Effect of Interval between Neoadjuvant Chemotherapy and Radiation Therapy on Metastasis Risk for Inoperable Non-Metastatic Pancreatic Adenocarcinoma

PURPOSE/OBJECTIVE(S)

In inoperable pancreatic cancer patients requiring radiotherapy (RT) after neoadjuvant chemotherapy (CT), there can be delays in starting radiation due to multiple complications. However, pancreatic cancer can progress rapidly during short intervals without treatment. We hypothesize that longer intervals between neoadjuvant chemotherapy and radiation could expediate the development of metastatic disease.

MATERIALS/METHODS

We identified patients with inoperable non-metastatic borderline resectable or locally advanced pancreatic cancer treated with neoadjuvant CT followed by RT from 2011 to 2021 at a single institution. Patients who completed palliative RT as defined by a biologic effective dose (BED) of less than 50 Gy, or those who were lost to follow-up within 3 months after completing RT without documented disease progression were excluded. The interval between RT and CT was defined as the time between last date of CT administration and initiation of RT. The primary endpoint was metastasis-free survival (MFS) after RT completion. Differences in MFS between patients who started RT within or after 4, 6, and 8 weeks of completing CT were examined utilizing log rank analysis of MFS generated via the Kaplan-Meier method.

RESULTS

At a median follow-up of 5.45 months, twenty-three patients were included. Most patients were male (61%) with cT4 (61%), cN0 (83%) pancreatic adenocarcinoma. Almost all patients completed combination neoadjuvant CT (91%) followed by either intensity modulated RT to 50.4 Gy in 28 fractions with capecitabine (n = 9) or stereotactic body RT to 33-40 Gy in 5 fractions (n = 14). Eleven (48%) patients received adjuvant CT after radiation therapy. The median time between last CT and RT initiation was 34 days (range 13-142). The MFS of patients who initiated RT within 4 weeks of CT compared to after was higher but not significant (16.8 vs 9.9 months, p = 0.144). Those who received RT within 6 or 8 weeks of completing CT exhibited significantly longer MFS compared to later than 6 (16.0 vs 6.9 mo, p = 0.016) or 8 weeks (15.1 vs 2.1 mo, p = 0.004). There was no statistical correlation between MFS and other variables (CA 19-9 before radiation, T-stage, receipt of adjuvant CT, BED).

CONCLUSION

These results suggest that a longer interval between CT and RT is associated with the risk of developing metastatic disease sooner but requires validation in a prospective cohort. Root causes of delays in starting radiation (e.g., insurance authorization) should be investigated as well.

Automated deep learning quantification of epicardial adiposity on cardiac CT predicts atrial fibrillation risk immediately following cardiac surgery and long-term

Introduction

Epicardial adipose tissue (EAT) is a visceral fat deposit within the pericardial sac which surrounds the heart myocardium and coronary arteries. The automated quantification of EAT volume is possible from routine CCTA scans via a deep-learning approach. The use of automated EAT quantification for the assessment of atrial fibrillation (AF) risk in the post-operative period, and longer-term, has not been previously investigated.

Purpose

To apply a deep-learning approach for automated segmentation of EAT from routine CCTA scans to assess the immediate post-operative and long-term risk of AF conveyed by EAT.

Methods

A deep-learning automated EAT segmentation tool using a 3D Residual-U-Net neural network architecture for 3D volumetric segmentation of CCTA data was created and trained on over 2800 consecutive CCTA performed as part of clinical care in patients with stable chest pain from 2015 onwards within the European arm of the Oxford Risk Factors And Non Invasive Imaging (ORFAN) Study. External validation in 817patients demonstrated excellent correlation between machine and human expert (CCC = 0.972). The prognostic value of deep-learning derived EAT volume was assessed in the AdipoRedOx Study (n=253; UK patients undergoing cardiac surgery) against both immediate in-hospital outcomes and longer-term outcomes from UK-wide NHS data, with adjustment for AF risk factors.

Results

There were 97 cases of new-onset AF in the immediate post-operative period (38.3%). EAT volume was found to be an independent predictor of post-operative AF regardless of body mass index. Utilising the median EAT volume as the cut point, the adjusted hazard ratio (HR [95% CI]) for risk of new-onset post-operative AF in-hospital was 1.56 [1.09–3.85], p<0.01 (Figure 1A). In receiver-operator characteristic analysis EAT volume added significant incremental prognostic power for the discrimination of in-hospital post-operative AF over a traditional risk factor model ΔAUC=0.101, p<0.01 (Figure 1B).

Over a median follow-up period of 89 months there were 48 unique cases (19%) of confirmed AF found in nation-wide NHS hospital episode statistics data for the AdipoRedOx cohort. EAT volume was found to be a significant independent predictor of long-term AF. Utilising the median EAT volume as the cut point, the adjusted HR for risk of new-onset long-term AF following cardiac surgery was 1.25 [1.08–3.17], p<0.01 (Figure 1C).

Conclusions

Automatically segmented EAT volume measured using a deep learning network predicts risk of both short-term new onset AF following cardiac surgery, and long-term risk of AF in the 7 years following the surgery independently of BMI and AF risk factors. This suggests that EAT is a potent mediator of AF risk in the post cardiac surgery setting.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation - TG/19/2/34831EU Commission - 965286

Predictors of acute pulmonary embolism-related hospitalizations – an artificial neural network analysis using a nationwide cohort in the United States

Background

Considering a paucity of large-scale data on predictors of pulmonary embolism (PE) and its higher association with complications and worse outcomes, we aimed to determine the predictors of PE in this United States population-based analysis using Artificial Neural Network (ANN) Model in a nationally representative cohort.

Methods

We identified PE-related hospitalizations using 2018's National Inpatient Sample database. The relevant predictive factors for ANN were selected for this cohort. Of all admissions (unweighted n=7,105,498, weighted n=35,527,481), PE cohort (weighted n=387805) consisted of 1.1% of all admissions in 2018. The 2018 cohort was randomly split into training data (unweighted n=4716132, 70.0%) which were used to calibrate ANN and testing data (unweighted n=2019290, 30%) which were used to assess the accurateness of the algorithm. We equated the rate of incorrect prediction between training and testing data and measured the Area under Receiver Operator Curve (AUC) to determine ANN's efficacy in predicting PE hospitalizations.

Results

Patients hospitalized with PE often consisted of older (mean age 62.5±17.1 years), female (51.3%), white (70.5%) patients, and patients from lower-income quartile (0–25% income quartile: 28.8%%), often admitted non-electively (93.7%) with higher rates of cardiovascular disease risk factors. PE admissions revealed significantly higher (6.5% vs. 1.9%, p<0.001) in-hospital mortality, less frequent routine discharges (51.4% vs. 68.1%) and more frequent other facility transfers and requirement of home health care. Normalized Predictors of PE admissions are displayed in Fig. 1. Our ANN model had AUC 0.873 which correlates with an excellent prediction model. Our data demonstrated low levels (0.8%) error in both testing and training models.

Conclusion

Our ANN model showed high performance to predict risk factors for PE admissions in the US population. It will enable clinicians to screen patients at high-risk for PE admissions, curtail complication rate, improve survival and lower the healthcare cost.

Funding Acknowledgement

Type of funding sources: None.

