require petawatt-class solid-state-laser pulses of wavelength λL ~ 1 μm. Longer-λL lasers can potentially accelerate higher-quality bunches, since they require less power to drive larger wakes in less dense plasma. Here, we report on a self-injecting plasma accelerator driven by a long-wave-infrared laser: a chirped-pulse-amplified CO2 laser (λL ≈ 10 μm). Through optical scattering experiments, we observed wakes that 4-ps CO2 pulses with <  1/2 terawatt (TW) peak power drove in hydrogen plasma of electron density down to 4 × 1017 cm-3 (1/100 atmospheric density) via a self-modulation (SM) instability. Shorter, more powerful CO2 pulses drove wakes in plasma down to 3 × 1016 cm-3 that captured and accelerated plasma electrons to relativistic energy. Collimated quasi-monoenergetic features in the electron output marked the onset of a transition from SM to bubble-regime acceleration, portending future higher-quality accelerators driven by yet shorter, more powerful pulses.

Safety of fertility-sparing surgery in young women with stage I endometrioid epithelial and mucinous ovarian cancer: A population-based analysis

INTRODUCTION

The aim of this study was to assess the safety of fertility-sparing surgery (FSS) in stage I endometrioid epithelial cancer (EEOC) and mucinous ovarian cancer (MOC).

METHODS

A retrospective case‒controlled study was conducted using the Surveillance, Epidemiology, and End Results (SEER) database, focusing on stage I EEOC and MOC between 2000 and 2016. The effects of FSS on overall survival (OS) were compared using log-rank tests. Univariate and multivariate Cox analyses were performed to control for confounders.

RESULTS

The study identified 970 patients with FIGO stage I EEOC and 810 with stage I MOC. Of these patients, 116 (12.0%) EEOC and 268 (33.1%) MOC patients underwent fertility-sparing surgery. The results showed that patients with G3 EEOC had a worse 5-year OS than patients with G1 EEOC (96.1% vs. 90.1%, p = 0.020). IC stage MOC patients had a worse prognosis than IA and IB stage patients (94.9% vs. 88.7%, p = 0.001). FSS did not significantly affect the 5-year OS of patients with EEOC (94.8% vs. 95.4%, p = 0.687) or MOC (95.9% vs. 92.3%, p = 0.071). Further subgroup analysis according to tumor stage and histological grade did not show a worse OS with FSS in stage I EEOC or MOC patients, even with high-risk types such as G3 histology and IC phase. In a multivariable analysis, the application of FSS was not associated with inferior OS in EEOC or MOC.

CONCLUSIONS

FSS for patients with stage I EEOC or MOC does not lead to worse outcomes than radical surgery, making it a viable option for young patients with early-stage disease wishing to preserve fertility.

Pembrolizumab monotherapy versus chemotherapy in platinum-pretreated, recurrent or metastatic nasopharyngeal cancer (KEYNOTE-122): an open-label, randomized, phase III trial

BACKGROUND

Pembrolizumab previously demonstrated robust antitumor activity and manageable safety in a phase Ib study of patients with heavily pretreated, programmed death ligand 1 (PD-L1)-positive, recurrent or metastatic nasopharyngeal carcinoma (NPC). The phase III KEYNOTE-122 study was conducted to further evaluate pembrolizumab versus chemotherapy in patients with platinum-pretreated, recurrent and/or metastatic NPC. Final analysis results are presented.

PATIENTS AND METHODS

KEYNOTE-122 was an open-label, randomized study conducted at 29 sites, globally. Participants with platinum-pretreated recurrent and/or metastatic NPC were randomly assigned (1 : 1) to pembrolizumab or chemotherapy with capecitabine, gemcitabine, or docetaxel. Randomization was stratified by liver metastasis (present versus absent). The primary endpoint was overall survival (OS), analyzed in the intention-to-treat population using the stratified log-rank test (superiority threshold, one-sided P = 0.0187). Safety was assessed in the as-treated population.

RESULTS

Between 5 May 2016 and 28 May 2018, 233 participants were randomly assigned to treatment (pembrolizumab, n = 117; chemotherapy, n = 116); Most participants (86.7%) received study treatment in the second-line or later setting. Median time from randomization to data cut-off (30 November 2020) was 45.1 months (interquartile range, 39.0-48.8 months). Median OS was 17.2 months [95% confidence interval (CI) 11.7-22.9 months] with pembrolizumab and 15.3 months (95% CI 10.9-18.1 months) with chemotherapy [hazard ratio, 0.90 (95% CI 0.67-1.19; P = 0.2262)]. Grade 3-5 treatment-related adverse events occurred in 12 of 116 participants (10.3%) with pembrolizumab and 49 of 112 participants (43.8%) with chemotherapy. Three treatment-related deaths occurred: 1 participant (0.9%) with pembrolizumab (pneumonitis) and 2 (1.8%) with chemotherapy (pneumonia, intracranial hemorrhage).

CONCLUSION

Pembrolizumab did not significantly improve OS compared with chemotherapy in participants with platinum-pretreated recurrent and/or metastatic NPC but did have manageable safety and a lower incidence of treatment-related adverse events.

Genomic and expressional dynamics of ovarian cancer cell lines in PARPi treatment revealed mechanisms of acquired resistance

BACKGROUND

Patients with epithelial ovarian cancer (EOC) can benefit from poly- (ADP ribose) polymerase inhibitors (PARPi) therapy. However, PARPi resistance has become a challenge in clinical practice, and its mechanism requires further exploration.

