Bereavement, Memorial Attendance, and Mental Health During the COVID-19 Pandemic: Longitudinal Results from the Nurses' Health Study

BACKGROUND

Mortality increased during the COVID-19 pandemic. Many bereaved individuals were not able to gather to memorialize their loved ones, yet it is unknown if this contributed to worsening mental health.

OBJECTIVE

Examine the association of bereavement in the early part of the COVID-19 pandemic with subsequent psychological distress and the role of memorial attendance in reducing psychological distress among the bereaved.

DESIGN, SETTINGS, SUBJECTS

In May 2020, 39,564 older females from the Nurses' Health Study II enrolled in a longitudinal COVID-19 substudy (meanage = 65.2 years, SD = 4.5).

METHODS

Linear regression analyses estimated associations of bereavement reported between March and October, 2020 with subsequent psychological distress between January and October 2021, adjusting for sociodemographic and prepandemic depression symptoms. Secondary models examined associations between memorial attendance and psychological distress.

RESULTS

Bereavement during the early part of the COVID-19 pandemic was associated with higher psychological distress (adjusted β = 0.21, 95% CI: 0.15, 0.26) assessed over the next year. Among the bereaved, memorial attendance was associated with lower psychological distress (in-person: adjusted β = -0.41, 95% CI: -0.53, -0.29; online: adjusted β = -0.24, 95% CI: -0.46, --0.02).

CONCLUSION

Attending memorials was associated with lower subsequent psychological distress among bereaved older females.

Suffering, psychological distress, and well-being in Indonesia: A prospective cohort study

Research on the subjective experience of suffering has typically focussed on older clinical samples living in Western, educated, industrialised, rich, and democratic (WEIRD) countries. To further extend the existing body of empirical research on suffering to less WEIRD contexts, we use three waves of data (Wave 1: December 2020; Wave 2: January 2021; Wave 3: February 2021) from a sample of nonclinical Indonesian adults (n = 594) to examine associations between suffering, two indices of psychological distress, and 10 facets of well-being. In our primary analysis, we estimated a series of multiple regression models that adjusted for a range of sociodemographic characteristics, financial and material stability, religious/spiritual factors, prior values of overall suffering, and prior values of each outcome assessed in Wave 1. Results indicated that overall suffering assessed in Wave 2 was associated with an increase in both indices of psychological distress and a decrease in eight facets of well-being assessed in Wave 3. Using a similar analytic approach, results from a secondary analysis indicated that higher scores on both indices of psychological distress and lower scores on seven of the well-being facets assessed in Wave 2 were associated with worse subsequent overall suffering assessed in Wave 3. These findings contribute to empirical literature on the implications of suffering for well-being.

Paradoxical Increase of Permeability and Lipophilicity with the Increasing Topological Polar Surface Area within a Series of PRMT5 Inhibitors

An imidazolone → triazolone replacement addressed the limited passive permeability of a series of protein arginine methyl transferase 5 (PRMT5) inhibitors. This increase in passive permeability was unexpected given the increase in the hydrogen bond acceptor (HBA) count and topological polar surface area (TPSA), two descriptors that are typically inversely correlated with permeability. Quantum mechanics (QM) calculations revealed that this unusual effect was due to an electronically driven disconnect between TPSA and 3D-PSA, which manifests in a reduction in overall HBA strength as indicated by the HBA moment descriptor from COSMO-RS (conductor-like screening model for real solvation). HBA moment was subsequently deployed as a design parameter leading to the discovery of inhibitors with not only improved passive permeability but also reduced P-glycoprotein (P-gp) transport. Our case study suggests that hidden polarity as quantified by TPSA-3DPSA can be rationally designed through QM calculations.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Identification of potential antiviral compounds against SARS-CoV-2 structural and non structural protein targets: A pharmacoinformatics study of the CAS COVID-19 dataset