Cardiovascular disease risk factors and outcomes of acute myocardial infarction in young adults in two nationwide cohorts in the united states

Funding Acknowledgements

Type of funding sources: None.

Background

Acute myocardial infarction (AMI) can have considerable morbidity and devastating socioeconomic and psychological consequences in young adults. Previous studies reveal that the decline in mortality in AMI has mainly been in the older population while being comparatively less significant in younger patients. This study compares young adults (18 to 44 years) hospitalized with AMI across two nationwide cohorts, 2007 and 2017, in the United States (US). It examines the burden of AMI hospitalizations, the prevalence of comorbidities, and in-hospital outcomes in young adults a decade apart. It highlights the rise in AMI hospitalizations, lack of decrease in mortality, sex-based and racial disparities, the surge in post-MI complications, and the decline in reperfusion interventions in young AMI patients over a decade.

Purpose

Coronary heart disease prevalence is challenging to ascertain in younger adults because of limited data and frequent silent clinical presentations. AMI and its complications can cause considerable morbidity, psychological trauma, and socioeconomic burden in the young.

Methods

We identified hospitalizations for AMI in young adults in 2007 and 2017 using the weighted data from the National Inpatient Sample (NIS), which covers 20% of stratified data of all non-federal community hospitals in the US. We compared the following data between the two cohorts: admission rates, sociodemographic features, in-hospital morbidity, complications, mortality, rate of coronary interventions, and healthcare utilization between the two cohorts. We used Pearson’s Chi-square test and Mann-Whitney U test to compare categorical and continuous variables, respectively. We also applied multivariable regression analyses to assess and compare the risk of cardiovascular complications and in-hospital mortality while controlling for confounders, including age, sex, race, median household income quartile, primary insurance enrolment, and pre-existing comorbidities.

Results

AMI’s incidence was higher in males in both the cohorts, although with a decline (71.1% vs 66.1%), whereas it rose from 28.9% to 33.9% in females. Hypertension (47.8% vs 60.7%), smoking (49.7% vs 55.8%), obesity (14.8% vs 26.8%), and diabetes mellitus (22.0% vs 25.6%) increased in the 2017 cohort (Table 1). We found no significant difference in all-cause mortality (aOR = 1.01 (0.93-1.10), p=0.749). Post-AMI complications, cardiogenic shock (aOR = 1.16 (1.06-1.27), p=0.001), and fatal arrhythmias increased. Reperfusion interventions decreased in the 2017 cohort (PCI; aOR=0.95 (0.91-0.98), p<0.001; CABG; aOR=0.66 (0.61-0.71), p<0.001) (Table 2).

Conclusion

Our study highlights the rise in AMI hospitalizations, plateauing of mortality, gender disparity, the surge in post-MI complications, and a reassuring decline in the requirement of reperfusion interventions in young AMI patients over a decade.

Frequency, risk and predictors of type 2 myocardial infarction hospitalizations in young obese patients: A nationwide population-based analysis in the United States

Funding Acknowledgements

Type of funding sources: None.

Background

Obesity in the young population is emerging as a challenging health concern. Though there is a rising prevalence of obesity and its potential association with demand ischemia-related myocardial infarction, data remains non-existent to evaluate the association of obesity or higher body mass index (BMI) with type 2 myocardial infarction (T2MI). We aim to identify the frequency, risk and predictors of T2MI in young hospitalized obese patients compared to non-obese patients in this population-based study.

Methods

We used National Inpatient Sample (2018, ICD-10 codes) to identify T2MI in young (18-44 years) hospitalized patients. Obesity was identified from comorbidities or using diagnostic codes for BMI>30 kg/m2. We performed multivariable regression analysis for the primary outcome of odds of T2MI in young obese patients compared to non-obese patients. The frequency of T2MI was compared between obese vs non-obese patients in overall and subgroup populations. Sociodemographic characteristics and comorbidities in T2MI-obese vs. T2MI-non-obese cohorts were also compared. A p<0.05 was considered a threshold for statistical significance.

Results

Out of 1,268,255 young hospitalized patients with obesity, 555 had T2MI. T2MI was significantly higher in young obese than non-obese (44 T2MI/100000 hospitalizations in young obese patients vs. 17 T2MI/100000 hospitalizations in young non-obese patients, overall 0.04% in obese vs. 0.02% in non-obese, p<0.001). Multivariate analysis revealed higher odds of T2MI in obese than nonobese when adjusted for demographics (aOR 2.65, 95% CI:2.42-2.90, p<0.001) and social demographics with comorbidities (aOR 1.60, 95% CI:1.24-2.07, p<0.001). In young obese, higher risk was found with advancing age (OR 1.07, 95% CI 1.03-1.11, p=0.001), in males than females (aOR 2.70, p<0.001), and blacks (aOR 2.22, p=0.011) and Native Americans (OR 3.91, 95% CI: 1.13-13.49, p=0.011) vs whites. Comorbidities including chronic obstructive pulmonary disease (OR 1.86), chronic kidney disease (CKD, OR 2.36), rheumatoid arthritis/collagen vascular disease (RA/CVD, OR 3.04) Iin young obese patients independently increased the risk of T2MI hospitalizations [Table 1]. The T2MI-obese cohort had a significantly higher rate of hyperlipidemia, hypertension, diabetes, COPD, and prior history of MI and TIA/stroke compared to the T2MI-nonobese cohort [Table 2].

Conclusion

This nationwide analysis revealed a significantly higher risk of T2MI in young obese patients compared to nonobese after excluding patients with concomitant diagnoses of T1MI. Males, blacks compared to females and whites, and comorbidities including COPD, CKD and RA/CVD predicted a higher risk of T2MI in young obese patients. Future studies are warranted to evaluate the role of higher body mass index in myocardial oxygen demand-supply mismatch and short-term/long-term risk and outcomes of T2MI.

Nationwide frequency, risk and outcomes of type-2 myocardial infarction in patients with versus without previously revascularized myocardial infarction (type 1)

Funding Acknowledgements

Type of funding sources: None.

Background

Type 2 myocardial infarction (T2MI), due to a mismatch between myocardial oxygen demand and supply, is being increasingly recognized with improved diagnostics. The upsetting concern of developing T2MI in patients with prior revascularized occlusive acute myocardial infarction (AMI) or type 1 MI (T1MI) makes it crucial to define the clinical profile and outcomes of T2MI in revascularized patients of ACS.

Purpose

To determine the risk and prognosis of T2MI in patients who had previously had coronary revascularization (PCI or CABG)

Methods

We used the National Inpatient Sample (2018) dataset from the United States to identify T2MI adult hospitalizations using ICD-10 codes and define our study arm as T2MI excluding secondary T1MI diagnoses but having prior revascularized (with percutaneous coronary intervention or coronary artery bypass grafting) AMI. We then compared demographics and comorbidities in T2MI cohort with vs without personal history of revascularized AMI. We used multivariate analysis to study the odds of T2MI hospitalizations with prior revascularized AMI and in-hospital outcomes (all-cause mortality, cardiogenic shock and resource utilization) adjusting for confounders.