METHODS

We established three PARPi-resistant cell strains following olaparib exposure. CCK-8, clonogenic survival, transwell, wound healing, cell cycle, RT-qPCR and western blot assays were performed to explore the functional phenotype of the resistant cells. Whole-exome sequencing and RNA-sequencing were performed to identify the altered genes. Stable knockdown and overexpression were used to investigate the role of EP300, an upstream regulator of E-cadherin and epithelial-mesenchymal transition (EMT), in cell lines. We further validated the finding in clinical ovarian cancer samples by immunohistochemistry.

RESULTS

We combined public datasets to obtain an integrated PARPi sensitivity profile in EOC cells, which indicated that primary PARPi resistance could not be fully explained by mutations in BRCA1/2 or homologous recombination deficiency related genes. Genomic and transcriptome analyses revealed distinct mechanisms between primary and acquired resistance. Long-term PARPi treatment induced accumulation of de novo single nucleotide variants (SNV), and the complete frame-shift deletion of PARP1 was detected in the A2780 resistant strain. Additionally, the depressed histone acetyltransferase of EP300 could cause resistant phenotype through activated EMT process in vitro, and associated with PARPi-resistance in EOC patients.

CONCLUSION

Long-term PARPi treatment led to evolutionary genomic and transcriptional alterations that were associated with acquired resistance, among which depressed EP300 partly contributed to the resistant phenotype.

Neutrophil-Lymphocyte Ratio and Absolute Lymphocyte Count as Prognostic Markers in Patients Treated with Curative-intent Radiotherapy for Non-small Cell Lung Cancer

AIMS

The neutrophil-lymphocyte ratio (NLR) and the absolute lymphocyte count (ALC) have been proposed as prognostic markers in non-small cell lung cancer (NSCLC). The objective of this study was to examine the association of NLR/ALC before and after curative-intent radiotherapy for NSCLC on disease recurrence and overall survival.

MATERIALS AND METHODS

A retrospective study of consecutive patients who underwent curative-intent radiotherapy for NSCLC across nine sites in the UK from 1 October 2014 to 1 October 2016. A multivariate analysis was carried out to assess the ability of pre-treatment NLR/ALC, post-treatment NLR/ALC and change in NLR/ALC, adjusted for confounding factors using the Cox proportional hazards model, to predict disease recurrence and overall survival within 2 years of treatment.

RESULTS

In total, 425 patients were identified with complete blood parameter values. None of the NLR/ALC parameters were independent predictors of disease recurrence. Higher pre-NLR, post-NLR and change in NLR plus lower post-ALC were all independent predictors of worse survival. Receiver operator curve analysis found a pre-NLR > 2.5 (odds ratio 1.71, 95% confidence interval 1.06-2.79, P < 0.05), a post-NLR > 5.5 (odds ratio 2.36, 95% confidence interval 1.49-3.76, P < 0.001), a change in NLR >3.6 (odds ratio 2.41, 95% confidence interval 1.5-3.91, P < 0.001) and a post-ALC < 0.8 (odds ratio 2.86, 95% confidence interval 1.76-4.69, P < 0.001) optimally predicted poor overall survival on both univariate and multivariate analysis when adjusted for confounding factors. Median overall survival for the high-versus low-risk groups were: pre-NLR 770 versus 1009 days (P = 0.34), post-NLR 596 versus 1287 days (P ≤ 0.001), change in NLR 553 versus 1214 days (P ≤ 0.001) and post-ALC 594 versus 1287 days (P ≤ 0.001).

CONCLUSION

NLR and ALC, surrogate markers for systemic inflammation, have prognostic value in NSCLC patients treated with curative-intent radiotherapy. These simple and readily available parameters may have a future role in risk stratification post-treatment to inform the intensity of surveillance protocols.

Embracing informed learner self-assessment during debriefing: the art of plus-delta

The healthcare simulation field has no shortage of debriefing options. Some demand considerable skill which serves as a barrier to more widespread implementation. The plus-delta approach to debriefing offers the advantages of conceptual simplicity and ease of implementation. Importantly, plus-delta promotes learners' capacity for a self-assessment, a skill vital for safe clinical practice and yet a notorious deficiency in professional practice. The plus-delta approach confers the benefits of promoting uptake of debriefing in time-limited settings by educators with both fundamental but also advanced skills, and enhancing essential capacity for critical self-assessment informed by objective performance feedback. In this paper, we describe the role of plus-delta in debriefing, provide guidance for incorporating informed learner self-assessment into debriefings, and highlight four opportunities for improving the art of the plus delta: (a) exploring the big picture vs. specific performance issues, (b) choosing between single vs. double-barreled questions, (c) unpacking positive performance, and (d) managing perception mismatches.

Predicting the Risk of Disease Recurrence and Death Following Curative-intent Radiotherapy for Non-small Cell Lung Cancer: The Development and Validation of Two Scoring Systems From a Large Multicentre UK Cohort

AIMS

There is a paucity of evidence on which to produce recommendations on neither the clinical nor the imaging follow-up of lung cancer patients after curative-intent radiotherapy. In the 2019 National Institute for Health and Care Excellence lung cancer guidelines, further research into risk-stratification models to inform follow-up protocols was recommended.

MATERIALS AND METHODS

A retrospective study of consecutive patients undergoing curative-intent radiotherapy for non-small cell lung cancer from 1 October 2014 to 1 October 2016 across nine UK trusts was carried out. Twenty-two demographic, clinical and treatment-related variables were collected and multivariable logistic regression was used to develop and validate two risk-stratification models to determine the risk of disease recurrence and death.

