Recurrent Pericardial Effusions and Intrapericardial Thrombi of Unknown Etiology

This is a case of a 76-year-old male with an initial presentation consistent with idiopathic pericarditis. He presented repeatedly with recurrent pericardial effusions and intrapericardial thrombi of unknown etiology. Surgical evacuation of the thrombi was performed twice, and the second surgery demonstrated a cardiac tumour. Cardiac MRI and pathology were consistent with angiosarcoma. In cases of recurrent pericardial effusions and thrombi, we recommend a high index of suspicion for cardiac tumours. Further, we recommend early consideration of cardiac MRI or PET and early referral to imaging specialists and cardiac surgeons with experience in cardiac tumours.

An Unlikely Source of Iodine Uptake: A Bronchogenic Cyst Masquerading as Metastatic Thyroid Cancer

Radioactive iodine therapy and posttreatment scanning are essential components of differentiated thyroid carcinoma treatment and detection of metastatic disease. False-positive results can be seen on an I-131 scan and are important for clinicians to be aware of. Here, we present a case of a 33-year-old female with follicular thyroid carcinoma who was noted to have an area of moderate uptake in the chest on a whole-body scan following remnant ablation with 30 mCi of I-131 (1.11GBq) concerning for a metastatic hilar lymph node. This was determined to be a mediastinal bronchogenic cyst on surgical pathology. It has been previously proposed that the expression of sodium iodide symporters in some bronchogenic cysts could be the mechanism by which iodine uptake is seen within them. We were able to demonstrate positive immunohistochemical staining for both sodium iodide symporter and the associated paired box gene 8 transcription factor in the cyst sample, which supports the proposed theory.

Machine learning identifies a COVID-19-specific phenotype in university students using a mental health app

Background

Advances in smartphone technology have allowed people to access mental healthcare via digital apps from wherever and whenever they choose. University students experience a high burden of mental health concerns. Although these apps improve mental health symptoms, user engagement has remained low. Studies have shown that users can be subgrouped based on unique characteristics that just-in-time adaptive interventions (JITAIs) can use to improve engagement. To date, however, no studies have examined the effect of the COVID-19 pandemic on these subgroups.

Objective

Here, we sought to examine user subgroup characteristics across three COVID-19-specific timepoints: during lockdown, immediately following lockdown, and three months after lockdown ended.

Methods

To do this, we used a two-step machine learning approach combining unsupervised and supervised machine learning.

Results

We demonstrate that there are three unique subgroups of university students who access mental health apps. Two of these, with either higher or lower mental well-being, were defined by characteristics that were stable across COVID-19 timepoints. The third, situational well-being, had characteristics that were timepoint-dependent, suggesting that they are highly influenced by traumatic stressors and stressful situations. This subgroup also showed feelings and behaviours consistent with burnout.

Conclusions

Overall, our findings clearly suggest that user subgroups are unique: they have different characteristics and therefore likely have different mental healthcare goals. Our findings also highlight the importance of including questions and additional interventions targeting traumatic stress(ors), reason(s) for use, and burnout in JITAI-style mental health apps to improve engagement.

Developing and delivering a hybrid Cardiac Rehabilitation Phase II exercise program during the COVID-19 pandemic: a quality improvement program

The COVID-19 pandemic resulted in the cessation of approximately 75% of cardiac rehabilitation (CR) programmes worldwide. In March 2020, CR phase II (CRP2) services were stopped in Qatar. Multiple studies had shown safety, effectiveness, reduced cost of delivery and improved participation with hybrid CR. A multidisciplinary team reviewed various alternative models for delivery and decided to implement a hybrid CRP2 exercise programme (HCRP2-EP) to ensure continuation of our patient care. Our aim was to enrol in the HCRP2-EP 70% of all eligible patients by 30 September 2020. Institute for Health Care Improvement's collaborative model was adopted. Multiple plan-do-study-act cycles were used to test change ideas. The outcomes of the project were analysed using standard run chart rules to detect the changes in outcomes over time. This project was implemented from March 2020, and the male patients enrolled between August 2020 and April 2021, with sustained monthly median enrolment above target of 70% throughout. As for our secondary outcome, 75.8% of the male patients who completed HCRP2-EP showed a meaningful change in peak exercise capacity of ≥10% (mean change 17%±6%). There were no major adverse events reported, and the median Patient Satisfaction Score was 96% well above the institutional target of 90%. This shows a well-designed quality improvement programme is an appropriate strategy for implementing HCRP2-EP in a clinical setting, and HCRP2-EP is a feasible, effective and safe intervention in eligible male patients with cardiovascular disease.

Techniques improving electrical cardioversion success for patients with atrial fibrillation: a systematic review and meta-analysis

AIMS

Electrical cardioversion is commonly used to restore sinus rhythm in patients with atrial fibrillation (AF), but procedural technique and clinical success vary. We sought to identify techniques associated with electrical cardioversion success for AF patients.

METHODS AND RESULTS

We searched MEDLINE, EMBASE, CENTRAL, and the grey literature from inception to October 2022. We abstracted data on initial and cumulative cardioversion success. We pooled data using random-effects models. From 15 207 citations, we identified 45 randomized trials and 16 observational studies. In randomized trials, biphasic when compared with monophasic waveforms resulted in higher rates of initial [16 trials, risk ratio (RR) 1.71, 95% CI 1.29-2.28] and cumulative success (18 trials, RR 1.10, 95% CI 1.04-1.16). Fixed, high-energy (≥200 J) shocks when compared with escalating energy resulted in a higher rate of initial success (four trials, RR 1.62, 95% CI 1.33-1.98). Manual pressure when compared with no pressure resulted in higher rates of initial (two trials, RR 2.19, 95% CI 1.21-3.95) and cumulative success (two trials, RR 1.19, 95% CI 1.06-1.34). Cardioversion success did not differ significantly for other interventions, including: antero-apical/lateral vs. antero-posterior positioned pads (initial: 11 trials, RR 1.16, 95% CI 0.97-1.39; cumulative: 14 trials, RR 1.01, 95% CI 0.96-1.06); rectilinear/pulsed biphasic vs. biphasic truncated exponential waveform (initial: four trials, RR 1.11, 95% CI 0.91-1.34; cumulative: four trials, RR 0.98, 95% CI 0.89-1.08) and cathodal vs. anodal configuration (cumulative: two trials, RR 0.99, 95% CI 0.92-1.07).