Results

There were 33155 T2MI adult hospitalizations after excluding AMI (median age 71 years, 50.6% male, 67.3% white); 1435 (4.3%) had previously revascularized AMI. T2MI in the study arm had higher chances of hospitalization with prior revascularized AMI when adjusted for socio-demographics (aOR 6.92, 95% CI:6.50-7.36, p<0.001) and socio-demographics with comorbidities (aOR 5.70, 95%CI: 5.48-5.94, p<0.001) (Table 1). Study arm often had elderly (≥65 years old, 78.4% vs 65.8%), male (66.6% vs 49.9%), white (76.7% vs 66.9%), upper socio-economic class (20.2 vs 16.8%), patients who were often admitted to non-electively (99.3 vs 97.1%) and to rural (10.5 vs 9.3%) hospitalizations compared to control arm. The study arm had a significantly higher prevalence of diabetes mellitus, hyperlipidemia, peripheral vascular disease, chronic obstructive pulmonary disease, renal failure, deficiency anemias, prior TIA/stroke, depression and smoking. T2MI cohort with prior revascularized AMI did not show any significant association with in-hospital all-cause mortality (1.7 vs 3.0%, aOR 0.49, 95%CI 0.18-1.34, p=0.164) and cardiogenic shock (1.7% vs 2.1%, p=0.399) however, had lower hospital expenditure (median USD 31273 vs 36567) and fewer transfers to other facilities (19.5 vs 22.1%) than those without prior revascularized AMI (Table 2).

Conclusion

Population-based analysis of this nationally representative sample revealed up to six times higher risk of developing T2MI in patients with prior history of AMI (revascularized) but without any significant impact on all-cause in-hospital mortality or cardiogenic shock. Future studies are warranted to assess the short-term/long-term outcomes of T2MI in high risk patient population with previously revascularized AMI.

Clinical trial management: a profession in crisis?

Clinical trial managers play a vital role in the design and conduct of clinical trials in the UK. There is a current recruitment and retention crisis for this specialist role due to a complex set of factors, most likely to have come to a head due to the COVID-19 pandemic. Academic clinical trial units and departments are struggling to recruit trial managers to vacant positions, and multiple influences are affecting the retention of this highly skilled workforce. Without tackling this issue, we face major challenges in the delivery on the Department of Health and Social Care's Future of UK Clinical Research Delivery implementation plan. This article, led by a leading network of and for UK Trial Managers, presents some of the issues and ways in which national stakeholders may be able to address this.

Differential assembly diversifies GABAA receptor structures and signalling

Type A γ-aminobutyric acid receptors (GABAARs) are pentameric ligand-gated chloride channels that mediate fast inhibitory signalling in neural circuits1,2 and can be modulated by essential medicines including general anaesthetics and benzodiazepines3. Human GABAAR subunits are encoded by 19 paralogous genes that can, in theory, give rise to 495,235 receptor types. However, the principles that govern the formation of pentamers, the permutational landscape of receptors that may emerge from a subunit set and the effect that this has on GABAergic signalling remain largely unknown. Here we use cryogenic electron microscopy to determine the structures of extrasynaptic GABAARs assembled from α4, β3 and δ subunits, and their counterparts incorporating γ2 instead of δ subunits. In each case, we identified two receptor subtypes with distinct stoichiometries and arrangements, all four differing from those previously observed for synaptic, α1-containing receptors4-7. This, in turn, affects receptor responses to physiological and synthetic modulators by creating or eliminating ligand-binding sites at subunit interfaces. We provide structural and functional evidence that selected GABAAR arrangements can act as coincidence detectors, simultaneously responding to two neurotransmitters: GABA and histamine. Using assembly simulations and single-cell RNA sequencing data8,9, we calculated the upper bounds for receptor diversity in recombinant systems and in vivo. We propose that differential assembly is a pervasive mechanism for regulating the physiology and pharmacology of GABAARs.

Jewish cultural and religious factors and uptake of population-based BRCA testing across denominations: a cohort study

OBJECTIVE

To evaluate the association of Jewish cultural and religious identity and denominational affiliation with interest in, intention to undertake and uptake of population-based BRCA (Breast Cancer Gene)-testing.

DESIGN

Cohort-study set within recruitment to GCaPPS-trial (ISRCTN73338115).

SETTING

London Ashkenazi-Jewish (AJ) population.

POPULATION OR SAMPLE

AJ men and women, >18 years.

METHODS

Participants were self-referred, and attended recruitment clinics (clusters) for pre-test counselling. Subsequently consenting individuals underwent BRCA testing. Participants self-identified to one Jewish denomination: Conservative/Liberal/Reform/Traditional/Orthodox/Unaffiliated. Validated scales measured Jewish Cultural-Identity (JI) and Jewish Religious-identity (JR). Four-item Likert-scales analysed initial 'interest' and 'intention to test' pre-counselling. Item-Response-Theory and graded-response models, modelled responses to JI and JR scales. Ordered/multinomial logistic regression modelling evaluated association of JI-scale, JR-scale and Jewish Denominational affiliation on interest, intention and uptake of BRCA testing.

MAIN OUTCOME MEASURES

Interest, intention, uptake of BRCA testing.

RESULTS

In all, 935 AJ women/men of mean age = 53.8 (S.D = 15.02) years, received pre-test education and counselling through 256 recruitment clinic clusters (median cluster size = 3). Denominational affiliations included Conservative/Masorti = 91 (10.2%); Liberal = 82 (9.2%), Reform = 135 (15.1%), Traditional = 212 (23.7%), Orthodox = 239 (26.7%); and Unaffiliated/Non-practising = 135 (15.1%). Overall BRCA testing uptake was 88%. Pre-counselling, 96% expressed interest and 60% intention to test. JI and JR scores were highest for Orthodox, followed by Conservative/Masorti, Traditional, Reform, Liberal and Unaffiliated Jewish denominations. Regression modelling showed no significant association between overall Jewish Cultural or Religious Identity with either interest, intention or uptake of BRCA testing. Interest, intention and uptake of BRCA testing was not significantly associated with denominational affiliation.

CONCLUSIONS

Jewish religious/cultural identity and denominational affiliation do not appear to influence interest, intention or uptake of population-based BRCA testing. BRCA testing was robust across all Jewish denominations.

TWEETABLE ABSTRACT

Jewish cultural/religious factors do not affect BRCA testing, with robust uptake seen across all denominational affiliations.

Automated quantification of epicardial adipose tissue on CCTA via deep-learning detection of the pericardium: clinical implications

Background

Epicardial adipose tissue (EAT) is a visceral fat deposit within the pericardial sac which surrounds the heart myocardium and coronary arteries. EAT volume has been demonstrated to be strongly associated with the development and prognosis of cardiovascular diseases, but its measurement is subjective and challenging in practice.

Purpose

To develop a deep-learning approach for automated segmentation of EAT from routine CCTA scans, that could assist clinical interpretation of CCTA.