RESULTS

In total, 898 patients were included in the study. The mean age was 72 years, 63% (562/898) had a good performance status (0-1) and 43% (388/898), 15% (134/898) and 42% (376/898) were clinical stage I, II and III, respectively. Thirty-six per cent (322/898) suffered disease recurrence and 41% (369/898) died in the first 2 years after radiotherapy. The ASSENT score (age, performance status, smoking status, staging endobronchial ultrasound, N-stage, T-stage) was developed, which stratifies the risk for disease recurrence within 2 years, with an area under the receiver operating characteristic curve (AUROC) for the total score of 0.712 (0.671-0.753) and 0.72 (0.65-0.789) in the derivation and validation sets, respectively. The STEPS score (sex, performance status, staging endobronchial ultrasound, T-stage, N-stage) was developed, which stratifies the risk of death within 2 years, with an AUROC for the total score of 0.625 (0.581-0.669) and 0.607 (0.53-0.684) in the derivation and validation sets, respectively.

CONCLUSIONS

These validated risk-stratification models could be used to inform follow-up protocols after curative-intent radiotherapy for lung cancer. The modest performance highlights the need for more advanced risk prediction tools.

RV Pacing Percentage

Introduction

Chronic right ventricular pacing (RVP) has been associated with dyssynchrony, leading to increased mortality. However, there have been discrepancies in previous reports in the effect of RVP levels.

Objective

To sub-stratify mortality risk by age for different RVP level groups within a large real-world ICD cohort.

Methods

Optum® de-identified electronic health records were linked to the Medtronic Carelink data to identify dual chamber ICD recipients (2007–2017). RVP level was based on median daily pacing during the first 90 days post-implant and categorized either into groups with a cutoff of 40%, or with groups of 0–9%, 10–19%, 20–29%, 30–39%, 40–49%, and 50–100%. The endpoint was death more than 90 days post-implant. Kaplan-Meier survival curves, log-rank tests, and Cox regression were used to analyze the relationship between RVP and risk of death.

Results

Among 14,832 ICD patients (median age 67; 74.0% male), there were 2,602 deaths within 10 years after implant. In unadjusted comparisons, high RVP (&gt;40%) increased the risk of death relative to low RVP (≤40%) (p&lt;0.001). This effect remained significant in older cohort (≥67 years old at implant) (p&lt;0.001), but not in younger cohort (&lt;67 years old) (p=0.955) (Figure). After controlling for age, gender, pacing mode, MI, SCA, HF hospitalization, diabetes, and renal dysfunction, similar or increased risk was associated with higher pacing groups relative to the 0–9% pacing group in the older cohort, but not in the younger cohort.

Conclusions

Our data from a large contemporaneous real-world source suggests that older age or characteristics associated with age make patients more sensitive to chronic RVP effects. These results help reconcile differences observed in prior studies.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Medtronic, Inc.

Clinical outcomes from out-of-hospital cardiac arrest in low-resource settings - A scoping review

AIM OF THE SCOPING REVIEW

Scientific recommendations on resuscitation are typically formulated from the perspective of an ideal resource environment, with little consideration of applicability in lower-income countries. We aimed to determine clinical outcomes from out-of-hospital cardiac arrest (OHCA) in low-resource countries, to identify shortcomings related to resuscitation in these areas and possible solutions, and to suggest future research priorities.

DATA SOURCES

This scoping review was part of the continuous evidence evaluation process of the International Liaison Committee on Resuscitation (ILCOR), and was performed following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews. We identified low-resource countries as countries with a low- or middle gross national income per capita (World Bank data). We performed a literature search on outcomes after OHCA in these countries, and we extracted data on the outcome. We applied descriptive statistics and conducted a post-hoc correlation analysis of cohort size and ROSC rates.

RESULTS

We defined 24 eligible studies originating from middle-income countries, but none from low-income regions, suggesting a reporting bias. The number of reported patients in these studies ranged from 54 to 3214. Utstein-style reporting was rarely used. Return of spontaneous circulation varied from 0% to 62%. Fifteen studies reported on survival to hospital discharge (between 1.0 and 16.7%) or favourable neurological outcome (between 1.0 and 9.3%). An inverse correlation was found for study cohort size and the rate of return of spontaneous circulation (ρ = -0.48, p = 0.034).

CONCLUSION

Studies of OHCA outcomes in low-resource countries are heterogeneous and may be compromised by reporting bias. Minimum cardiopulmonary resuscitation standards for low-resource settings should be developed collaboratively involving local experts, respecting culture and context while balancing competing health priorities.