SARS-CoV-2 is a newly discovered virus which causes COVID-19 (coronavirus disease of 2019), initially documented as a human pathogen in 2019 in the city of Wuhan China, has now quickly spread across the globe with an urgency to develop effective treatments for the virus and emerging variants. Therefore, to identify potential therapeutics, an antiviral catalogue of compounds from the CAS registry, a division of the American Chemical Society was evaluated using a pharmacoinformatics approach. A total of 49,431 compounds were initially recovered. After a biological and chemical curation, only 23,575 remained. A machine learning approach was then used to identify potential compounds as inhibitors of SARS-CoV-2 based on a training dataset of molecular descriptors and fingerprints of known reported compounds to have favorable interactions with SARS-CoV-2. This approach identified 178 compounds, however, a molecular docking analysis revealed only 39 compounds with strong binding to active sites. Downstream molecular analysis of four of these compounds revealed various non-covalent interactions along with simultaneous modulation between ligand and protein active site pockets. The pharmacological profiles of these compounds showed potential drug-likeness properties. Our work provides a list of candidate anti-viral compounds that may be used as a guide for further investigation and therapeutic development against SARS-CoV-2.

The nature effect in motion: visual exposure to environmental scenes impacts cognitive load and human gait kinematics

Prolonged exposure to urban environments requires higher cognitive processing resources than exposure to nature environments, even if only visual cues are available. Here, we explored the moment-to-moment impact of environment type on visual cognitive processing load, measuring gait kinematics and reaction times. In Experiment 1, participants (n = 20) walked toward nature and urban images projected in front of them, one image per walk, and rated each image for visual discomfort. Gait speed and step length decreased for exposure to urban as compared with nature scenes in line with gait changes observed during verbal cognitive load tasks. We teased apart factors that might contribute to cognitive load: image statistics and visual discomfort. Gait changes correlated with subjective ratings of visual discomfort and their interaction with the environment but not with low-level image statistics. In Experiment 2, participants (n = 45) performed a classic shape discrimination task with the same environmental scenes serving as task-irrelevant distractors. Shape discrimination was slower when urban scenes were presented, suggesting that it is harder to disengage attention from urban than from nature scenes. This provides converging evidence that increased cognitive demands posed by exposure to urban scenes can be measured with gait kinematics and reaction times even for short exposure times.

Identification of TNO155, an Allosteric SHP2 Inhibitor for the Treatment of Cancer

SHP2 is a nonreceptor protein tyrosine phosphatase encoded by the PTPN11 gene and is involved in cell growth and differentiation via the MAPK signaling pathway. SHP2 also plays an important role in the programed cell death pathway (PD-1/PD-L1). As an oncoprotein as well as a potential immunomodulator, controlling SHP2 activity is of high therapeutic interest. As part of our comprehensive program targeting SHP2, we identified multiple allosteric binding modes of inhibition and optimized numerous chemical scaffolds in parallel. In this drug annotation report, we detail the identification and optimization of the pyrazine class of allosteric SHP2 inhibitors. Structure and property based drug design enabled the identification of protein-ligand interactions, potent cellular inhibition, control of physicochemical, pharmaceutical and selectivity properties, and potent in vivo antitumor activity. These studies culminated in the discovery of TNO155, (3S,4S)-8-(6-amino-5-((2-amino-3-chloropyridin-4-yl)thio)pyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-amine (1), a highly potent, selective, orally efficacious, and first-in-class SHP2 inhibitor currently in clinical trials for cancer.

SAT0445 TRABECULAR BONE SCORE IMPROVES FRACTURE RISK STRATIFICATION IN PATIENTS WITH REDUCED BONE MINERAL DENSITY

Background:

Trabecular bone score (TBS) is a textural index of bone microarchitecture and has been found to be related to 3D bone structure. A number of cohort studies have demonstrated the value of TBS as an independent fracture risk in clinical trials. Yet, very little is known about the performance and clinical value of TBS in real life practice.