CONCLUSIONS

Biphasic waveforms, high-energy shocks, and manual pressure increase the success of electrical cardioversion for AF. Other interventions, especially pad positioning, require further study.

Not all roads lead to the immune system: the genetic basis of multiple sclerosis severity

Multiple sclerosis is a leading cause of neurological disability in adults. Heterogeneity in multiple sclerosis clinical presentation has posed a major challenge for identifying genetic variants associated with disease outcomes.

To overcome this challenge, we used prospectively ascertained clinical outcomes data from the largest international multiple sclerosis Registry, MSBase. We assembled a cohort of deeply phenotyped individuals of European ancestry with relapse-onset multiple sclerosis. We used unbiased genome-wide association study and machine learning approaches to assess the genetic contribution to longitudinally defined multiple sclerosis severity phenotypes in 1,813 individuals.

Our primary analyses did not identify any genetic variants of moderate to large effect sizes that met genome-wide significance thresholds. The strongest signal was associated with rs7289446 (β=-0.4882, P = 2.73 × 10−7), intronic to SEZ6L on chromosome 22. However, we demonstrate that clinical outcomes in relapse-onset multiple sclerosis are associated with multiple genetic loci of small effect sizes. Using a machine learning approach incorporating over 62,000 variants together with clinical and demographic variables available at multiple sclerosis disease onset, we could predict severity with an area under the receiver operator curve of 0.84 (95% CI 0.79–0.88). Our machine learning algorithm achieved positive predictive value for outcome assignation of 80% and negative predictive value of 88%. This outperformed our machine learning algorithm that contained clinical and demographic variables alone (area under the receiver operator curve 0.54, 95% CI 0.48–0.60).

Secondary, sex-stratified analyses identified two genetic loci that met genome-wide significance thresholds. One in females (rs10967273; βfemale =0.8289, P = 3.52 × 10−08), the other in males (rs698805; βmale = -1.5395, P = 4.35 × 10−08), providing some evidence for sex dimorphism in multiple sclerosis severity. Tissue enrichment and pathway analyses identified an overrepresentation of genes expressed in central nervous system compartments generally, and specifically in the cerebellum (P = 0.023). These involved mitochondrial function, synaptic plasticity, oligodendroglial biology, cellular senescence, calcium and g-protein receptor signalling pathways. We further identified six variants with strong evidence for regulating clinical outcomes, the strongest signal again intronic to SEZ6L (adjusted hazard ratio 0.72, P = 4.85 × 10−4).

Here we report a milestone in our progress towards understanding the clinical heterogeneity of multiple sclerosis outcomes, implicating functionally distinct mechanisms to multiple sclerosis risk. Importantly, we demonstrate that machine learning using common single nucleotide variant clusters, together with clinical variables readily available at diagnosis can improve prognostic capabilities at diagnosis, and with further validation has the potential to translate to meaningful clinical practice change.

Artificial Intelligence to Aid Glaucoma Diagnosis and Monitoring: State of the Art and New Directions

Recent developments in the use of artificial intelligence in the diagnosis and monitoring of glaucoma are discussed. To set the context and fix terminology, a brief historic overview of artificial intelligence is provided, along with some fundamentals of statistical modeling. Next, recent applications of artificial intelligence techniques in glaucoma diagnosis and the monitoring of glaucoma progression are reviewed, including the classification of visual field images and the detection of glaucomatous change in retinal nerve fiber layer thickness. Current challenges in the direct application of artificial intelligence to further our understating of this disease are also outlined. The article also discusses how the combined use of mathematical modeling and artificial intelligence may help to address these challenges, along with stronger communication between data scientists and clinicians.

Effects of adding hypertonic saline solutions and/or etilefrine to standard diuretics therapy in cirrhotic patients with ascites

OBJECTIVE

The renin-angiotensin-aldosterone system (RAAS) activation is the milestone in ascites formation. Hypertonic saline solution (HSS) has attracted considerable interest over the last years in ascites control. Other therapeutic models and concepts have been introduced to overcome diuretic resistance and control ascites. We aimed to evaluate the effects of adding HSS infusion and/or etilefrine to oral diuretics therapy on inflammatory and metabolic pathways, renal and systemic hemodynamics, and clinical outcomes by estimating the changes in selected biochemical and biological markers in cirrhotic patients with ascites.

PATIENTS AND METHODS

Ninety cirrhotic patients with ascites were studied after administration of HSS infusion (n=25) or etilefrine tablets (n=25), or both (n=25) plus standard diuretics therapy (SDT), or SDT alone (n=15). Serum levels of interleukin-6 (IL-6), aldosterone, leptin, and C-reactive protein (CRP). Hepatic and renal functions were measured at baseline, after eight days, then after 38 days.

RESULTS

A significant reduction in serum IL-6, serum aldosterone, Child-Pugh score, MELD-Na score, and increase in serum leptin, and mean arterial pressure (p<0.05) were noted after 38 days in HSS and combination groups. A significant improvement in diuresis, in all groups, urinary sodium excretion, and creatinine clearance (p<0.05) were increased after 38 days in all groups except the SDT group.