Methods

A deep-learning method using a 3D Residual-U-Net neural network architecture for 3D volumetric segmentation of CCTA data was created. The network was trained on a diverse sample of 1900 CCTAs, each manually segmented by a single expert, drawn from the UK sites of the Oxford Risk Factors And Non-invasive imaging (ORFAN) Study. Three iterations of feedback learning were used to fine tune the algorithm for the segmentation of the whole heart within the bounds of the pericardium. In each iteration, the machine analysed sets of 100–250 unannotated CCTAs unseen by the machine which were then corrected by experts. EAT volumes were calculated by automated thresholding of adipose tissue (−190HU through −30HU) from within the bound of the pericardial segment (Figure 1). The network was then applied to 817 unseen CCTAs from US sites of the ORFAN Study. These scans were also segmented for ground truth by two experts blind to all other data. Comparisons between machine vs expert total pericardial volume and EAT volume were made using Lin's concordance correlation coefficient (CCC). The algorithm was then applied externally in 1588 CCTAs from the SCOTHEART trial (UK), and the EAT volume was automatically calculated for each case. Cross-sectional associations between standardised EAT volumes and prevalent AF and CAD were performed.

Results

Within both the internal (UK ORFAN sites) and external (USA ORFAN sites) validation cohorts correlation between human and machine segmented total pericardium and EAT was excellent, with CCC of 0.97 for both volumes (external validation cohort shown in Figure 2A). Utilising SCOTHEART CCTAs with automatically segmented EAT volumes, a multivariable-adjusted logistic regression model accounting for risk factors of age, sex, BMI, hypertension, diabetes mellitus, valvular disease, and previous heart surgery found that EAT volumes were significantly associated with prevalent AF, with odds ratio (OR) per 1 SD increase of EAT volume of 1.20 (95% CI, 1.06 to 1.44; P=0.03). A similar model for prevalent CAD, adjusted for age, sex, BMI, hypertension, non-HDL cholesterol, diabetes mellitus, and coronary artery calcium score resulted in an OR per 1 SD increase of EAT volume of 1.26 (95% CI, 1.10 to 1.45; P=0.001) (Figure 2B).

Conclusion

Highly accurate, reproducible, and instantaneous EAT volume quantification is possible utilising deep-learning detection of the whole human heart within the pericardial sac.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): British Heart FoundationNational Institute for Health Research - Oxford University Hospitals Biomedical Research Centre Figure 1Figure 2

Pulmonary artery injury in left atrial appendage closure device implantation: a systematic review of a potentially fatal complication

Background

Pulmonary artery (PA) injury is a rarely reported complication following percutaneous left atrial appendage closure (LAAC). This study aims to systematically review all reported cases of PA injury associated with LAAC.

Methods

PubMed/Medline, SCOPUS, EMBASE, Google Scholar and the MAUDE databases were searched to find studies reporting PA injury during or after LAAC with the Amplatzer Amulet (AA), Amplatzer Cardiac Plug (ACP) or Watchman device through October 2019. Categorical data were reported in terms of numbers and/or percentages (%).

Results

We found 13 cases (mean age 71.4 yrs) with reported PA injury associated with LAAC. Of these, 9 were case reports, 3 were reported in observational studies, and 1 was in the MAUDE database. Most cases (n=8) were reported in Europe followed by Australia (n=2) and Asia (n=2). The indication for device implantation in all patients was a high bleeding risk with anticoagulation for atrial fibrillation. Five cases were reported with the ACP (1/5 patients died), 5 with AA (2/5 patients died), and 3 with the Watchman (1/2 patients died). Acute and late presentations following implantation were reported for all three devices. 69.2% of cases (9/13) occurred acutely (during or within 24 hours of intervention). Of these, 3/9 occurred during device implantation. 2/4 of the delayed cases occurred >2 weeks following implantation. The mortality rate for acute and delayed cases was 22% (2/9 patients) and 50% (2/4 patients), respectively. A majority of the cases were attributable to barb/strut/hook injury of the PA. PA injury was associated with a mortality rate of approximately 31%. All surviving patients were managed with surgical intervention.

Conclusion

PA injury is an infrequently reported complication following LAAC and is associated with high mortality. Cases can present acutely (intra-procedurally or within 24 hours) or delayed (>24 hours post-implantation). A majority of cases are due to direct injury of the PA by the struts/hooks/barbs of the device. Practitioners should be cognizant of this life-threatening complication, which requires a high index of suspicion for diagnosis and can occur weeks after device implantation.

Funding Acknowledgement

Type of funding source: None

Rates and causes of readmissions following index admissions for Takotsubo syndrome-a meta-analysis of 118,941 index hospitalizations

Background

Rising trends in takotsubo syndrome (TTS)-related complications warrant data to identify the rate, causes and predictors of readmission on a large scale. We conducted the first-ever meta-analysis to evaluate the pooled rate of short-term and long-term readmissions after index TTS admissions.

Methods

PubMed/Medline, EMBASE and SCOPUS databases were systematically reviewed to find studies through October 2019 reporting rates and causes of readmission following index TTS admissions. Random effects models were used to estimate pooled rates and causes of readmissions and I2 statistics were used to report inter-study heterogeneity.

Results

A total of 16 cohorts with 118,941 TTS index admissions (mean age 65–75 yrs; female >85%, median follow-up 272.5 days) revealed a 16.6% [95% CI-13.2%-20.3%, I2=99%] pooled rate of readmission. Short-term and long-term pooled readmission rates are displayed in Fig.1. The readmission rate was higher in cohorts with young patients (<70 vs. >70 yrs), smaller sample size (n<100 vs. n>100) and single-centres vs. multicentres. Studies published from the USA (16.4% vs. 14.9%) had a higher readmission rate as compared to Italy. The most frequent causes were cardiac (40.6%), respiratory (15.7%) and renal (7.0%). Among readmissions with cardiac diagnoses, heart failure was most common (40.1%).

Conclusions

This global meta-analysis revealed that the pooled rate of readmission following index TTS admissions was ∼17% and causes were mainly cardiac or respiratory.

Funding Acknowledgement

Type of funding source: None

Prioritising health research in KwaZulu-Natal: has the research conducted met the research needs?

Background

The KwaZulu-Natal (KZN) Health Act of 2009 mandates the Provincial Health Research and Ethics Committee to develop health research priorities for the province. During 2013, the KZN Department of Health embarked on a research prioritisation process for the province. Priority research questions were generated by an inclusive process, in which a variety of stakeholders in health research in the province were engaged. The aim of this study was to determine whether research conducted at public health facilities in KZN between 01 January 2014 and 31 March 2017 met the research priorities of the province developed through the provincial research prioritisation process of 2013.

Methods

This was a mixed methods study. Qualitative thematic analysis was used to categorise priority research questions generated in the priority-setting process and the titles of research projects conducted after that process into themes. Quantitative analysis was used to determine the correlation between themes of the priority questions, and those of the research projects conducted after the prioritisation exercise. Statistical Package for Social Science version 25 was used to analyse the data.

Results

In 72% of thematic areas, there were disproportionately more priority questions than there were research projects conducted. There is thus a large disjuncture between the priorities developed through the provincial research prioritisation process of 2013 and the research projects conducted after that process in terms of major research areas.

Conclusions

Ensuring that research conducted responds to priority questions raised is important because it ensures that research responds to locally important issues and to the concerns of local actors. Local health managers, communities and researchers should work together to ensure that the research conducted in their areas respond to the research priorities of those areas. Health Research Committees and local ethics committees can play important roles in facilitating the responsiveness to research priorities.