Objectives:

To investigate the sensitivity and specificity of TBS in identifying prevalent fractures when compared with bone mineral density (BMD) measured by DXA. To evaluate the added value of TBS in fracture risk prediction above that obtained from DXA.

Methods:

Consecutive patients aged ≥ 18 with BMI 15-37 attnding a DXA plus TBS assessment were considered eligible. Sensitivity, specificity, and area under the curve (AUC) for prevalent major osteoporotic fracture (MOF) and clinical vertebral fractures (VF) were assessed for the following parameters: BMD lowest T-score ≤-2.5 (neck of femur, total hip, or spine), TBS T-score ≤-2.5, and either TBS or BMD T-score ≤-2.5. BMD categories (normal, osteopenia, and osteoporosis) were stratified by TBS T-score: normal (T-score ≥-1), moderate (-1≥T-score≥-2.5), and degraded TBS (T-score ≤-2.5) resulting in 9 risk groups. Odds ratios were calculated for all risk categories and fracture prevalence was compared between the best and worst TBS strata at each BMD level using chi-square test.

Results:

540 patients (87% females, 68.1 ± 11.6 years) were included. 238 (44%) had MOF including 81 (15%) clinical VF. For MOF, BMD had higher sensitivity (49.6% vs 30.7%), lower specificity (68.2% vs 82.1%), and similar AUC (0.59 vs 0.56) versus TBS. For VF, the sensitivity, specificity and AUC for BMD were 60%, 64%, and 0.62 respectively versus 42%, 79.7%, and 0.61 for TBS. Combining TBS and BMD (either T-score ≤ -2.5) increased the sensitivity to 63% for MOF and 75.3% for VF without affecting AUC (0.6 and 0.64 respectively). Patients with osteoporosis and degraded TBS had the highest OR of 2.65 for MOF and 3.8 for VF. The fracture risk increased at the same level of BMD when TBS was degraded. Numerically, the risk of MOF increased steadily from strata 1 to 9 and was statistically significant for osteoporosis with degraded TBS and osteoporosis with moderate TBS. When both TBS and BMD were normal, the risk of fracture was significantly reduced. In the osteopenia and osteoporosis BMD categories, patients with degraded TBS had significantly higher prevalence of fracture compared to those with normal TBS in the same BMD category.

Conclusion:

Fracture risk stratification can be improved when TBS is added to BMD. The sensitivity of predicting fracture may also improve when TBS and BMD are combined. Patients with both normal TBS and BMD have the lowest fracture risk, whereas those with degraded TBS and osteoporosis have the highest risk of fracture and should be targeted for early or more aggressive treatment.

References:

[1]Hans D et al. J Bone Miner Res. 2011;26(11).

[2]McCloskey EV et al. Calcif Tissue Int. 2015;96(6).

Table 1.

Prevalence and risk of MOF and VF according to BMD stratified by TBS T-score

Patients within categoryNumber of MOFOR for MOFNumber of VFOR for VFNormal BMD & TBS497 (14.3%)0.19(0.08-0.43)*00.83(0.80-.87)*Normal BMD moderate TBS195 (26.3%)0.44(0.16-1.24)2 (10.5%)0.66(0.15-2.9)Normal BMD degraded TBS72 (28.6%)0.50(0.1-2.6)1 (14.3%)0.94(0.11-7.9)Osteopenia normal TBS9633 (34.4%)0.61(0.39-0.97)7 (7.3%)0.39(0.18-0.88)*Osteopenia moderate TBS9843 (43.9%)0.99(0.64-1.54)11 (11.2%)0.67(0.34-1.32)Osteopenia degraded TBS5730 (52.6%)1.47(.085-2.55)11 (19.3%)1.41(0.7-2.86)Osteoporosis normal TBS3918 (46.2%)1.1(0.57-2.1)6 (15.4%)1(0.42-2.6)Osteoporosis moderate TBS11259 (52.7%)1.55(1.02-2.35)*21 (18.8%)1.42(0.82-2.45)Osteoporosis degraded TBS6341 (65.1%)2.65(1.53-4.59)*22 (34.9%)3.8(2.12-6.83)*Total54023881