CONCLUSIONS

The results suggest that HSS, etilefrine, and their combination plus SDT are superior to SDT alone for ascites control and can exert some benefits on clinical, systemic, inflammatory, renal, and metabolic pathways without renal or hepatic dysfunction.

Drive line infection rate reduction by developing a fixation kit

Funding Acknowledgements

Type of funding sources: None.

Introduction

Continuous-flow left ventricular assist device (LVAD) therapy has become a standard therapy for patients suffering from end-stage heart failure. One of the serious adverse events during LVAD support is infection. Infections can trigger thromboembolic events, haemorrhagic cerebrovascular accidents , and are the second most common cause of death. Moreover, LVAD-related infection is the leading cause of re-admission and increases the cost of LVAD therapy considerably. Patients with an infection during LVAD support need a significantly prolonged hospital stay.

Background

Left ventricular assist device implantation is one of the operations that patients need special and distinctive health care, and therefore a specialized medical team has been appointed to examine these patients, but from the time the device is installed, these patients suffer from frequent infections at the drive line exit site, and therefore the responsible team faces a great challenge in combating this infection and reducing the infection rate and complications. One of the biggest problems is that we cannot find the exact type of dressing that is used to care for the exit, With the increase in the number of patients who have an infection in the drive line exit site, the team started to identify the reasons that lead to this, and it was found that failure to the fixation of the drive line is one of the biggest causes of infection, and patients reported that the movement of the drive line causes them severe pain and inflammation, which leads to many difficulties in their mobility and daily activities.

Aim

Reaching the best practice and reducing drive line infection rate by managing drive line fixation while increasing the number of the implanted devices.

Process: The LVAD nursing team started in collecting data related to the drive line infection and some modifications were implemented according to the available resources to be used in the drive line modified fixation technique:

Step 1: Our available adhesive dressings were used, and two small holes were made in the middle of it. Figure 1

Step 2: A small gauze strip was passed through the two holes to be fixed around the drive line. Figure 2

Step 3: Then a surgical blade used to make a whistling hole in the adhesive dressing to exit the drive line from it. Figure 3

Results

Based on:

Auditing charts and data collection it shows significant decrease in infection rates and re-admission related to drive line infection.

Recommendation

Develop new material for education

Videos in Arabic, Follow-up handbook and Posters.

Updating AHC staff with the latest driveline wound care protocol

Training sessions, Case study and Simulation lab.

Pre-treatment with antiarrhythmic drugs for elective electrical cardioversion of atrial fibrillation: a systematic review and network meta-analysis

AIMS

Our objective was to compare the efficacy of pre-treatment with different classes of anti-arrhythmic drugs (AADs) in patients with atrial fibrillation (AF) undergoing electrical cardioversion.

METHODS AND RESULTS

We performed a systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) comparing different AADs in patients with AF undergoing electrical cardioversion. We grouped AADs into five network nodes: no treatment or rate control, Class Ia, Class Ic, Class III, and amiodarone. Outcomes were (i) acute restoration and (ii) maintenance of sinus rhythm. We searched MEDLINE and EMBASE from inception until June 2020. We used Python 3.8.3 and R 3.6.2 for data analysis. We evaluated the overall certainty of evidence with the GRADE framework. We included 28 RCTs. Compared with no treatment or rate control, Class III AADs [odds ratio (OR): 2.41; 95% credible interval (CrI): 1.37 to 4.62, high certainty] and amiodarone (OR: 2.58; 95% CrI: 1.54 to 4.37, high certainty) improved restoration of sinus rhythm. Amiodarone improved long-term maintenance of sinus rhythm when compared with no treatment or rate control (OR: 5.37; 95% CrI: 4.00-7.39, high certainty), Class Ic (OR: 1.89; 95% CrI: 1.05-3.45, moderate certainty) and Class III AADs (OR: 2.19; 95% CrI: 1.39-3.26, high certainty).

CONCLUSION

Before electrical cardioversion of AF, treatment with Class III AADs or amiodarone improves the acute restoration of sinus rhythm. Amiodarone is most likely to improve the maintenance of sinus rhythm after electrical cardioversion, but Class Ic and Class III AADs are also effective.

Investigation of CACNA1I Cav3.3 Dysfunction in Hemiplegic Migraine

Familial hemiplegic migraine (FHM) is a severe neurogenetic disorder for which three causal genes, CACNA1A, SCN1A, and ATP1A2, have been implicated. However, more than 80% of referred diagnostic cases of hemiplegic migraine (HM) are negative for exonic mutations in these known FHM genes, suggesting the involvement of other genes. Using whole-exome sequencing data from 187 mutation-negative HM cases, we identified rare variants in the CACNA1I gene encoding the T-type calcium channel Cav3.3. Burden testing of CACNA1I variants showed a statistically significant increase in allelic burden in the HM case group compared to gnomAD (OR = 2.30, P = 0.00005) and the UK Biobank (OR = 2.32, P = 0.0004) databases. Dysfunction in T-type calcium channels, including Cav3.3, has been implicated in a range of neurological conditions, suggesting a potential role in HM. Using patch-clamp electrophysiology, we compared the biophysical properties of five Cav3.3 variants (p.R111G, p.M128L, p.D302G, p.R307H, and p.Q1158H) to wild-type (WT) channels expressed in HEK293T cells. We observed numerous functional alterations across the channels with Cav3.3-Q1158H showing the greatest differences compared to WT channels, including reduced current density, right-shifted voltage dependence of activation and inactivation, and slower current kinetics. Interestingly, we also found significant differences in the conductance properties exhibited by the Cav3.3-R307H and -Q1158H variants compared to WT channels under conditions of acidosis and alkalosis. In light of these data, we suggest that rare variants in CACNA1I may contribute to HM etiology.