The prokaryotic expression, polyclonal antibody preparation, and subcellular localization of the transmembrane protein NS2A of the duck Tembusu virus

Duck Tembusu virus (DTMUV) is a single-stranded, positive-sense RNA arbovirus, belonging to the genus Flavivirus, the family Flaviviridae. As a transmembrane protein, non-structural protein 2A (NS2A) plays an important role in virion assembly, replication complex and antagonizing host immune response. Since NS2A protein contains many hydrophobic amino acids, it is hard to gain the full-length protein of NS2A for prokaryotic expression. Therefore, to make a deep study, prokaryotic expression and polyclonal antibody preparation of truncated DTMUV NS2A was performed. The truncated NS2A gene (178-450 bp) was obtained, and sub-cloned into the prokaryotic vector pGEX-4T-1 (pGEX-4T-1-NS2A178-450bp). Subsequently, the recombinant GST-NS2A60-150aa protein was successfully expressed in E. coli BL21 (DE3) with the induction by 0.3 mmol/l isopropyl β-D-thiogalactoside (IPTG) for 6 h at 37°C. The GST-NS2A60-150aa protein was extracted from the gel. The BALB/c mice were immunized with the purified recombinant NS2A protein to prepare polyclonal antibodies against the truncated NS2A protein. The titer of the polyclonal antibodies, determined by ELISA analysis, was 1:128,000. The specificity of the polyclonal antibodies (mPAb-DTMUV-NS2A60-150aa) were verified by Western blot analysis. Furthermore, the indirect immunofluorescence (IFA) was performed to explore the subcellular localization of NS2A. NS2A protein was, in the transfected cells, located mainly around nucleus in the endoplasmatic reticulum. Taken together, our study provided a useful tool for the further exploration of the biological functions and molecular mechanism of DTMUV NS2A. Keywords: duck Tembusu virus; non-structural protein 2A; prokaryotic expression; polyclonal antibodies; subcellular location.

Survival Analysis of Lymph Node Resection in Ovarian Cancer: A Population-Based Study

Objective: This study aimed at comprehensively investigating the survival impact of lymphadenectomy during primary surgery in ovarian cancer. Methods: Based on the surveillance, epidemiology, and end results registry (SEER) database, we included ovarian cancer patients with detailed information between 2010 and 2016. Cox regression was performed to select prognostic factors. We conducted propensity score-weighted survival analysis to balance baseline variables, and series of stratified analyses to control main confounding factors. Results: A total of 8,652 patients were ultimately identified. Among 4,360 patients with advanced disease, lymphadenectomy did not show significant survival benefit in general (median overall survival 44 months in non-lymphadenectomy vs. 49 months in lymphadenectomy group, P = 0.055). In subgroup analysis on patients received optimal debulking, lymphadenectomy did not significantly benefit the survival outcome (median overall survival 51, 47, 60, and 58 months in the non-lymphadenectomy, 1-9 lymph nodes, 10-19 lymph nodes, ≥20 lymph nodes groups, respectively, P = 0.287). Consistent results were observed in further stratification analyses. In optimal debulking subgroup, lymph node metastasis indicated worse survival. However, when limited the number of removed lymph nodes to more than 15, there was a marginal statistical difference in overall survival (P = 0.0498) while no significant difference presented in cause-specific survival (P = 0.129) between non-lymphadenectomy, pathological negative lymph node group and positive lymph node group. And the regions of lymph metastasis were also not significantly associate with survival (P = 0.123). Among 3,266 (75%) patients with apparent early-stage disease received lymphadenectomy, 7.75% of whom were reported isolated lymph nodes metastasis and have a poorer survival (P < 0.05). Conclusions: In primary debulking for patients with advanced ovarian cancer, lymphadenectomy was not associated with more favorable outcomes when compared to no lymphadenectomy. The value of lymphadenectomy lies more in staging for apparent early disease rather than therapeutic benefit.

Color, composition, and thermal environment of Kuiper Belt object (486958) Arrokoth

The outer Solar System object (486958) Arrokoth (provisional designation 2014 MU₆₉) has been largely undisturbed since its formation. We studied its surface composition using data collected by the New Horizons spacecraft. Methanol ice is present along with organic material, which may have formed through irradiation of simple molecules. Water ice was not detected. This composition indicates hydrogenation of carbon monoxide-rich ice and/or energetic processing of methane condensed on water ice grains in the cold, outer edge of the early Solar System. There are only small regional variations in color and spectra across the surface, which suggests that Arrokoth formed from a homogeneous or well-mixed reservoir of solids. Microwave thermal emission from the winter night side is consistent with a mean brightness temperature of 29 ± 5 kelvin.

Central Sensitization-Related Changes in Brain Function Activity in a Rat Endometriosis-Associated Pain Model

Background

Pain sensitization processing in the central nervous system may be related to endometriosis-associated pain in patients. The purpose of this study was to understand the alterations in the abnormal pain response in central brain areas and explore the central sensitization mechanism of endometriosis-associated pain.

Methods

An endometriosis model was established in 40 Sprague-Dawley rats, and the rats underwent pain model assessment through behavioral tests. Twenty Sprague-Dawley rats underwent a sham operation as the control group. Thirteen pain rats and 8 control rats received Rs-fMRI examination to explore the brain functional activity areas, and the regional homogeneity (ReHo) method was used to analyze relevant functional signals among the whole brain. The states of neurons and expression of TRPV1 and NMDRA located in the abnormal ReHo signal brain regions were observed using Nissl staining, qRT-PCR and immunohistochemistry.

Results

The rats were divided into a pain group and a control group based on the different syndromes and behavioral assessments. We detected significant enhancement of ReHo signals in the anterior cingulate cortex, hippocampus, and thalamus and a reduction in the ReHo values in the basomedial amygdaloid nucleus (BM) and primary motor cortex (M1) in the pain rat group via Rs-fMRI examination. The number of Nissl bodies and apoptotic neurons was increased; moreover, the volume of neurons increased compensatorily in the cingulate cortex, thalamus and hippocampus in the pain group. TRPV1 and NMDRA were overexpressed in apoptotic neurons in the higher ReHo value brain regions in the endometriosis pain group.