Circulating Sex Steroid Measurements of Men by Mass Spectrometry Are Highly Reproducible after Prolonged Frozen Storage

Long-term studies investigating hormone-dependent cancers and reproductive health often require prolonged frozen storage of serum which assumes that the steroid molecules and measurements are stable over that time. Previous studies of reproducibility of circulating steroids have relied upon flawed historical rather than contemporaneous controls. We measured serum testosterone (T), dihydrotestosterone (DHT), estradiol (E2) and estrone (E1) in 150 randomly selected serum samples by liquid chromatography-mass spectrometry (LC-MS) from men 70 years or older (mean age 77 years) in the CHAMP study. The original measurements in 2009 were repeated 10 years later using the identical serum aliquot (having undergone 2-4 freeze-thaw cycles in the interim) in 2019 together with another never-thawed aliquot of the same serum sample. The results of all three sets of measurements were evaluated by Passing-Bablok regression and Bland-Altman difference analysis. Serum androgens (T, DHT) and estrogens (E2, E1) measured by LC-MS display excellent reproducibility when stored for 10 years at -80 C without thawing. Serum T and DHT displayed high level of reproducibility across all three sets of measurements. Multiple freeze-thaw cycles over those storage conditions do not significantly affect serum T, DHT and E1 concentrations but produce a modest increase (21%) in serum E2 measurements.

Tackling smoking among out of school youth in South Africa: An analysis of friendship ties

Background

Friendships during adolescence play a significant role in the initiation and maintenance of tobacco use. Smoking behaviour among adolescent friends has not been explored among out of school youth (OSY) in South Africa. Out of school youth (OSY), described as those between 13 and 20 years old, have not completed their schooling and are not currently enrolled in school, are at greater risk for tobacco use.

Aim

The main aim of this study is to examine whether the smoking behaviour of OSY is associated with that of their OSY friends.

Methods

Respondent driven sampling was used to recruit OSY and their OSY friends. A mixed effects logistic regression with a random intercept across school-province combinations was used to analyse survey data. Race and gender were also incorporated into the analyses as effect moderators (n = 391).

Results

Results of this study confirm that cigarette smoking was common among OSY and their OSY friends, with 53.5% of the respondents smoking in the past month (SD = 0.44). When OSY friends were either all non-smokers or half their friends were non-smokers, Coloured (mixed race) OSY were less likely to smoke compared to Black African and Other (mostly Asian descent) OSY.

Conclusion

Cultural norms and values associated with the different race groups may play a role in the smoking behaviour of out of school youth friends. Understanding this relationship is useful for identifying those OSY that are vulnerable to the behaviours that place them at risk of tobacco related morbidity and mortality.

•

Smoking was common among out of school youth and their out of school youth friends.

•

Racial differences were found in out of school youth smoking and their friends.

•

Cultural norms and values influence smoking behaviour of out of school youth friends.

Attitude towards and factors affecting uptake of population-based BRCA testing in the Ashkenazi Jewish population: a cohort study

OBJECTIVE

To evaluate factors affecting unselected population-based BRCA testing in Ashkenazi Jews (AJ).

DESIGN

Cohort-study set within recruitment to the GCaPPS trial (ISRCTN73338115).

SETTING

North London AJ population.

POPULATION OR SAMPLE

Ashkenazi Jews women/men >18 years, recruited through self-referral.

METHODS

Ashkenazi Jews women/men underwent pre-test counselling for BRCA testing through recruitment clinics (clusters). Consenting individuals provided blood samples for BRCA testing. Data were collected on socio-demographic/family history/knowledge/psychological well-being along with benefits/risks/cultural influences (18-item questionnaire measuring 'attitude'). Four-item Likert-scales analysed initial 'interest' and 'intention-to-test' pre-counselling. Uni- and multivariable logistic regression models evaluated factors affecting uptake/interest/intention to undergo BRCA testing. Statistical inference was based on cluster robust standard errors and joint Wald tests for significance. Item-Response Theory and graded-response models modelled responses to 18-item questionnaire.

MAIN OUTCOME MEASURES

Interest, intention, uptake, attitude towards BRCA testing.

RESULTS

A total of 935 individuals (women = 67%/men = 33%; mean age = 53.8 (SD = 15.02) years) underwent pre-test genetic-counselling. During the pre-counselling, 96% expressed interest in and 60% indicated a clear intention to undergo BRCA testing. Subsequently, 88% opted for BRCA testing. BRCA-related knowledge (P = 0.013) and degree-level education (P = 0.01) were positively and negatively (respectively) associated with intention-to-test. Being married/cohabiting had four-fold higher odds for BRCA testing uptake (P = 0.009). Perceived benefits were associated with higher pre-counselling odds for interest in and intention to undergo BRCA testing. Reduced uncertainty/reassurance were the most important factors contributing to decision-making. Increased importance/concern towards risks/limitations (confidentiality/insurance/emotional impact/inability to prevent cancer/marriage ability/ethnic focus/stigmatisation) were significantly associated with lower odds of uptake of BRCA testing, and discriminated between acceptors and decliners. Male gender/degree-level education (P = 0.001) had weaker correlations, whereas having children showed stronger (P = 0.005) associations with attitudes towards BRCA testing.

CONCLUSIONS

BRCA testing in the AJ population has high acceptability. Pre-test counselling increases awareness of disadvantages/limitations of BRCA testing, influencing final cost-benefit perception and decision-making on undergoing testing.

TWEETABLE ABSTRACT

BRCA testing in Ashkenazi Jews has high acceptability and uptake. Pre-test counselling facilitates informed decision-making.

Author Correction: GABAA receptor signalling mechanisms revealed by structural pharmacology

In Fig. 5b, d, the arrows showing transmembrane domain rotations were inadvertently pointing clockwise instead of anticlockwise. Similarly, 'anticlockwise' should have been 'clockwise' in the sentence 'This conformational change of the ECD triggers a clockwise rotation of the TMD.' In Extended Data Table 1, the units of the column 'Model resolution' should have been Šinstead of Ų. These errors have been corrected online.

GABAA receptor signalling mechanisms revealed by structural pharmacology

Type-A γ-aminobutyric (GABAA) receptors are ligand-gated chloride channels with a very rich pharmacology. Some of their modulators, including benzodiazepines and general anaesthetics, are among the most successful drugs in clinical use and are common substances of abuse. Without reliable structural data, the mechanistic basis for the pharmacological modulation of GABAA receptors remains largely unknown. Here we report several high-resolution cryo-electron microscopy structures in which the full-length human α1β3γ2L GABAA receptor in lipid nanodiscs is bound to the channel-blocker picrotoxin, the competitive antagonist bicuculline, the agonist GABA (γ-aminobutyric acid), and the classical benzodiazepines alprazolam and diazepam. We describe the binding modes and mechanistic effects of these ligands, the closed and desensitized states of the GABAA receptor gating cycle, and the basis for allosteric coupling between the extracellular, agonist-binding region and the transmembrane, pore-forming region. This work provides a structural framework in which to integrate previous physiology and pharmacology research and a rational basis for the development of GABAA receptor modulators.

