The intersection of video capsule endoscopy and artificial intelligence: addressing unique challenges using machine learning

Introduction

Technical burdens and time-intensive review processes limit the practical utility of video capsule endoscopy (VCE). Artificial intelligence (AI) is poised to address these limitations, but the intersection of AI and VCE reveals challenges that must first be overcome. We identified five challenges to address. Challenge #1: VCE data are stochastic and contains significant artifact. Challenge #2: VCE interpretation is cost-intensive. Challenge #3: VCE data are inherently imbalanced. Challenge #4: Existing VCE AIMLT are computationally cumbersome. Challenge #5: Clinicians are hesitant to accept AIMLT that cannot explain their process.

Methods

An anatomic landmark detection model was used to test the application of convolutional neural networks (CNNs) to the task of classifying VCE data. We also created a tool that assists in expert annotation of VCE data. We then created more elaborate models using different approaches including a multi-frame approach, a CNN based on graph representation, and a few-shot approach based on meta-learning.

Results

When used on full-length VCE footage, CNNs accurately identified anatomic landmarks (99.1%), with gradient weighted-class activation mapping showing the parts of each frame that the CNN used to make its decision. The graph CNN with weakly supervised learning (accuracy 89.9%, sensitivity of 91.1%), the few-shot model (accuracy 90.8%, precision 91.4%, sensitivity 90.9%), and the multi-frame model (accuracy 97.5%, precision 91.5%, sensitivity 94.8%) performed well.

Discussion

Each of these five challenges is addressed, in part, by one of our AI-based models. Our goal of producing high performance using lightweight models that aim to improve clinician confidence was achieved.

Quantitative Morphometry and Machine Learning Model to Explore Duodenal and Rectal Mucosal Tissue of Children with Environmental Enteric Dysfunction

Environmental enteric dysfunction (EED) is a subclinical enteropathy prevalent in resource-limited settings, hypothesized to be a consequence of chronic exposure to environmental enteropathogens, resulting in malnutrition, growth failure, neurocognitive delays, and oral vaccine failure. This study explored the duodenal and colonic tissues of children with EED, celiac disease, and other enteropathies using quantitative mucosal morphometry, histopathologic scoring indices, and machine learning-based image analysis from archival and prospective cohorts of children from Pakistan and the United States. We observed villus blunting as being more prominent in celiac disease than in EED, as shorter lengths of villi were observed in patients with celiac disease from Pakistan than in those from the United States, with median (interquartile range) lengths of 81 (73, 127) µm and 209 (188, 266) µm, respectively. Additionally, per the Marsh scoring method, celiac disease histologic severity was increased in the cohorts from Pakistan. Goblet cell depletion and increased intraepithelial lymphocytes were features of EED and celiac disease. Interestingly, the rectal tissue from cases with EED showed increased mononuclear inflammatory cells and intraepithelial lymphocytes in the crypts compared with controls. Increased neutrophils in the rectal crypt epithelium were also significantly associated with increased EED histologic severity scores in duodenal tissue. We observed an overlap between diseased and healthy duodenal tissue upon leveraging machine learning image analysis. We conclude that EED comprises a spectrum of inflammation in the duodenum, as previously described, and the rectal mucosa, warranting the examination of both anatomic regions in our efforts to understand and manage EED.

Home-based cardiac rehabilitation can reduce anxiety and depression in heart failure patients

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): This work was financially supported by the project POCI-01-0145-FEDER-030011, funded by FEDER, through COMPETE2020-POCI, and by national funds, through FCT/MCTES (PTDC/MEC-CAR/30011/2017). CIAFEL, UnIC and UMIB are supported by national funds through Fundação para a Ciência e Tecnologia, I.P. [(UIDB/00617/2020), (UIDB/00051/2020 and UIDP/00051/2020), and (UIDB/00215/2020 and UIDP/00215/2020), respectively]. CS received an individual grant from CAPES [BEX 0554/14-6].