Discriminating head trauma outcomes using machine learning and genomics

A percentage of the population suffers prolonged and persistent post-concussion symptoms (PCS) following average head injuries or develops severe neurological dysfunction following minor head trauma. Genetic variants that may contribute to individual response to head trauma have been investigated in some studies, but to date none have explored the use of machine learning (ML) methods with genomic data to specifically explore outcomes of head trauma. Whole exome sequencing (WES) was completed for three groups of individuals (N = 60): (a) 16 individuals with severe neurological responses to minor head trauma, (b) 26 individuals with persistent PCS and (c) 18 individuals with normal recovery from concussion or mTBI. Gradient boosted tree algorithms were applied to the data using XGBoost. By using variants with CADD scores above 15 in the training set (randomly sampled 70%), we identified signatures that accurately distinguish to accurately distinguish the test groups with an average area under the curve (AUC) of 0.8 (SE = 0.019). Metrics including positive and negative prediction values, as well as kappa were all within acceptable range to support the prediction accuracy. This study illustrates how ML methods in combination with WES data have the potential to predict severe or prolonged responses to head trauma from healthy recovery. KEY MESSAGES: Linear association analysis has been inconclusive in concussion genetics. Non-linear methods as boosted trees can offer better insights in small samples. Strong discrimination trends can be achieved from exome data of cases and controls.

Leveraging Unsupervised Machine Learning to Discover Patterns in Linguistic Health Summaries for Eldercare

The Center for Eldercare and Rehabilitation Technology, at University of Missouri, has researched the use of smart, unobtrusive sensors for older adult residents' health monitoring and alerting in aging-in-place communities for many years. Sensors placed in the apartments of older adult residents generate a deluge of daily data that is automatically aggregated, analyzed, and summarized to aid in health awareness, clinical care, and research for healthy aging. When anomalies or concerning trends are detected within the data, the sensor information is converted into linguistic health messages using fuzzy computational techniques, so as to make it understandable to the clinicians. Sensor data are analyzed at the individual level, therefore, through this study we aim to discover various combinations of patterns of anomalies happening together and recurrently in the older adult's population using these text summaries. Leveraging various computational text data processing techniques, we are able to extract relevant analytical features from the health messages. These features are transformed into a transactional encoding, then processed with frequent pattern mining techniques for association rule discovery. At individual level analysis, resident ID 3027 was considered as an exemplar to describe the analysis. Seven combinations of anomalies/rules/associations were discovered in this resident, out of which rule group three showed an increased recurrence during the COVID lockdown of facility. At the population level, a total of 38 associations were discovered that highlight the health patterns, and we continue to explore the health conditions associated with them. Ultimately, our goal is to correlate the combinations of anomalies with certain health conditions, which can then be leveraged for predictive analytics and preventative care. This will improve the current clinical care systems for older adult residents in smart sensor, aging-in-place communities.

Safety of Laser and Thermal Therapy During Rigid Bronchoscopy Using Manual Hand Jet Ventilation

INTRODUCTION

Thermal ablative therapies (laser, radiofrequency ablation, electrocautery, argon plasma coagulation) are often used during rigid bronchoscopy for the treatment of central airway obstructions (CAO). An airway fire is a feared complication that can occur during endobronchial thermal ablation.

MATERIALS AND METHODS

This was a single-center, retrospective, observational study. A total of 175 patients were reviewed undergoing rigid bronchoscopy in the operating room and bronchoscopy suite requiring manual hand jet ventilation and thermal therapy between September 2014 and September 2018. The study objective was to determine the safety of manual hand jet ventilation during endobronchial thermal therapies with rigid bronchoscopy.

RESULTS

Over a five-year period, 175 patients underwent endobronchial thermal therapy during rigid bronchoscopy with manual hand jet ventilation for the treatment CAOs. Immediately prior to thermal therapy activation, jet ventilation was paused. No incidences (0/175) of airway fires occurred despite immediate delivery of thermal energy following a jet ventilation hold.

CONCLUSIONS

Results of our study show that performing thermal ablative therapy during rigid bronchoscopy with jet ventilation using a breath-hold technique is safe.

Recent Advances in the Treatment of Gliomas: The Multimodal Care Therapy

BACKGROUND: Glioblastoma (GBM) is the most devastating primary malignancy of the central nervous system in adults. At present, standard treatment consists of maximal safe surgical resection followed by radiotherapy (60 Gray) with concomitant daily temozolomide chemotherapy. Low-grade gliomas constitute approximately 15% of the nearly primary brain tumors diagnosed in adults each year. Extent of tumor resection has become a strong predictor of patient outcomes, alongside patient age, performance status, tumor histology, and molecular genetics (isocitrate dehydrogenase-1 and 1p/19q codeletion status). Over the past two decades, surgeons have emphasized the importance of maximizing extent of resection and its impact on overall survival, progression-free survival, and time to malignant transformation. AIM: We aimed to present recent advances in the treatment of gliomas. METHODS: This is a prospective analysis of 50 patients diagnosed with gliomas which are enrolled in a joint supervision between Kasr Al Aini Hospital, Cairo University, Egypt, and Coventry University Hospitals, England. RESULTS: The study included 50 patients, 31 males and 19 females, ages ranged from 21 to 75 years (mean age 47.5 years). Gross total resection was achieved in 28 patients (56%). The most common surgical complication in our series was post-operative transient weakness in 4 patients (8%). Mean true survival of low-grade glioma patients was 40.5 months while the mean true survival for anaplastic astrocytoma (Grade 3) patients was 38 months and that of GBM (Grade 4) patients was 18.8 months. CONCLUSION: Despite persistent limitations in the quality of data, mounting evidence suggests that more extensive surgical resection is associated with longer life expectancy for both low- and high-grade gliomas.