Neonatal hyperlipidemia with pancreatitis: Novel gene mutation of lipoprotein lipase

Lipoprotein lipase (LPL) deficiency is an autosomal recessive metabolic disorder with varying presentation in infancy and childhood, whereas clinical manifestations are rare in neonatal period. The estimated prevalence is one in a million births. A 23-day-old baby was admitted with complaints of fever, vomiting, and lethargy. Blood sample drawn appeared lipemic. Lipemia retinalis was noted on funduscopic examination. Biochemical analysis revealed abnormal lipid profile with severe hypertriglyceridemia (10,300 mg/dL) and elevated serum lipase level (517 IU/L) indicative of LPL deficiency with acute pancreatitis. LPL deficiency was suspected and was confirmed by molecular genetic testing, which revealed a novel mutation in LPL gene. Dietary management and gemfibrozil were started following which serum triglyceride level decreased and serum lipase level normalized. The patient is following up regularly for growth and development monitoring.

Positive reinforcement targeting abstinence in substance misuse (PRAISe): Study protocol for a Cluster RCT & process evaluation of contingency management

There are approximately 256,000 heroin and other opiate users in England of whom 155,000 are in treatment for heroin (or opiate) addiction. The majority of people in treatment receive opiate substitution treatment (OST) (methadone and buprenorphine). However, OST suffers from high attrition and persistent heroin use even whilst in treatment. Contingency management (CM) is a psychological intervention based on the principles of operant conditioning. It is delivered as an adjunct to existing evidence based treatments to amplify patient benefit and involves the systematic application of positive reinforcement (financial or material incentives) to promote behaviours consistent with treatment goals. With an international evidence base for CM, NICE recommended that CM be implemented in UK drug treatment settings alongside OST to target attendance and the reduction of illicit drug use. While there was a growing evidence base for CM, there had been no examination of its delivery in UK NHS addiction services. The PRAISe trial evaluates the feasibility, acceptability, clinical and cost effectiveness of CM in UK addiction services. It is a cluster randomised controlled effectiveness trial of CM (praise and financial incentives) targeted at either abstinence from opiates or attendance at treatment sessions versus no CM among individuals receiving OST. The trial includes an economic evaluation which explores the relative costs and cost effectiveness of the two CM intervention strategies compared to TAU and an embedded process evaluation to identify contextual factors and causal mechanisms associated with variations in outcome. This study will inform UK drug treatment policy and practice. Trial registration ISRCTN 01591254.

High-level production and purification in a functional state of an extrasynaptic gamma-aminobutyric acid type A receptor containing α4β3δ subunits

The inhibitory γ-aminobutyric acid type A receptors are implicated in numerous physiological processes, including cognition and inhibition of neurotransmission, rendering them important molecular targets for many classes of drugs. Functionally, the entire GABAAR family of receptors can be subdivided into phasic, fast acting synaptic receptors, composed of α-, β- and γ-subunits, and tonic extrasynaptic receptors, many of which contain the δ-subunit in addition to α- and β-subunits. Whereas the subunit arrangement of the former group is agreed upon, that of the αβδ GABAARs remains unresolved by electrophysiological and pharmacological research. To resolve such issues will require biophysical techniques that demand quantities of receptor that have been previously unavailable. Therefore, we have engineered a stable cell line with tetracycline inducible expression of human α4-, β3- and N-terminally Flag-tagged δ-subunits. This cell line achieved a specific activity between 15 and 20 pmol [3H]muscimol sites/mg of membrane protein, making it possible to obtain 1 nmole of purified α4β3δ GABAAR from sixty 15-cm culture dishes. When induced, these cells exhibited agonist-induced currents with characteristics comparable to those previously reported for this receptor and a pharmacology that included strong modulation by etomidate and the δ-subunit-specific ligand, DS2. Immunoaffinity purification and reconstitution in CHAPS/asolectin micelles resulted in the retention of equilibrium allosteric interactions between the separate agonist, anesthetic and DS2 sites. Moreover, all three subunits retained glycosylation. The establishment of this well-characterized cell line will allow molecular level studies of tonic receptors to be undertaken.

The association between biopsychosocial factors and disability in a national health survey in South Africa

The association between psychosocial factors and disability is less clear. This study investigated the biological and psychosocial (employment and psychological distress) factors associated with level of disability in an adult sample in South Africa. Data were analysed from a cross-sectional survey among adults aged 18-64 (n = 4974). Multiple linear regression was used to investigate the associations of the selected variables with disability. The mean percentage score on the WHODAS scale of disability was 5.31% (95% CI: 4.74-5.88). Age (p < 0.001) and race (p = 0.0002) were significantly associated with disability, and history of stroke (β = 7.19, 95% CI: 3.19-11.20) and heart-related conditions (β = 2.08, 95% CI: [0.23-3.93) showed positive associations. Of the psychosocial variables, psychological distress (β = 10.49 [8.63-12.35]) showed a strong positive association while employment (-1.62 [-2.36 to -0.88]) showed a negative association with disability. The association between demographic factors, medical conditions and increased disability confirms the findings in the literature. The finding that psychological distress is associated with increased disability has not been frequently reported. This study highlights specific psychosocial targets that may be usefully addressed by health policies and interventions in order to improve disability management.

Synthesis and pharmacological evaluation of neurosteroid photoaffinity ligands

Neuroactive steroids are potent positive allosteric modulators of GABA_A receptors (GABA_AR), but the locations of their GABA_AR binding sites remain poorly defined. To discover these sites, we synthesized two photoreactive analogs of alphaxalone, an anesthetic neurosteroid targeting GABA_AR, 11β-(4-azido-2,3,5,6-tetrafluorobenzoyloxy)allopregnanolone, (F4N3Bzoxy-AP) and 11-aziallopregnanolone (11-AziAP). Both photoprobes acted with equal or higher potency than alphaxalone as general anesthetics and potentiators of GABA_AR responses, left-shifting the GABA concentration - response curve for human α1β3γ2 GABA_ARs expressed in Xenopus oocytes, and enhancing [³H]muscimol binding to α1β3γ2 GABA_ARs expressed in HEK293 cells. With EC₅₀ of 110 nM, 11-AziAP is one the most potent general anesthetics reported. [³H]F4N3Bzoxy-AP and [³H]11-AziAP, at anesthetic concentrations, photoincorporated into α- and β-subunits of purified α1β3γ2 GABA_ARs, but labeling at the subunit level was not inhibited by alphaxalone (30 μM). The enhancement of photolabeling by ³H-azietomidate and ³H-mTFD-MPAB in the presence of either of the two steroid photoprobes indicates the neurosteroid binding site is different from, but allosterically related to, the etomidate and barbiturate sites. Our observations are consistent with two hypotheses. First, F4N3Bzoxy-AP and 11-aziAP bind to a high affinity site in such a pose that the 11-photoactivatable moiety, that is rigidly attached to the steroid backbone, points away from the protein. Second, F4N3Bzoxy-AP, 11-aziAP and other steroid anesthetics, which are present at very high concentration at the lipid-protein interface due to their high lipophilicity, act via low affinity sites, as proposed by Akk et al. (Psychoneuroendocrinology2009, 34S1, S59-S66).