Acknowledgments:

Bone density team, Robert Jones and Agnes Hunt Orthopaedic Hospital

Disclosure of Interests:

None declared

SAT0479 IMPACT OF TRABECULAR BONE SCORE ON INTERVENTION THRESHOLD FOR BONE SPARING THERAPY IN PATIENTS REFERRED FOR BONE MINERAL DENSITY

Background:

Trabecular bone score (TBS) is an index of skeletal quality that has been validated as an independent risk factor for fracture and incorporated into fracture risk assessment (FRAX). TBS provides information on bone microarchitecture not captured from standard bone mineral density (BMD) measured by dual energy X-ray absorptiometry (DXA). Nonetheless, the clinical implications of using TBS in routine practice are not yet fully understood and warrant further evaluation.

Objectives:

To determine whether lumbar TBS can have an impact on clinician’s treatment threshold derived from DXA and clinical risk factors: does the addition of TBS to DXA measurements make the clinician more or less likely to recommend bone sparing therapy?

Methods:

A cross-sectional study at a tertiary metabolic bone centre in the West Midlands region of England. Three expert metabolic bone physicians, two rheumatologists and one elderly care, assessed consecutive patients referred for a DXA scan ± clinic review and provided treatment recommendations with and without TBS. Patients ≥ 18 years old with BMI of 15-37 who were not on bone sparing therapy were considered eligible. TBS was defined according to T-score as normal (T-score ≥ -1), moderate (-1 > T-score ≥ -2.5) or degraded (T-score ≤ -2.5). TBS groups were stratified by BMD T-scores (normal, osteopenia, or osteoporosis) using minimum T-score of total hip, femoral neck, and spine to identify categories in which TBS may be of more clinical use. The main outcome measure was the proportion of change in clinician’s treatment threshold between BMD alone and BMD plus TBS. The difference was assessed for significance using Chi-square test. Additionally, the change in UK National Osteoporosis Guideline Group (NOGG) threshold was also assessed using TBS-adjusted FRAX scores. Correlations between BMD-TBS strata and the change in intervention threshold (yes/no) were carried out using Spearman test.

Results:

540 patients were analysed. The inclusion of TBS resulted in 8.2% change in clinician’s treatment threshold (p <0.001) shifting the outcome 6.5 % for and 1.7 % against treatment. More than half of the cases in which the clinical decision was changed were for patients with osteopenia and degraded TBS (significant correlation; P <0.001). NOGG intervention threshold was changed in 7.4% of the cases (P<0.001); 6.1% for and 1.3% against treatment. 37.5% of NOGG changed outcome was related to osteopenia with degraded TBS (p<0.001). Kappa agreement between the clinician and NOGG was fair at 0.42 (p<0.001).

Conclusion:

These results demonstrate that using TBS in routine clinical practice is most likely to impact treatment decision in patients with osteopenia who have compromised bone microarchitecture. Incorporating TBS in routine DXA scans may lead to a net increase in bone protective therapy of approximately 5%. It is unknown whether adopting such an approach universally can reduce future fracture risk, and prospective studies are needed to address this question.

References:

[1]Hans D et al. J Bone Miner Res. 2011;26(11):2762-9.

[2]McCloskey EV et al. Calcif Tissue Int. 2015;96(6):500-9.

Table 1.