Conclusion

These findings suggest that in rats with endometriosis-associated pain, ReHo signal enhancement was observed in the cingulate cortex, thalamus and hippocampus, which may be due to the increase in the number of apoptotic neurons or the compensatory increase in the volume of overactive neurons.

P1445 DORv and window: a case of an uncorrected double outlet right ventricle with d-transposition of great arteries with concomitant aortopulmonary window in a 31-year-old female

Funding Acknowledgements

none

Double outlet right ventricle (DORV) is a rare type of ventriculo-arterial connection occurring in about 1-3% of congenital heart defects. Moreover, transposition of the great arteries, wherein the aorta is anterior and to the right of the pulmonary artery (D-TGA), accounts for only 26% of cases of DORV. An aortopulmonary window, on the other hand, represents approximately only 0.2% of all congenital cardiac lesions. A case of DORV with D-TGA and pulmonary stenosis with a concomitant aortopulmonary window has never been reported, particularly in an adult in the third decade of life and without any history of surgical repair.

We present the case of a 31-year-old female who had sought consult for left-sided weakness. On physical examination, a grade IV/VI systolic murmur was heard at the left anterior chest and cyanosis of the digits of the upper and lower extremities were noted. Transthoracic echocardiogram revealed a non-restrictive ventricular septal defect (VSD) and segmental approach showed atrial and visceral situs solitus, levocardia, and atrioventricular concordance. However, there was ventriculoarterial discordance with fusiform aneurysmal dilatation of the aorta, which was noted to be at the right of and anterior to the pulmonary artery. Both great vessels arose from the right ventricle. Other echocardiographic findings included dilated right atrium, dilated and hypertrophied right ventricle with volume and pressure overload, global left ventricular hypokinesia with mild systolic dysfunction, and moderate to severe aortic regurgitation. The above complex congenital anomalies were confirmed via transesophageal echocardiogram and cardiac magnetic resonance imaging (MRI). Furthermore, pulmonary valve stenosis and aortopulmonary window, that was 3.5 centimeters in length located at the level of the proximal ascending aorta and main pulmonary artery, were seen on the MRI.

Various cardiac imaging modalities aided in cinching the diagnosis for this very rare complex congenital case in an adult reaching the third decade of life. Palliative care was deemed best for this patient due to the severity of her cardiac condition.

Abstract P1445 Figure 1.

Evaluation of the brain functional activities in rats various location-endometriosis pain model

Background

Endometriosis (EM) is a common gynecological disease in women of reproductive age. These patients in approximately 80% suffer the various degree pain. This study will investigate synergistically the mechanism of the higher-position central sensitization and offer a pre-clinical experiment evidence for treatment of various location-EM patients with pain.

Methods

Twenty Sprague-Dawley rats were induced three types EM including abdominal EM (n=5), gastrocnemius EM (n=5) and ovary EM group (n=5) and one sham control group (n=5). All groups were measured the pain sensitization by hotplate test, then scanned by the functional magnetic resonance imaging (fMRI). The resting-state fMRI (rs-fMRI) date was analyzed using regional homogeneity (ReHo) approach to find out the abnormal functional activity brain regions. Nissl staining method observed the state of neurons in aberrant ReHo signal brain regions.

Results

Rats with EM pain sensitization were increased in abdominal EM and gastrocnemius EM than ovary EM group and sham control. The ReHo value is decreased in gastrocnemius EM in right thalamus and left olfactory tubercle compared with other three groups. The number of neurons was decreased; cavitation around nucleus, and pyknotic homogenous nuclei. Nissl bodies were stained deeply, and the shape was irregular in gastrocnemius EM by Nissl staining in right thalamus. In left olfactory tubercle, there was no significant difference in 4 groups.

Conclusions

The thalamus may be the potential key brain region for the central sensitization mechanism of various location-EM pain. The oxidative activation may be weakened in thalamus in gastrocnemius EM group with more severe pain. This finding could lend support for future research on the imageology and pathology of various location-EM pain.

The financial burden of acute odontogenic infections: the South Australian experience

BACKGROUND

Acute odontogenic infections are a common surgical emergency managed by public hospitals in Australia which cause considerable patient morbidity and occasionally, mortality. Despite posing a significant public health burden, Australian data evaluating the cost of the management of these patients are lacking. This study assessed the patient and treatment variables associated with inpatient management of deep odontogenic infections, and their respective financial impact, at a statewide Oral & Maxillofacial service.

METHODS

A retrospective audit was carried out of patients with deep odontogenic infections at our institution, over a 7-year period. The primary outcome was the total cost of admission. Secondary outcomes included treatment received, operating room time, return-to-theatre, length of admission (LOS), and intensive care unit (ICU) use. Cost variables were assessed against the total LOS and ICU use to determine clinical predictors affecting outcome.

RESULTS

Four hundred and sixty two patients met the inclusion criteria. The average cost per patient was $12 228 Australian Dollars. After multivariate analysis, variables most significantly associated with increased cost of care and LOS were high-risk infections with airway compromise, high admission white cell count and age.

CONCLUSION

Hospital-based management of deep-space odontogenic infections engender significant costs compared to early primary care intervention such as a dental extraction ($181/extraction).

4113Glucose lowering drugs or strategies, major adverse cardiovascular events and heart failure outcomes, and association with weight loss - meta-analysis of large cardiovascular outcome trials

Background

Glucose lowering drugs or strategies (GLDS) have varied effects on major adverse cardiovascular events (MACE) and heart failure (HF) in cardiovascular outcomes trials. Mechanisms driving cardiovascular risk reduction remain elusive.