Contrasting actions of a convulsant barbiturate and its anticonvulsant enantiomer on the α1 β3 γ2L GABAA receptor account for their in vivo effects

KEY POINTS

Most barbiturates are anaesthetics but unexpectedly a few are convulsants whose mechanism of action is poorly understood. We synthesized and characterized a novel pair of chiral barbiturates that are capable of photolabelling their binding sites on GABAA receptors. In mice the S-enantiomer is a convulsant, but the R-enantiomer is an anticonvulsant. The convulsant S-enantiomer binds solely at an inhibitory site. It is both an open state inhibitor and a resting state inhibitor. Its action is pH independent, suggesting the pyrimidine ring plays little part in binding. The inhibitory site is not enantioselective because the R-enantiomer inhibits with equal affinity. In contrast, only the anticonvulsant R-enantiomer binds to the enhancing site on open channels, causing them to stay open longer. The enhancing site is enantioselective. The in vivo actions of the convulsant S-enantiomer are accounted for by its interactions with GABAA receptors.

ABSTRACT

Most barbiturates are anaesthetics but a few unexpectedly are convulsants. We recently located the anaesthetic sites on GABAA receptors (GABAA Rs) by photolabelling with an anaesthetic barbiturate. To apply the same strategy to locate the convulsant sites requires the creation and mechanistic characterization of a suitable agent. We synthesized enantiomers of a novel, photoactivable barbiturate, 1-methyl-5-propyly-5-(m-trifluoromethyldiazirinyl) phenyl barbituric acid (mTFD-MPPB). In mice, S-mTFD-MPPB acted as a convulsant, whereas R-mTFD-MPPB acted as an anticonvulsant. Using patch clamp electrophysiology and fast solution exchange on recombinant human α1 β3 γ2L GABAA Rs expressed in HEK cells, we found that S-mTFD-MPPB inhibited GABA-induced currents, whereas R-mTFD-MPPB enhanced them. S-mTFD-MPPB caused inhibition by binding to either of two inhibitory sites on open channels with bimolecular kinetics. It also inhibited closed, resting state receptors at similar concentrations, decreasing the channel opening rate and shifting the GABA concentration-response curve to the right. R-mTFD-MPPB, like most anaesthetics, enhanced receptor gating by rapidly binding to allosteric sites on open channels, initiating a rate-limiting conformation change to stabilized open channel states. These states had slower closing rates, thus shifting the GABA concentration-response curve to the left. Under conditions when most GABAA Rs were open, an inhibitory action of R-mTFD-MPPB was revealed that had a similar IC50 to that of S-mTFD-MPPB. Thus, the inhibitory sites are not enantioselective, and the convulsant action of S-mTFD-MPPB results from its negligible affinity for the enhancing, anaesthetic sites. Interactions with these two classes of barbiturate binding sites on GABAA Rs underlie the enantiomers' different pharmacological activities in mice.

ID: 74: A RETROSPECTIVE STUDY OF CORONARY ARTERY DISEASE IN PATIENTS WITH BODY MASS INDEX ≥30

Introduction

Coronary Artery Disease (CAD) is a major cause of morbidity and mortality worldwide, and although mortality is decreasing, prevalence of CAD is increasing. A number of modifiable risk factors (smoking) and non-modifiable risk factors (gender, age) have well established association with CAD, whereas other potential risk factors (such as obesity) are less well established. In this study, we evaluated the obesity as a single risk factor for CAD and evaluated the synergistic effect of obesity with the other risk factors.

Method

A retrospective study of 7,567 patients admitted to hospital for chest pain from 2005–2014 and underwent cardiac catheterization. Patients were divided into two groups: obese and normal with body mass index (BMI) calculated as ≥30 kg/m2 and ≤25, respectively. Patients with BMIs between 26 and 29 were excluded. We assessed the modifiable and non-modifiable risk factors in obese patients and the degree of CAD with coronary angiography as obstructive CAD (left main stenosis of ≥50% or any stenosis of ≥70%), non-obstructive CAD (≥1 stenosis ≥20% but no stenosis ≥70%) and normal coronaries.

Results

Of the 7,567 patients who underwent cardiac catheterization, 414 (5.5%) had a BMI ≥30. Of 414 obese patients, 332 (80%) had evidence of CAD. Obese patients displayed evidence of CAD at the age of 57 versus 63.3 in non-obese patients (p<0.001).

Of the 332 patients with CAD and obesity, 55.4% had obstructive CAD versus 44.6% with non-obstructive CAD. In obese patients with CAD, Male gender and history of smoking were major risk factors for development of obstructive CAD (p=0.001 and 0.01, respectively) while dyslipidemia was a major risk factor for non-obstructive CAD (p 0.01). Additionally, obese patients with more than one risk factor; developed obstructive CAD compared to non-obstructive CAD (p=0.003). Approximately 40% presented with STEMI, 30% with NSTEMI and 30% had stable angina as a primary diagnosis.

Of the 332 obese patients with CAD, 24% received medical treatment, 58% underwent percutaneous coronary intervention (PCI) and 18% obtained coronary artery bypass grafting (CABG).

In a gender comparison, average age of CAD in obese males were 55 years of age compared to 59 in females (p <0.001). Approximately 67% of males underwent PCI (OR: 2.4, 95% CI: 1.5–3.6, p<0.001) and 24% obtained CABG (OR: 3, 95% CI: 1.6–5.6, p<0.001), whereas in obese females 43% received medical therapy (OR: 9, 95% CI: 5–17, p<0.001).

Conclusion

Having a BMI ≥30 appears to correlate as a risk factor for early development of CAD. Severity of CAD in obese patients is depicted on non-modifiable and modifiable risk factors such as the male gender and smoking or greater than one risk factor, respectively. Early lifestyle modification and education may provide benefit in striving to aid decreasing incidents of CAD and possibly lowering cardiovascular events.

Kv3.3 Channels Bind Hax-1 and Arp2/3 to Assemble a Stable Local Actin Network that Regulates Channel Gating

Mutations in the Kv3.3 potassium channel (KCNC3) cause cerebellar neurodegeneration and impair auditory processing. The cytoplasmic C terminus of Kv3.3 contains a proline-rich domain conserved in proteins that activate actin nucleation through Arp2/3. We found that Kv3.3 recruits Arp2/3 to the plasma membrane, resulting in formation of a relatively stable cortical actin filament network resistant to cytochalasin D that inhibits fast barbed end actin assembly. These Kv3.3-associated actin structures are required to prevent very rapid N-type channel inactivation during short depolarizations of the plasma membrane. The effects of Kv3.3 on the actin cytoskeleton are mediated by the binding of the cytoplasmic C terminus of Kv3.3 to Hax-1, an anti-apoptotic protein that regulates actin nucleation through Arp2/3. A human Kv3.3 mutation within a conserved proline-rich domain produces channels that bind Hax-1 but are impaired in recruiting Arp2/3 to the plasma membrane, resulting in growth cones with deficient actin veils in stem cell-derived neurons.

Biological and psychosocial risk factors for psychotic major depression

AIMS

Few studies have investigated risk factors for psychotic major depression (PMD). We aimed to investigate the biological and psychosocial risk factors associated with PMD compared with other psychotic disorders.

METHODS

Based on the aetiology and ethnicity in schizophrenia and other psychoses (ÆSOP) study, we used a case-control study to identify and recruit, at baseline and 10-year follow-up, all first episode cases of psychosis, presenting for the first time to specialist mental health services in defined catchment areas in the UK. Population-based controls were recruited from the same areas. Data were collected on: sociodemographics; social isolation; childhood adversity; life events; minor physical anomalies; and neurological soft signs.