Repetitive Transcranial Magnetic Stimulation For The Treatment of Chronic Tinnitus: A Preliminary Study of The Influence of Traumatic Brain Injury on Treatment Response

This study aims to test whether the efficacy of repetitive Transcranial Magnetic Stimulation (rTMS) differs between patients who developed tinnitus following a traumatic brain injury (TBI), and those without a history of TBI. This was a parallel pilot, open-label, non-randomized, clinical trial to compare the efficacy of low frequency rTMS on tinnitus symptoms in patients with and without a TBI history. Patients with moderate to severe tinnitus symptoms based on the Tinnitus Handicap Inventory (THI) and the Tinnitus Functional Index (TFI) were enrolled in the study. Validated questionnaires (THI and TFI) were used to quantify the severity of tinnitus symptoms and hearing impairment (Hearing Handicap Index - HHI) before and after ten sessions of rTMS of the left primary auditory cortex. Hearing threshold levels as well as speech reception and speech discrimination thresholds were also compared. The number of patients who experienced a reduction in their subjective tinnitus symptoms was greater and sustained longer in patients without a history of TBI. The same was seen with subjective symptoms of hearing impairment. In conclusion, our preliminary results suggest tinnitus patients without a history of TBI respond better to low frequency rTMS than those with a history of TBI, suggesting that treatments could be more effective if tailored to tinnitus etiology.

Incidence and recurrence of new-onset atrial fibrillation detected during hospitalization for non-cardiac surgery: a systematic review and meta-analysis

PURPOSE

This systematic review aimed to summarize reports of the incidence and long-term recurrence of new-onset atrial fibrillation (AF) associated with non-cardiac surgery.

SOURCES

We searched CENTRAL, MEDLINE and EMBASE from inception to November 2019. We included studies that reported on the incidence of new-onset perioperative AF during hospitalization for non-cardiac surgery and/or AF recurrence in such patients following discharge. Reviewers screened articles and abstracted data independently and in duplicate. We assessed study quality by appraising methodology for collecting AF history, incident AF during hospitalization, and AF recurrence after discharge.

PRINCIPAL FINDINGS

From 39,233 citations screened, 346 studies that enrolled a total of 5,829,758 patients met eligibility criteria. Only 27 studies used prospective, continuous inpatient electrocardiographic (ECG) monitoring to detect incident AF. Overall, the incidence of postoperative AF during hospitalization ranged from 0.004 to 50.3%, with a median [interquartile range] of 8.7 [3.8-15.0]%. Atrial fibrillation incidence varied with type of surgery. Prospective studies using continuous ECG monitoring reported significantly higher incidences of AF than those that did not (13.9% vs 1.9%, respectively; P < 0.001). A total of 13 studies (25,726 patients) with follow-up up to 5.4 years reported on AF recurrence following hospital discharge; only one study used a prospective systematic monitoring protocol. Recurrence rates ranged from 0 to 37.3%.

CONCLUSIONS

Rates of AF incidence first detected following non-cardiac surgery and long-term AF recurrence vary markedly. Differences in the intensity of ECG monitoring and type of surgery may account for this variation.

TRIAL REGISTRATION

PROSPERO (CRD42017068055); registered 1 September 2017.

Comprehensive Exonic Sequencing of Hemiplegic Migraine-Related Genes in a Cohort of Suspected Probands Identifies Known and Potential Pathogenic Variants

Hemiplegic migraine (HM) is a rare migraine disorder with aura subtype including temporary weakness and visual, sensory, and/or speech symptoms. To date, three main genes—CACNA1A, ATP1A2, and SCN1A—have been found to cause HM. These encode ion channels or transporters, important for regulating neuronal ion balance and synaptic transmission, leading to HM being described as a channelopathy. However, <20% of HM cases referred for genetic testing have mutations in these genes and other genes with roles in ion and solute transport, and neurotransmission has also been implicated in some HM cases. In this study, we performed whole exome sequencing for 187 suspected HM probands referred for genetic testing, but found to be negative for CACNA1A, ATP1A2, and SCN1A mutations, and applied targeted analysis of whole exome sequencing data for rare missense or potential protein-altering variants in the PRRT2, PNKD, SLC1A3, SLC2A1, SLC4A4, ATP1A3, and ATP1A4 genes. We identified known mutations and some potentially pathogenic variants in each of these genes in specific cases, suggesting that their screening improves molecular diagnosis for the disorder. However, the majority of HM patients were found not to have candidate mutations in any of the previously reported HM genes, suggesting that additional genetic factors contributing to the disorder are yet to be identified.

Exploring Neuronal Vulnerability to Head Trauma Using a Whole Exome Approach

Brain injuries are associated with oxidative stress and a need to restore neuronal homeostasis. Mutations in ion channel genes, in particular CACNA1A, have been implicated in familial hemiplegic migraine (FHM) and in the development of concussion-related symptoms in response to trivial head trauma. The aim of this study was to explore the potential role of variants in other ion channel genes in the development of such responses. We conducted whole exome sequencing (WES) on16 individuals who developed a range of neurological and concussion-related symptoms following minor or trivial head injuries. All individuals were initially tested and shown to be negative for mutations in known FHM genes. Variants identified from the WES results were filtered to identify rare variants (minor allele frequency [MAF] <0.01) in genes related to neural processes as well as genes highly expressed in the brain using a combination of in silico prediction tools (SIFT, PolyPhen, PredictSNP, Mutation Taster, and Mutation Assessor). Rare (MAF <0.001) or novel heterozygous variants in 7 ion channel genes were identified in 37.5% (6/16) of the cases (CACNA1I, CACNA1C, ATP10A, ATP7B, KCNAB1, KCNJ10, and SLC26A4), rare variants in neurotransmitter genes were found in 2 cases (GABRG1 and GRIK1), and rare variants in 3 ubiquitin-related genes identified in 4 cases (SQSTM1, TRIM2, and HECTD1). In this study, the largest proportion of potentially pathogenic variants in individuals with severe responses to minor head trauma were identified in genes previously implicated in migraine and seizure-related autosomal recessive neurological disorders. Together with results implicating variants in the hemiplegic migraine genes, CACNA1A and ATP1A2, in severe head trauma response, our results support a role for heterozygous deleterious mutations in genes implicated in neurological dysfunction and potentially increasing the risk of poor response to trivial head trauma.