Methods

We searched MEDLINE, PubMed, and meeting abstracts up to 11/21/2018 for large GLDS cardiovascular outcome trials (CVOTs) in patients with or at risk for type 2 diabetes. Primary endpoints of MACE and HF were evaluated with random effects risk ratios (RR) and explored by baseline CVD subgroups and meta-regression by weight change across treatment arms.

Results

In 27 GLDS CVOTs, a total 207,820 patients, median age 63 years, 64% male, 64% CVD and 11% with prior HF were studied over a mean 3.8 years with 20,118 (10%) patients having MACE and 7,212 (4%) a HF event. Compared with standard care, GLDS overall lowered MACE (RR 0.92, P<0.ehz745.01171) but not HF (RR 1.01, P=0.91). Across GLDS, the magnitude and directionality varied modestly for MACE RR (P-int=0.07) but markedly for HF (P-int<0.ehz745.01171). Meta-regression showed a change in HF RR by 6% (95% CI 3%-9%) per 1 kg weight gain/loss between treatment arms (P=0.0006; Figure). In 9 trials of GLDS that achieved marked weight loss (lifestyle, GLP1 agonists, SGLT2 inhibitors), MACE benefit was confined to patients with baseline CVD (RR 0.89 [0.84–0.95] versus without (RR 1.02 [0.91–1.15]; P-int=0.01) with consistent HF effect (RR 0.80 [0.72–0.88] vs RR 0.76 [0.56–1.03]; P-int=0.74).

Heart Failure Risk and Changes in Weight

Conclusion

HF outcomes were improved with GLDS that lower weight. Among diabetes GLDS that lower weight, there was a robust risk reduction in atherothrombotic and heart failure events, with the MACE benefit confined to patients with established CVD.

Acknowledgement/Funding

Heart and Stroke Foundation

5970Morbidity and mortality in patients precluded for transvenous pacemaker implantation: experience with the Micra transcatheter pacemaker

Background

The Micra transcatheter pacemaker has proven to be a safe and effective alternative to transvenous pacemakers (TVPs). However, the safety profile after Micra implantation in patients deemed poor candidates for TVPs is poorly understood.

Purpose

To evaluate the safety and all-cause mortality outcomes in Micra recipients stratified by whether or not they were precluded for therapy with TVP.

Methods

Micra patients from the Micra Transcatheter Pacing (IDE) Study, Continued Access (CA) study, and Post-Approval Registry (PAR) were divided into groups based upon whether or not the implanting physician considered the patient to be precluded from receiving a transvenous pacing system. All-cause mortality was compared between the Micra patient groups and patients receiving a single-chamber transvenous pacing system (SC-TVP) since 2010 from the Medtronic product surveillance registry using univariate and multivariate Cox models.

Results

Among 2,819 patients who underwent a Micra implant attempt, the overall major complication rate through 24 months was 3.5%. In these patients, 548 were deemed precluded from TVP implantation. Prior device infection or bacteremia (38.9%), venous access issues (36.1%) and thrombosis (10.2%) were amongst the most common causes of preclusion for TVP implantation. These patients were younger (71.7 vs. 76.7 years), more frequently on hemodialysis (26.3% vs. 2.5%), and more often had a prior CIED implanted (38.4% vs. 4.4%) than non-precluded patients. Over an average follow-up of 13.5±11.1 months, all-cause mortality was significantly higher in precluded Micra patients compared with SC-TVP patients (HR: 2.16, 95% CI: 1.54–3.2, P<0.001) (Figure 1). However, there was no significant difference in all-cause mortality when comparing non-precluded Micra patients and SC-TVP patients (HR: 1.12, 95% CI: 0.86–1.44, P=0.401). Acute all-cause death (within 1 month) among Micra patients was 2.74% and 1.32% in the precluded and non-precluded TVP groups, respectively. The procedure-related death rate was 0.55% for the TVP precluded group and 0.13% for the not precluded group (P=0.092). The major complication rate through 24-months was similar between the two Micra groups (4.0% vs 3.4%, P=0.630).

All-cause mortality for Micra and SC-TVP

Conclusion

The overall safety profile of Micra remains is in line with previously reported data. All-cause mortality risk (both acute and long term) appears to be higher in patients who were precluded from receiving TVP.

Acknowledgement/Funding

Supported by Medtronic

Pathological findings following risk-reducing salpingo-oophorectomy in BRCA mutation carriers: A systematic review and meta-analysis

OBJECTIVE

To evaluate the benefit of risk-reducing salpingo-oophorectomy (RRSO) by estimating the pathological positive rate of occult lesions, including serous tubal intraepithelial carcinoma (STIC) and occult cancers (OCCs).

METHODS

BRCA1/2 mutation carriers who underwent RRSO in a Chinese study center between 2014 and 2018 were included. A literature review was performed, followed by a meta-analysis of the literature to further validate the findings.

RESULTS

Twenty-four BRCA1/2 mutation carriers who underwent RRSO were identified; one patient (4.2%) had STIC, and one patient (4.2%) had occult fallopian tube cancer complicated by STIC. Thirty-four articles were ultimately included in the meta-analysis. Of the reported cases of OCC, 61.3% occurred in the fallopian tubes and 32.3% in the ovaries, and 81.5% were in the early stages. The estimated rate of overall pathological positive events was 5%. The estimated rates of overall STIC events and OCC were 1% and 3%, respectively. The rates of STIC and OCC were 1% and 3%, respectively, for BRCA1 mutation carriers and 1% and 1%, respectively, for BRCA2 mutation carriers. No significant difference was observed between the results of a routine examination of pathological sections and those of the Sectioning and Extensively Examining the Fimbriae (SEE-FIM) protocol.