Demographic and baseline characteristics (n = 540)

Female470 (87%)Age (years)68.1 ± 11.6Body mass index (BMI)26.2 ± 4.6Femoral neck T-score-1.80 ± 1.04Total hip T-score-1.32 ± 1.07Lumbar spine T-score-1.37 ± 1.42Lumbar spine TBS1.32 ± 0.13Major osteoporotic fractures238 (44%)Spinal fractures81 (15%)FRAX major osteoporotic fracture14.43 ± 9.03FRAX hip fracture4.60 ± 6.20TBS-adjusted FRAX major osteoporotic fracture13.82 ± 8.80TBS-adjusted FRAX hip fracture4.45 ± 5.73Figure 1.

Distribution of changed clinical treatment threshold in normal, moderate, and degraded TBS according to BMD T-score

Acknowledgments:

Bone density unit &Rheumatology team, Robert Jones and Agnes Hunt Orthopaedic Hospital

Disclosure of Interests:

None declared

Development of a national Department of Veterans Affairs mortality risk prediction model among patients with cirrhosis

Objective

Cirrhotic patients are at high hospitalisation risk with subsequent high mortality. Current risk prediction models have varied performances with methodological room for improvement. We used current analytical techniques using automatically extractable variables from the electronic health record (EHR) to develop and validate a posthospitalisation mortality risk score for cirrhotic patients and compared performance with the model for end-stage liver disease (MELD), model for end-stage liver disease with sodium (MELD-Na), and the CLIF Consortium Acute Decompensation (CLIF-C AD) models.

Design

We analysed a retrospective cohort of 73 976 patients comprising 247 650 hospitalisations between 2006 and 2013 at any of 123 Department of Veterans Affairs hospitals. Using 45 predictor variables, we built a time-dependent Cox proportional hazards model with all-cause mortality as the outcome. We compared performance to the three extant models and reported discrimination and calibration using bootstrapping. Furthermore, we analysed differential utility using the net reclassification index (NRI).

Results

The C-statistic for the final model was 0.863, representing a significant improvement over the MELD, MELD-Na, and the CLIF-C AD, which had C-statistics of 0.655, 0.675, and 0.679, respectively. Multiple risk factors were significant in our model, including variables reflecting disease severity and haemodynamic compromise. The NRI showed a 24% improvement in predicting survival of low-risk patients and a 30% improvement in predicting death of high-risk patients.

Conclusion

We developed a more accurate mortality risk prediction score using variables automatically extractable from an EHR that may be used to risk stratify patients with cirrhosis for targeted postdischarge management.

Opioid Use is Associated with Higher Severity-Adjusted Episode Costs in Patients with Conservatively Managed Degenerative Joint Disease of the Back and Neck

BACKGROUND

Opioid use and misuse are urgent health issues. Previous studies suggest that opioid use increases healthcare resource use but severity adjustment is lacking.

OBJECTIVE

The objective of this study was to evaluate the severity-adjusted cost difference between opioid users and non-users among patients with conservatively managed degenerative joint disease of the spine within a large commercial health plan population in the United States.

METHODS

A retrospective observational study was performed using a national commercial database covering 531,819 patients aged 18-64 years with non-surgically managed cervical or lumbar degenerative spine disease during 2015-6. Patients were grouped based on whether there was evidence for an opioid prescription. Costs for the opioids themselves were excluded. Severity adjustment, on an ascending integer scale from 1 to 4, was performed based on member demographics, clinical comorbidities, disease progression indicators, and complications.

RESULTS

Median episode costs for patients given opioids were approximately twice that for patients not given opioids after severity adjustment. For patients with episodes in both years and stable severity, patients with new prescriptions for opioids in 2016 doubled their median 2015 costs, and patients who had opioids discontinued in 2016 had a 60% cost reduction. Episode costs showed a nearly linear increase based on the length of time taking opioids, as well as with a higher average daily dose. Cost increases with opioids were broad across service categories even when comparing within the same severity-adjusted episodes of care.

CONCLUSIONS

The data suggest a clinically and statistically significant increase in episode costs associated with opioid use for degenerative joint disease of the spine, both within and between patients, and higher costs with a longer duration of opioid use as well as with higher daily dosages. Given the health consequences surrounding the overuse of opioids, concerted efforts to move towards a non-opioid pain control strategy are needed.