RESULTS

Living alone (aOR = 2.26, CI = 1.21-4.23), basic level qualification (aOR = 2.89, CI = 1.08-7.74), being unemployed (aOR = 2.12, CI = 1.13-3.96), having contact with friends less than monthly (aOR = 4.24, CI = 1.62-11.14), having no close confidants (aOR = 4.71, CI = 2.08-10.68), having experienced childhood adversity (aOR = 2.57, CI = 1.02-6.44), family history of mental illness (aOR = 10.68, CI = 5.06-22.52), family history of psychosis (aOR = 12.85, CI = 5.24-31.51), and having more neurological soft signs (aOR = 1.15, CI = 1.07-1.24) were all associated with a follow-up diagnosis of PMD and schizophrenia. Few variables associated with PMD were also associated with a diagnosis of bipolar disorder. Minor physical anomalies were associated with a follow-up diagnosis of schizophrenia and bipolar disorder, but not PMD.

CONCLUSIONS

Risk factors associated with PMD appear to overlap with those for schizophrenia, but less so for bipolar disorder. Future work on the differential aetiology of PMD, from other psychoses is needed to find the 'specifier' between PMD and other psychoses. Future research on aetiology in PMD, and perhaps other psychoses, should account for diagnostic change.

Positive and Negative Allosteric Modulation of an α1β3γ2 γ-Aminobutyric Acid Type A (GABAA) Receptor by Binding to a Site in the Transmembrane Domain at the γ+-β- Interface

In the process of developing safer general anesthetics, isomers of anesthetic ethers and barbiturates have been discovered that act as convulsants and inhibitors of γ-aminobutyric acid type A receptors (GABAARs) rather than potentiators. It is unknown whether these convulsants act as negative allosteric modulators by binding to the intersubunit anesthetic-binding sites in the GABAAR transmembrane domain (Chiara, D. C., Jayakar, S. S., Zhou, X., Zhang, X., Savechenkov, P. Y., Bruzik, K. S., Miller, K. W., and Cohen, J. B. (2013) J. Biol. Chem. 288, 19343-19357) or to known convulsant sites in the ion channel or extracellular domains. Here, we show that S-1-methyl-5-propyl-5-(m-trifluoromethyl-diazirynylphenyl) barbituric acid (S-mTFD-MPPB), a photoreactive analog of the convulsant barbiturate S-MPPB, inhibits α1β3γ2 but potentiates α1β3 GABAAR responses. In the α1β3γ2 GABAAR, S-mTFD-MPPB binds in the transmembrane domain with high affinity to the γ(+)-β(-) subunit interface site with negative energetic coupling to GABA binding in the extracellular domain at the β(+)-α(-) subunit interfaces. GABA inhibits S-[(3)H]mTFD-MPPB photolabeling of γ2Ser-280 (γM2-15') in this site. In contrast, within the same site GABA enhances photolabeling of β3Met-227 in βM1 by an anesthetic barbiturate, R-[(3)H]methyl-5-allyl-5-(m-trifluoromethyl-diazirynylphenyl)barbituric acid (mTFD-MPAB), which differs from S-mTFD-MPPB in structure only by chirality and two hydrogens (propyl versus allyl). S-mTFD-MPPB and R-mTFD-MPAB are predicted to bind in different orientations at the γ(+)-β(-) site, based upon the distance in GABAAR homology models between γ2Ser-280 and β3Met-227. These results provide an explanation for S-mTFD-MPPB inhibition of α1β3γ2 GABAAR function and provide a first demonstration that an intersubunit-binding site in the GABAAR transmembrane domain binds negative and positive allosteric modulators.

Diagnostic Disparity in Solitary Cysticercosis of the Forearm in a Child

Solitary cysticercosis of muscle is a rare disease causing diagnostic dilemma. Cysticercosis commonly affects the central nervous system and other tissues by dissemination imposing a serious health problem. We report this rare presentation of solitary cysticercosis of flexor digitorum superficialis in a five year old otherwise healthy child. The fine needle aspiration cytology and histopathological diagnosis were inconclusive but ultrasonography of the muscle clinched the diagnosis.

Haplosufficient genomic androgen receptor signaling is adequate to protect female mice from induction of polycystic ovary syndrome features by prenatal hyperandrogenization

Polycystic ovary syndrome (PCOS) is associated with reproductive, endocrine, and metabolic abnormalities. Because hyperandrogenism is the most consistent PCOS feature, we used wild-type (WT) and androgen receptor (AR) knockout (ARKO) mice, together with a mouse model of PCOS, to investigate the contribution of genomic AR-mediated actions in the development of PCOS traits. PCOS features were induced by prenatal exposure to dihydrotestosterone (250 μg) or oil vehicle (control) on days 16-18 of gestation in WT, heterozygote, and homozygote ARKO mice. DHT treatment of WT mice induced ovarian cysts (100% vs 0%), disrupted estrous cycles (42% vs 100% cycling), and led to fewer corpora lutea (5.0±0.4 vs 9.8±1.8). However, diestrus serum LH and FSH, and estradiol-induced-negative feedback as well as hypothalamic expression of kisspeptin, neurokinin B, and dynorphin, were unaffected by DHT treatment in WT mice. DHT-treated WT mice exhibited a more than 48% increase in adipocyte area but without changes in body fat. In contrast, heterozygous and homozygous ARKO mice exposed to DHT maintained comparable ovarian (histo)morphology, estrous cycling, and corpora lutea numbers, without any increase in adipocyte size. These findings provide strong evidence that genomic AR signaling is an important mediator in the development of these PCOS traits with a dose dependency that allows even AR haplosufficiency to prevent induction by prenatal androgenization of PCOS features in adult life.

Predictors of complications in gynaecological oncological surgery: a prospective multicentre study (UKGOSOC-UK gynaecological oncology surgical outcomes and complications)

BACKGROUND

There are limited data on surgical outcomes in gynaecological oncology. We report on predictors of complications in a multicentre prospective study.

METHODS

Data on surgical procedures and resulting complications were contemporaneously recorded on consented patients in 10 participating UK gynaecological cancer centres. Patients were sent follow-up letters to capture any further complications. Post-operative (Post-op) complications were graded (I-V) in increasing severity using the Clavien-Dindo system. Grade I complications were excluded from the analysis. Univariable and multivariable regression was used to identify predictors of complications using all surgery for intra-operative (Intra-op) and only those with both hospital and patient-reported data for Post-op complications.

RESULTS

Prospective data were available on 2948 major operations undertaken between April 2010 and February 2012. Median age was 62 years, with 35% obese and 20.4% ASA grade ⩾3. Consultant gynaecological oncologists performed 74.3% of operations. Intra-op complications were reported in 139 of 2948 and Grade II-V Post-op complications in 379 of 1462 surgeries. The predictors of risk were different for Intra-op and Post-op complications. For Intra-op complications, previous abdominal surgery, metabolic/endocrine disorders (excluding diabetes), surgical complexity and final diagnosis were significant in univariable and multivariable regression (P<0.05), with diabetes only in multivariable regression (P=0.006). For Post-op complications, age, comorbidity status, diabetes, surgical approach, duration of surgery, and final diagnosis were significant in both univariable and multivariable regression (P<0.05).

CONCLUSIONS

This multicentre prospective audit benchmarks the considerable morbidity associated with gynaecological oncology surgery. There are significant patient and surgical factors that influence this risk.