CONCLUSIONS

This study is the first report of RRSO results in China. In this systematic review, the positive rates of STIC or OCC after RRSO were no more than 3%, which are 200-fold higher than the risk of the general population. The use of a strict SEE-FIM protocol would likely increase positive results.

Efficacy of different surgical approaches in the clinical and survival outcomes of patients with early-stage cervical cancer: protocol of a phase III multicentre randomised controlled trial in China

INTRODUCTION

In the last three decades, minimally invasive surgery (MIS) for radical hysterectomy (RH) has become a popular treatment option for early-stage cervical cancer. However, a recently published randomised controlled trial (LACC trial) and an epidemiological study in the USA revealed strong evidence against the survival advantage of MIS for RH. However, the influencing factors of research centres and the learning curves of surgeons in these studies lacked sufficient evaluation. The efficacy of different surgical approaches for early-stage cervical cancer in the clinical and survival outcomes remains to be validated.

METHODS AND ANALYSIS

Patients diagnosed with FIGO (2009) stage IA1 (with lymphovascular space invasion), IA2 or IB1 cervical cancer with histological subtype of squamous cell carcinoma, adenocarcinoma or adenosquamous carcinoma will be recruited in this multicentre randomised controlled study. Patients will be randomly assigned to undergo MIS (robot-assisted or laparoscopic RH) or abdominal RH. Within 2 years, 1448 patients in 28 centres in China will be recruited to meet the criteria of a non-inferiority threshold of HR of 1.6 with bilateral nominal α <0.05 and power of 0.8. All surgeries will be performed by the indicated experienced surgeons. At least 100 RH cases in the individual past one decade of practice will be analysed as proof of learning curves. The primary objective of this study is 5-year disease-free survival. The secondary objectives include the overall survival rate, progression-free survival rate, disease-free survival rate, cost-effectiveness and quality of life.

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board of Peking Union Medical College Hospital and is filed on record by all other centres. Written informed consent will be obtained from all eligible participants before enrolment. The results will be disseminated through community events, academic conferences, student theses and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03739944.

Ultrastructure of duck Tembusu virus observed by electron microscopy with negative staining

Duck Tembusu virus (DTMUV) is a newly emerging enveloped flavivirus. This study shows the ultrastructure of DTMUV using viral purification, negative staining and electron microscopy. Electron microscopic examinations revealed mature DTMUV particles with 50 to 75 nm in diameter and typical enveloped flavivirus structure that consists of the internal nucleocapsid, an inner layer of lipid bilayer and an external layer of E glycoprotein ectodomain. Particles appear to be mostly spherical. In particular, RNA core is deep colored and dense, both capsid and lipid bilayer are clearly visible, the capsid forms regular hexagon, and E glycoprotein ectodomain forms a fringe instead of visible spikes. Thus, this report about the clear ultrastructure of the DTMUV particles will be the major driving forces behind structural biology of DTMUV.

[Impact of hypoxia-reoxygenation environment on autophagy level of osteoblasts]

Objective: To investigate the impact of hypoxia-reoxygenation environment on the level of autophagy in osteoblasts. Methods: Osteoblasts were purified from the skulls of newborn SD rats within 24-48 hours by tissue block adherence culture and differential centrifugation. The osteoblasts were identified by alizarin red staining and alkaline phosphatase staining. The third generation osteoblasts were cultured in normal state and randomly divided into four groups: group A was cultured under normal condition for 36 hours; group B was cultured under normal condition for 18 hours, then under hypoxia for 18 hours; group C was cultured under hypoxia for 36 hours; group D was cultured under hypoxia for 18 hours, and then under normal condition for 18 hours. The ability to form calcium nodules of osteoblasts in the four groups was observed after culture. The proliferation activity of osteoblasts was detected by CCK-8 assay. The expressions of autophagy specified gene Beclin 1, microtubule-associated protein light chain 3(LC3) and collagen Ⅰ(COL-Ⅰ), bone morphogenetic protein 2 (BMP-2) genes were detected by real time polymerase chain reaction (RT-PCR), and the protein expressions of Beclin 1, LC3-Ⅰ,LC3-Ⅱ and P62 were detected by immunoblotting. Results: Alizarin red staining showed that osteoblasts in group A had the strongest calcification ability, and calcification ability of osteoblasts in group B,C and D lowered gradually, and it was lowest in group D. The proliferative activity under the CCK-8 detection in group A, B, C and D was 98%±8%, 90%±8%,82%±9%,76%±8%, respectively (F=35.764, P=0.000). The mRNA expression of Beclin 1, LC3-Ⅱthe 4 groups increased gradurally (group D> group C> group B> group A)(F=38.327, 16.583, both P<0.05); and the mRNA expression of COL-Ⅰ, BMP-2 decreased gradually in the 4 groups (group A> group B> group C> group D) (F=20.387, 12.426, both P<0.05). The protein expression of Beclin 1,LC3-Ⅱ/LC3-Ⅰ increased gradually in the groups (group D>group C>group B>group A) (F=26.843, 28.576, bothP<0.05), and the expression of P62 protein decreased gradually (F=18.946, P=0.011). Conclusions: Hypoxia-reoxygenation environment can reduce the proliferation activity of osteoblasts and up-regulate the expression of autophagy-related genes in osteoblasts. Anoxic reoxygenation environment promotes the increasing of autophagy levels in osteoblasts.