Abstract P1-12-07: Prospective 36-month follow-up to determine changes in body mass index and weight among Chinese breast cancer survivors

Background:Anticancer treatment for breast cancer has been associated with weight gain but such observation has mainly been reported in western patients. More recent data in Asian patients have inconsistent findings. Factors including socio-demographic, clinical and lifestyle may be associated with post-diagnosis weight gain. In this prospective cohort study of women with breast cancer, the objectives were to determine the body mass index (BMI) and weight changes over 36 months after initial diagnosis and the factors associated with such changes.

Methods: Chinese women with newly diagnosed early-stage breast cancer were recruited. Individual woman had her weight measured at breast cancer diagnosis (W0), at study entry (W1) and at 36-month follow-up (W2). Body height was measured at W0. We evaluated change in weight and body mass index (BMI) before and after breast cancer diagnosis.Socio-demographic, clinical and lifestyle factors were assessed to identify potential associated factors with weight changes.

Results: A total of 1133 women with breast cancer had detailed weight measurements at the 3 time-points of assessment. The mean age at diagnosis was 52 years. Fifty-four percent were premenopausal at W1. The proportion of patients with stage 0-I, II and III diseases were 35%, 46% and 19%, respectively.

The proportions of patients who were overweight and obese at the three assessment time-points were 21.2% and 28.5% at W0, 19.7% and 26.6% at W1, and 21.7% and 30.9% at W2 assessment, respectively. When compared to W0, the proportions of women who gained weight within 2-5kg at W1 and W2 were 2.4% and 20.6% respectively, that with weight gain of &gt;5kg at W1 and W2 were 0.5% and 10.0% respectively; 6.1% and 19.6% of women had weight loss &gt;2kg at W1 and W2 respectively.

Compared to W0, the median value of weight change was -0.5 kg (range: -11.4, 18.3) at W1 and 0.6 kg (range: -19.6, 20.5) at W2. On multivariate analysis, only BMI at diagnosis were significantly associated with weight change betweenassessments at diagnosis and W2; the median (range) for weight changes for women who were underweight, normal, overweight and obese were respectively 0.9 (-4.8, 7.6), 0.6 (-13.2, 20.5), 0.5 (-11.5, 13.0) and 0.5 (-19.6, 12.6) kg, p &lt;0.001.

Conclusions: In this prospective study of Chinese women with a history of breast cancer who were followed-up over a 36-months' period, the proportions of women with overweight and obese statuses were relatively stable; weight gain was uncommon among Hong Kong women with breast cancer during the same period. These findings are in contrast with studies conducted in the West, where weight gains were more commonly reported.

Funding: World Cancer Research Fund International (Grant Number WCRF 2010/249 and WCRF 2014/1197)

Citation Format: Yeo W, Lei YY, Cheng AC, Kwok CC, Cheung KL, Lee R, Lee IC, He YQ, Ho S. Prospective 36-month follow-up to determine changes in body mass index and weight among Chinese breast cancer survivors [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 P1-12-07.

Discovery of a ZIP7 inhibitor from a Notch pathway screen

The identification of activating mutations in NOTCH1 in 50% of T cell acute lymphoblastic leukemia has generated interest in elucidating how these mutations contribute to oncogenic transformation and in targeting the pathway. A phenotypic screen identified compounds that interfere with trafficking of Notch and induce apoptosis via an endoplasmic reticulum (ER) stress mechanism. Target identification approaches revealed a role for SLC39A7 (ZIP7), a zinc transport family member, in governing Notch trafficking and signaling. Generation and sequencing of a compound-resistant cell line identified a V430E mutation in ZIP7 that confers transferable resistance to the compound NVS-ZP7-4. NVS-ZP7-4 altered zinc in the ER, and an analog of the compound photoaffinity labeled ZIP7 in cells, suggesting a direct interaction between the compound and ZIP7. NVS-ZP7-4 is the first reported chemical tool to probe the impact of modulating ER zinc levels and investigate ZIP7 as a novel druggable node in the Notch pathway.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Abstract 2084: Conformational activation and allosteric inhibition of SHP2 in RTK-driven cancers