Regenerative Metaplastic Clones in COPD Lung Drive Inflammation and Fibrosis

Chronic obstructive pulmonary disease (COPD) is a progressive condition of chronic bronchitis, small airway obstruction, and emphysema that represents a leading cause of death worldwide. While inflammation, fibrosis, mucus hypersecretion, and metaplastic epithelial lesions are hallmarks of this disease, their origins and dependent relationships remain unclear. Here we apply single-cell cloning technologies to lung tissue of patients with and without COPD. Unlike control lungs, which were dominated by normal distal airway progenitor cells, COPD lungs were inundated by three variant progenitors epigenetically committed to distinct metaplastic lesions. When transplanted to immunodeficient mice, these variant clones induced pathology akin to the mucous and squamous metaplasia, neutrophilic inflammation, and fibrosis seen in COPD. Remarkably, similar variants pre-exist as minor constituents of control and fetal lung and conceivably act in normal processes of immune surveillance. However, these same variants likely catalyze the pathologic and progressive features of COPD when expanded to high numbers.

Targeted next generation sequencing identifies a genetic spectrum of DNA variants in patients with hemiplegic migraine

Objective:

Hemiplegic migraine in both familial (FHM) and sporadic (SHM) forms is a rare subtype of migraine with aura that can be traced to mutations in the CACNA1A, ATP1A2 and SCN1A genes. It is characterised by severe attacks of typical migraine accompanied by hemiparesis, as well as episodes of complex aura that vary significantly between individuals.

Methods:

Using a targeted next generation sequencing (NGS) multigene panel, we have sequenced the genomic DNA of 172 suspected hemiplegic migraine cases, in whom no mutation had previously been found by Sanger sequencing (SS) of a limited number of exons with high mutation frequency in FHM genes.

Results:

Genetic screening identified 29 variants, 10 of which were novel, in 35 cases in the three FHM genes ( CACNA1A, ATP1A2 and SCN1A). Interestingly, in this suspected HM cohort, the ATP1A2 gene harboured the highest number of variants with 24/35 cases (68.6%), while CACNA1A ranked the second gene, with 5 variants identified in 7/35 cases (20%). All detected variants were confirmed by SS and were absent in 100 non-migraine healthy control individuals. Assessment of variants with the American College of Medical Genetics and Genomics guidelines classified 8 variants as pathogenic, 3 as likely pathogenic and 18 as variants of unknown significance. Targeted NGS gene panel increased the diagnostic yield by fourfold over iterative SS in our diagnostics facility.

Conclusion:

We have identified 29 potentially causative variants in an Australian and New Zealand cohort of suspected HM cases and found that the ATP1A2 gene was the most commonly mutated gene. Our results suggest that screening using NGS multigene panels to investigate ATP1A2 alongside CACNA1A and SCN1A is a clinically useful and efficient method.

Electrosurgical and Laser Therapy Tools for the Treatment of Malignant Central Airway Obstructions

Central airway obstruction (CAO) is associated with significant morbidity and increased mortality. Bronchoscopic electrosurgical and laser ablative tools have proven to be safe and effective instruments for the treatment of malignant CAO. Although therapeutic modalities such as electrocautery, argon plasma coagulation, and laser have been used for decades, additional tools including radiofrequency ablation catheters continue to be developed for the treatment of CAO. These modalities are considered safe in the hands of experienced operators, although serious complications can occur. This review describes various electrosurgical and laser therapy tools used for the treatment of malignant CAO along with the specific advantages and disadvantages of each device.

Saliva as a comparable-quality source of DNA for Whole Exome Sequencing on Ion platforms

BACKGROUND

Whole Exome Sequencing (WES) utilises overlapping fragments prone to sequencing artefacts. Saliva, a non-invasive source of DNA, has been successfully used in WES studies on various platforms. This study explored the validity and quality of DNA sourced from saliva compared to whole blood on an Ion Platform.

METHODS

DNA was extracted from both sample types from four individuals. WES, performed on the Ion Proton platform was assessed for quality metrics (Depth, Genotyping Quality, etc.) and variant identification for the same source sample-pairs.

RESULTS

No significant differences in quality metrics were identified between data obtained from whole blood and saliva samples, with several saliva samples demonstrating higher coverage depth. Variants within the same sample, from the two genomic DNA sources, had an average concordance similar to other studies and platforms with different chemistry.

CONCLUSION

Saliva-extracted DNA provides comparable sequencing quality to whole blood for WES on Ion Torrent Platforms.

Bronchoscope-Guided Percutaneous Endoscopic Gastrostomy Tube Placement by Interventional Pulmonologists: A Feasibility and Safety Study

BACKGROUND

Percutaneous endoscopic gastrostomy (PEG) tube placement is a procedure frequently done in the intensive care unit. The use of a traditional endoscope can be difficult in cases of esophageal stenosis and theoretically confers an increased risk of infection due to its complex architecture. We describe a technique using the bronchoscope, which allows navigation through stenotic esophageal lesions and also minimizes the risk of endoscopy-associated infections.

METHODS

Prospective series of patients who had PEG tube placement guided by a bronchoscope. Procedural outcomes including successful placement, duration of the entire procedure, time needed for passage of the bronchoscope from the oropharynx to the major curvature, PEG tube removal rate, and mortality were collected. Procedural adverse events, including infections and long-term PEG-related complications, were recorded.