Abstract OT2-10-01: Treatment burden and capacity to manage care among patients with breast cancer

Patients with breast cancer spend significant time1, effort, and financial resources2 to combat the disease for years after their diagnosis. The large volume of healthcare tasks can cause patients to become overburdened, leading to reduced adherence with care plans and worse outcomes3. On the other hand, certain patient characteristics such as physical resilience, financial well-being, and supportive family environments increase patients' capacity to manage care4. Assessing treatment burden and capacity when prescribing care has been applied to populations such as diabetes patients5. We are investigating this paradigm in treatment of patients with breast cancer. The goal of this preliminary study is to identify significant factors that contribute to treatment burden, capacity to manage care, and outcomes of overburden for patients with breast cancer.

Examples of treatment burden, capacity to manage care, and outcomes of overburden in patients with breast cancerTreatment burdenCapacity to manage careOutcomes of overburdenTraveling long distances for careAccess to reliable transportationReduced spending on food, utilities, or other necessitiesPaying for child care during chemotherapyFlexibility in informal caregivers' schedulesMissed appointment with medical oncologistRemembering to take medications with mealsMedical understanding or knowledgeWorse than expected side effectsReporting adverse eventsProficiency with mobile deviceTrip to emergency room

Through literature review, interviews with survivors, and expert panels of navigators and providers, we will develop a survey instrument given to patients at the time of diagnosis. The survey will assess patient capacity and help providers give treatment options based on attributes of the patient. Additionally, we will attempt to correlate survey results with treatment burden measures derived from electronic health record data at a population level1. With treatment personalized for patient capacity, patients should be better able to adhere to care plans leading to improved quality of life during treatment and beyond.

Acknowledgements: The authors would like to thank Cheryl Jernigan, our patient advocate mentor, for her guidance in this project. We would also like to thank the Susan G. Komen Foundation for their support of this research.

References:

1. Cheng, A. C. & Levy, M. A. Data Driven Approach to Burden of Treatment Measurement: A Study of Patients with Breast Cancer. AMIA Annu. Symp. proceedings. AMIA Symp. 2016, 1756–1763 (2016).

2. Zafar, S. Y. et al. The financial toxicity of cancer treatment: a pilot study assessing out-of-pocket expenses and the insured cancer patient's experience. Oncologist. 18, 381–90 (2013).

3. Mair, F. S. & May, C. R. Thinking about the burden of treatment. BMJ. 349, g6680–g6680 (2014).

4. Boehmer, K. R., Shippee, N. D., Beebe, T. J. & Montori, V. M. Pursuing Minimally Disruptive Medicine: Correlation of patient capacity with disruption from illness and healthcare-related demands. J. Clin. Epidemiol. (2016).

5. Ishii, H. et al. Reproducibility and Validity of a Questionnaire Measuring Treatment Burden on Patients with Type 2 Diabetes: Diabetic Treatment Burden Questionnaire (DTBQ). Diabetes Ther. 9, 1001–1019 (2018).

Citation Format: Cheng A, Levy M. Treatment burden and capacity to manage care among patients with breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-10-01.

Steroid-Refractory Autoimmune Myocarditis after Pembrolizumab Therapy: Failure of Equine Anti-Thymocyte Globulin to Prevent Heart Failure

While immune checkpoint inhibitors (ICIs) are improving outcomes for many cancers, they can have severe adverse effects. Though cardiac immune-related adverse effects (irAEs) are rare, they have considerable morbidity and mortality. Prior case studies have demonstrated successful treatment of ICI induced autoimmune myocarditis with a variety of immunosuppressive regimens. This case describes steroid-refractory autoimmune myocarditis after treatment with pembrolizumab. Treatment with equine anti-thymocyte globulin, a regimen previously documented to reverse ICI induced autoimmune myocarditis, temporarily improved clinical status and cardiac biomarkers, however eventually failed to prevent progression to heart failure and cardiovascular death. This case highlights the importance of early stress-dose steroids, identifies troponin as a potential marker of treatment response, and underscores the value of collaboration between oncology and cardiology for optimal management.

Construction of expression vectors of capsid proteins from goose parvovirus and investigation of the immunogenicity

Goose parvovirus (GPV) is a highly contagious and lethal disease in goslings and Muscovy ducklings, and is of concern to the waterfowl industry. With the aim of comparing the cellular immunogenicity of three capsid proteins of GPV, plasmids of pcDNA3.1(+)-VP1, pcDNA3.1(+)-VP2, and pcDNA3.1(+)-VP3 were constructed, and the recombinant protein VPs were expressed using an eukaryotic expression system. We detected the levels of immune-related genes (CD4, CD8α, IL-1β, IL-6, IFNα, IFNγ, and IFNλ) in both goose embryo fibroblasts (GEF) and goose peripheral blood mononuclear cells (PBMCs) cellular models. The immune response conferred by a VP2 DNA vaccine in vivo was observed in a time course. Our data suggested that the cellular immune response to VP2 and VP3 was stronger than that to VP1, while VP2 and VP3 shared similar cellular immune reactivity. In addition, vaccination with VP2 plasmid can induce high level of IgY antibody that continued to increase through 28 days post vaccination. Therefore, our findings shed light on the host cellular immune response against GPV capsid proteins. Keywords: GPV; capsid proteins; cellular immune response; humoral immunity.