The non-receptor protein tyrosine phosphatase (PTP) SHP2 is an important component of RTK signaling in response to growth factor stimulus and sits just upstream of the RAS-MAPK signaling cascade. The first oncogenic phosphatase to be identified, SHP2 is dysregulated in multiple human diseases including the developmental disorders Noonan and Leopard syndromes, as well as leukemia, lung cancer and neuroblastoma where aberrant activity of SHP2 leads to uncontrolled MAPK signaling. Cancer-associated activating mutations in SHP2 impart an “auto-on” state of the enzyme, boosting basal activity by shifting the equilibrium away from the auto-inhibited state. Reduction of SHP2 activity through genetic knockdown suppresses tumor growth, validating SHP2 as a target for cancer therapy. SHP099, a recently reported potent and selective allosteric inhibitor of SHP2, stabilizes the auto-inhibited form of SHP2 through interactions with the N-terminal SH2 and C-terminal PTP domains of the protein. SHP099 suppresses MAPK signaling in RTK amplified cancers resulting in suppressed proliferation in vitro and inhibition of tumor growth in mouse tumor xenograft models. Together, these data demonstrate the therapeutic potential of SHP2 inhibition in the treatment of cancer and other RAS/MAPK-linked diseases.

Citation Format: Michael G. Acker, Ying-Nan P. Chen, Matthew J. LaMarche, Ho Man Chan, Peter Fekkes, Jorge Garcia-Fortanet, Jonathan R. LaRochelle, Brandon Antonakos, Christine Hiu-Tung Chen, Zhuoliang Chen, Vesselina G. Cooke, Jason R. Dobson, Zhan Deng, Fei Feng, Brant Firestone, Michelle Fodor, Cary Fridrich, Hui Gao, Huai-Xiang Hao, Jaison Jacob, Samuel Ho, Kathy Hsiao, Zhao B. Kang, Rajesh Karki, Mitsunori Kato, Jay Larrow, Laura R. La Bonte, Gang Liu, Shumei Liu, Dyuti Majumdar, Matthew J. Meyer, Mark Palermo, Minying Pu, Edmund Price, Subarna Shakya, Michael D. Shultz, Kavitha Venkatesan, Ping Wang, Markus Warmuth, Sarah Williams, Guizhi Yang, Jing Yuan, Ji-Hu Zhang, Ping Zhu, Stephen C. Blacklow, Timothy Ramsey, Nicholas J. Keen, William R. Sellers, Travis Stams, Pascal D. Fortin. Conformational activation and allosteric inhibition of SHP2 in RTK-driven cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2084. doi:10.1158/1538-7445.AM2017-2084

Abstract LB-017: Disordered methionine metabolism in MTAP/CDKN2A-deleted cancers leads to marked dependence on PRMT5

Metabolic genes are increasingly recognized as targets of somatic genetic alteration in human cancer often leading to profound changes in intracellular metabolite concentrations. 5-Methylthioadenosine Phosphorylase (MTAP) is a key enzyme in the methionine salvage pathway that metabolizes methylthioadenosine (MTA) to adenine and methionine. Its chromosomal position proximal to CDKN2A results in frequent collateral homozygous deletion in a wide range of human cancers. By interrogating data from a large scale deep-coverage pooled shRNA screen across 390 cancer cell line models we found that the viability of MTAP null cancer cells is strongly impaired upon shRNA-mediated depletion of the protein arginine methyltransferase PRMT5. In MTAP deleted cells there is marked accumulation of the substrate MTA and surprisingly, we find that MTA is a specific inhibitor of the catalytic activity of PRMT5. In keeping with these data, knockout of MTAP in an MTAP-proficient cell line led to increased MTA levels and rendered them sensitive to PRMT5 depletion. Moreover, reconstitution of MTAP in an MTAP-deficient cell line fully rescued PRMT5 dependence. Collectively, these findings indicate that the collateral loss of MTAP in CDNK2A deleted cancers leads to accumulation of MTA that thereby creates a hypomorphic PRMT5 state that is selectively sensitized towards further PRMT5 inhibition.