RESULTS

A total of 84 patients underwent bronchoscope-guided PEG tube placement. Percutaneous endoscopic gastrostomy tube insertion was completed successfully in 82 (97.6%) patients. Percutaneous endoscopic gastrostomy tube placement was performed immediately following percutaneous tracheostomy in 82.1%. Thirty-day mortality and 1-year mortality were 11.9% and 31%, respectively. Overall, minor complications occurred in 2.4% of patients, while there were no major complications. No serious infectious complications were identified and no endoscope-associated hospital acquired infections were documented.

CONCLUSIONS

The use of the bronchoscope can be safely and effectively used for PEG tube placement. The use of bronchoscope rather than a gastroscope has several advantages, which include the ease of navigating through complex aerodigestive disorders such as strictures and fistulas as well as decreased health-care utilization. In addition, it may have a theoretical advantage of minimizing infections related to complex endoscopes.

Patterns of Corneal Topography after Penetrating Keratoplasty

Background

The topography of corneas after penetrating keratoplasty is highly variable. We classify the topography into five groups.

Methods

We performed videokeratography on 45 clear compact penetrating keratoplasties, with all sutures removed. Three ophthalmologists classified the keratographs independently into five previously defined topographic groups, based on the pattern of the normalized color-coded videokeratograph.

Results

The five topographic patterns included: prolate bow tie, 14 (30%); oblate bow tie, 14 (30%); mixed prolate and oblate bow tie, 8 (17%); asymmetric, 3 (9%); and steep/flat, 6 (14%). The three ophthalmologists agreed in their initial classification in 87% of the cases and after discussion, in 96%.

Conclusion

The topography of the cornea after penetrating keratoplasty can be classified into five qualitative groups by trained observers, with good clinical reliability.

Raman spectroscopy for cytopathology of exfoliated cervical cells

Cervical cancer is the fourth most common cancer affecting women worldwide but mortality can be decreased by early detection of pre-malignant lesions. The Pap smear test is the most commonly used method in cervical cancer screening programmes. Although specificity is high for this test, it is widely acknowledged that sensitivity can be poor mainly due to the subjective nature of the test. There is a need for new objective tests for the early detection of pre-malignant cervical lesions. Over the past two decades, Raman spectroscopy has emerged as a promising new technology for cancer screening and diagnosis. The aim of this study was to evaluate the potential of Raman spectroscopy for cervical cancer screening using both Cervical Intraepithelial Neoplasia (CIN) and Squamous Intraepithelial Lesion (SIL) classification terminology. ThinPrep® Pap samples were recruited from a cervical screening population. Raman spectra were recorded from single cell nuclei and subjected to multivariate statistical analysis. Normal and abnormal ThinPrep® samples were discriminated based on the biochemical fingerprint of the cells using Principal Component Analysis (PCA). Principal Component Analysis - Linear Discriminant Analysis (PCA-LDA) was employed to build classification models based on either CIN or SIL terminology. This study has shown that Raman spectroscopy can be successfully applied to the study of routine cervical cytology samples from a cervical screening programme and that the use of CIN terminology resulted in improved sensitivity for high grade cases.

Abstract C26: Analysis of stem cell number & potency in African-American breast tissue

Breast cancer (BC) survival among African-American (AA) women 5 years after initial diagnosis is only 74%, significantly lower than the 88% survival observed in women of European white (EW) ancestry. The differences in outcomes have been attributed to the greater prevalence of Triple Negative Breast Cancer (TNBC) in AA women and, indeed, stage for stage, TNBC is more lethal than luminal type BCs. Why AA women are more likely to develop TNBC remains a major question. In the past, disparities in BC outcomes were frequently attributed to socioeconomic factors, but increasing data suggests that it is based on intrinsic differences in AA breast tissue compared with EW. Risk factors for BC have been extensively investigated and include elements impacting breast differentiation and development, including timing of thelarche and menarche, as well as timing and number of pregnancies. Breast formation (thelarche) occurs in AA girls 2 years earlier than EW girls in the US. The purpose of this study was to better understand the etiology of premature thelarche and, by extension, BC etiology in AA women. We utilized a unique tissue engineering system that our laboratory has developed for culture of human breast epithelial cells, both normal and malignant. This system allows for long-term (&gt;3 months) growth of normal primary epithelial cell cultures. These cultures form 3-dimensional “epispheres,” made up of 40-100 epithelial cells, which can then differentiate into organotypic branching ducts and lobules. We have established explant cultures of normal breast epithelial cells from 48/48 non-diseased women undergoing breast reduction mammoplasty. Twelve of these (25%) were AA women socioeconomically matched with the EW women. Analysis of these cultures resulted in a significant multivariate model for the timing of ductal formation (P = 0.005) involving only the ancestry of the donor and her height. Thus, intrinsic biological differences exist between AA and EW breast tissue that might impact upon the incidence or etiology of BC. We hypothesized that stem cells from AA women would be present in higher proportions or alternatively demonstrate higher potency than EW. Breast epithelial stem cells were defined by the absence of CD24 antigen and the presence of CD44 and CD49f antigens on the cell surface using quantitative flow cytometric analysis. Cloning efficiency, defined as sorted single cells that grew into colonies, was quantified as a percentage of the total cells sorted and verified microscopically. Potency, defined as colonies that exhibited multiple cell types, was quantified as a percentage of the total cloning efficiency. Our results indicate that AA samples, on average, contained 48.4% breast stem cells, while EW samples manifested a significantly smaller proportion, only 7.2% (P = 0.018). Cloning efficiency and potency analyses are currently ongoing. In summary AA women display higher proportions of stem cells in normal breast tissues relative to EW, which may be pertinent to premature thelarche and by extension, triple negative breast cancer etiology.

Citation Format: Omar Ibrahim, Stephen G. Grant, Nicole T. Myers, Amie B. Courtney, Nancy A. lalanne, Jean J. Latimer. Analysis of stem cell number & potency in African-American breast tissue. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr C26.

CURRENT STATUS AND OUTLOOK OF RENEWABLE ENERGY DEVELOPMENT IN NIGERIA

Over 80% of the current Nigerian primary energy consumption is met by petroleum. This overdependence on fossil fuels derived from petroleum for local consumption requirements should be a serious source of concern for the country in two ways – depletion of the resources and negative impact on the environment. This paper presents a critical review of the available renewable energy resources in Nigeria, namely; biomass, hydropower, solar and wind energy. It examines the current energy situation in the country and equally discusses the various energy policy documents developed by the government. Using the scenario-based International Atomic Energy Agency models, the projected energy demand and supply structure of the country through 2030 are presented and analysed. Overall, this study shows that Nigeria will overcome her present energy crisis if she explores the abundant renewable energy resources in the country.  The data presented in this paper is a crucial eye-opener for relevant government agencies towards developing these energy resources in tackling the present energy crisis in Nigeria.  http://dx.doi.org/10.4314/njt.v36i1.25

Abstract 3589: Nucleotide excision repair is elevated in stage IV commonly used breast cancer cell lines as compared to stage I breast tumor explants

Genomic instability is a hallmark of human carcinogenesis. We have previously published that sporadic stage I breast tumors exhibit deficient Nucleotide Excision Repair (NER) capacity relative to non-diseased breast reduction primary cultures (Latimer et al., 2010). In the present work, we hypothesized that this feature of early human breast cancer would not be maintained in cell lines established from late stage tumors. Our objective was to determine functional NER capacity and relative NER gene expression in a series of commonly used stage IV breast cancer-derived cell lines relative to stage I breast cancer explants and cell lines. NER capacity was determined using the functional unscheduled DNA synthesis (UDS) assay in six established breast cancer cell lines (MCF-7, MCF-7LY2, MDA-MB-231, SK-BR-3, CAMA-1, BT-20). JL BTL-12 (Jean Latimer Breast Tumor Line-12), derived from a stage III breast tumor, was included to represent an advanced stage tumor cell line established using our culture system. The NER capacity of the cell lines was compared to that of 19 stage I breast tumor primary cultures. NER gene expression was determined by expression microarray using the Affymetrix HG U-133 plus 2.0 chip in five of these established cell lines (MCF-7, MDA-MB-231, SK-BR-3, CAMA-1, BT-20), JL BTL-12 and a representative stage I tumor-derived cell line (JL BTL-8, Breast Tumor Line-8). The stage IV cell lines and JL BTL-12 all manifested significantly higher NER capacity than explants of stage I breast cancer. Unsupervised as well as supervised analyses, based on expression of the canonical 20 NER genes, placed JL BTL-12 and the five stage IV commercial cell lines in one cluster, while JL BTL-8 clustered separately. Four NER genes were significantly upregulated in JL BTL-12 and all commercial cell lines relative to JL BTL-8. In conclusion, based on NER these five cell lines commonly used in breast cancer research are more representative of late stage disease than early stage breast cancer, regardless of the type of breast cancer they represent. The most commonly diagnosed stage of breast cancer in the U.S. is now stage I, and it is now possible to study stage I cell lines or explants.

Citation Format: Homood As Sobeai, Jennifer M. Johnson, Nancy Lalanne, Omar Ibrahim, Stephen G. Grant, Sharon L. Wenger, Jean J. Latimer. Nucleotide excision repair is elevated in stage IV commonly used breast cancer cell lines as compared to stage I breast tumor explants. [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 3589.

Abstract 1552: Nucleotide excision repair gene expression in childhood acute lymphocytic leukemia is a predictor of early relapse

Double strand break repair and its relationship with genomic instability have been well studied in Acute Lymphocytic Leukemia (ALL). In contrast, base repair mechanisms, such as Nucleotide Excision Repair (NER) have not been well characterized in ALL. The NER pathway addresses base damage resulting in helix distortion and replication stalling, making it important for all types of cancer. Since increased NER is a known mechanism of chemotherapeutic drug resistance, we hypothesize that there will be an increase in the expression of the NER genes at the time of relapse in ALL patients. We have studied the role of NER in ALL by secondary analysis of 2 independent gene expression microarray studies performed by Staal et al. (Set A, GSE18497) and Hogan et al. (Set B, GSE28460). Both studies analyzed matched samples of ALL patients at diagnosis and relapse (41 and 49 pairs, respectively). In Set A we found that 17/20 NER genes have higher expression at the time of relapse, than at the time of diagnosis. 4 of these genes were individually significant. However, in a subset analysis of these data sets, based on the time to relapse, patients who have early (&lt;3 years) vs. late (&gt;3 years) relapse gave distinct results. In Set A, 18/20 NER genes were upregulated at the time of diagnosis in the early relapse group vs. the late relapse group. 4 genes were individually significantly increased. In set B, NER gene expression at the time of diagnosis of patients in the early relapse group was increased in all 20 NER genes when compared to the late relapse group. 7 genes showed individually significant increases in expression. In addition patients in the late relapse group showed an increase in expression of many of the NER genes at time of relapse when compared to time of diagnosis. In conclusion, there are two types of ALL. Early relapsing ALL manifests high NER gene expression at diagnosis with little change at relapse. Late relapsing ALL manifests low NER gene expression at diagnosis with substantial increase at the time of relapse. NER gene expression at the time of diagnosis may allow us to predict which patients are at greatest risk for earlier relapse. This will allow pharmacogenomic targeting of each type of ALL.

Citation Format: Omar Ibrahim, Homood As Sobeai, Stephen G. Grant, Jean J. Latimer. Nucleotide excision repair gene expression in childhood acute lymphocytic leukemia is a predictor of early relapse. [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 1552.