Citation Format: Konstantinos Mavrakis, E Robert McDonald III, Michael R. Schlabach, Eric Billy, Gregory R. Hoffman, Antoine deWeck, David A. Ruddy, Kavitha Venkatesan, Greg McAllister, Rosalie deBeaumont, Samuel Ho, Yue Liu, Yan Yan-Neale, Guizhi Yang, Fallon Lin, Hong Yin, Hui Gao, David Randal Kipp, Songping Zhao, Joshua T. McNamara, Elizabeth R. Sprague, Young Shin Cho, Justin Gu, Ken Crawford, Vladimir Capka, Kristen Hurov, Jeffrey A. Porter, John Tallarico, Craig Mickanin, Emma Lees, Raymond Pagliarini, Nicholas Keen, Tobias Schmelzle, Francesco Hofmann, Frank Stegmeier, William R. Sellers. Disordered methionine metabolism in MTAP/CDKN2A-deleted cancers leads to marked dependence on PRMT5. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-017.

Critical Role of Central Facilitation in the Glottic Closure Reflex

The sphincteric function of the larynx, essential to lower airway protection, is most efficiently achieved through strong reflex adduction by both vocal cords. We hypothesize that central facilitation is an essential component of a bilateral adductor reflex and that its disturbance could result in weakened sphincteric closure. Six adult 50-kg pigs underwent evoked response laryngeal electromyography under 0.5 to 1.0 minimal alveolar concentration (MAC) isoflurane anesthesia. The internal branch of the superior laryngeal nerve was stimulated through bipolar platinum-iridium electrodes, and recording electrodes were positioned in the ipsilateral and contralateral thyroarytenoid muscles. Consistent threshold responses were obtained ipsilaterally from 0.5 to 1.0 MAC anesthesia. However, the contralateral reflex responses approached 0% in successive trials as anesthetic levels approached 1.0 MAC. Alteration of central facilitation by deepening anesthesia abolishes the crossed adductor reflex, predisposing to a weakened glottic closure response. A precise understanding of this effect may improve the prevention of aspiration in patients emerging from prolonged sedation or under heavy psychotropic control.

Bioengineering bacteriophages to enhance the sensitivity of phage amplification-based paper fluidic detection of bacteria

Bacteriophage (phage) amplification is an attractive method for the detection of bacteria due to a narrow phage-host specificity, short amplification times, and the phages' ability to differentiate between viable and non-viable bacterial cells. The next step in phage-based bacteria detection is leveraging bioengineered phages to create low-cost, rapid, and easy-to-use detection platforms such as lateral flow assays. Our work establishes the proof-of-concept for the use of bioengineered T7 phage strains to increase the sensitivity of phage amplification-based lateral flow assays. We have demonstrated a greater than 10-fold increase in sensitivity using a phage-based protein reporter, maltose-binding protein, over the detection of replicated T7 phage viron itself, and a greater then 100-fold increase in sensitivity using a phage-based enzymatic reporter, alkaline phosphatase. This increase in sensitivity enabled us to detect 10(3)CFU/mL of Escherichia coli in broth after 7h, and by adding a filter concentration step, the ability to detect a regulatory relevant E. coli concentration of 100CFU/100mL in inoculated river water after 9h, where the current standard requires days for results. The combination of the paper fluidic format with phage-based detection provides a platform for the development of novel diagnostics that are sensitive, rapid, and easy to use.