Introduction

The current COVID-19 pandemic has led to significant changes in physical and mental health and has become a major challenge for cardiac rehabilitation (CR) programs. CR is an essential component in the treatment of heart failure (HF), as it improves cardiorespiratory fitness and quality of life, as well as reducing hospitalization rates. COVID-19 pandemic increased social isolation, and the CR centers were closed. Center-based CR requires the patient to travel to the hospital, which increases the risk of SARS-CoV-2 infection in this high-risk population. In this context, home-based CR can be an excellent strategy to reduce the physical and mental consequences of the social isolation imposed by the COVID-19 pandemic.

Objective

To test the effectiveness of a home-based CR program on cardiorespiratory fitness and anxiety and depression levels in individuals with HF during covid-19 pandemic.

Methods

Forty-two individuals with HF (age: 61.3±12.0; LVEF: 37.5±11.2) were included in this study. The exercise training program consisted in 12 weeks of combined exercise training (2x/week; 60min/day, 60-80% VO2peak), with 4 supervised exercise sessions in the hospital context and the remaining at home. Patients were monitored using a heart rate monitor and weekly phone calls. The following parameters were evaluated: cardiorespiratory fitness through the 6-minute walk test (6MWT) and anxiety and depression levels through the Hospital Anxiety and Depression Scale (HADS).

Results

After the home-based CR program, there was a significant increase in the 6MWT of 49 meters (95%IC: 38 to 60; p<0.001) and a significant decrease in anxiety levels of -1.12 points (95%CI: - 2.163 to -0.075 p=0.036). No significant changes were found in depression levels (p=0.954). Furthermore, the improvements in cardiorespiratory fitness were significantly associated with the reduction in the levels of anxiety (r= -0.281; p=0.028) and depression (r=: -0.278; p=0.030).

Conclusions

The home-based CR program was able to improve cardiorespiratory fitness and this improvement was associated with a decrease in anxiety and depression levels in individuals with HF. The results suggest that home-based CR can be an important strategy to minimize the physical and mental impact induced by social isolation imposed by COVID-19 pandemic in HF patients.

Impact of a home-based cardiac rehabilitation program in heart failure during the COVID-19 pandemic

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): This work was financially supported by the project POCI-01-0145-FEDER-030011, funded by FEDER, through COMPETE2020-POCI, and by national funds, through FCT/MCTES (PTDC/MEC-CAR/30011/2017). CIAFEL, UnIC and UMIB are supported by national funds through Fundação para a Ciência e Tecnologia, I.P. [(UIDB/00617/2020), (UIDB/00051/2020 and UIDP/00051/2020), and (UIDB/00215/2020 and UIDP/00215/2020), respectively]. CS received an individual grant from CAPES [BEX 0554/14-6].

Introduction

Cardiac rehabilitation (CR) is an evidence-based recommended treatment of heart failure (HF) patients. During the COVID-19 pandemic, the shutdown of CR centers was necessary to limit the infection risk among high-risk patients. The integration of a home-based CR (HBCR) program in CR units can help to improve the delivery of care and improve cardiovascular outcomes of HF patients.

Purpose

To assess the effectiveness of an HBCR program in HF patients.

Methods

This is a sub­study of the EXercise InTervention in Heart Failure trial (EXIT-HF), which include forty-nine HF patients (preserved and reduced ejection fraction). The HBCR program consisted in 12-week combined exercise program (60%-80% of peak oxygen consumption (VO2 peak)), 2 training sessions per week, for a total of 24 sessions. Patients performed 4 supervised training sessions and the remaining sessions at home. All patients performed a cardiopulmonary exercise test (VO2 peak), the 6-minute-walking test (6MWT), collected blood analysis (plasma NT-proBNP), and answered the Minnesota Living with Heart Failure Questionnaire.

Results

Forty-two patients (86%) complete at least 80% of prescribed training sessions (age: 61.1±12; FEVE: 37.1±10.8). The HBCR program improve VO2 peak from 18.3 to 20.1ml/kg/min (+1.8 ml/kg/min; 95%IC:1.4 to 2.4; p<0.001) and the walked distance at the 6MWT from 462 to 512 meters (+49 meters; 95%IC: 38 to 60; p<0.001). In addition, overall quality of life was improved (-13 points; 95%IC:-7.8 to -18.5; p<0.001), as well physical (-6.3 points; 95%IC:-3.5 to -9; p<0.001) and emotional dimension of quality of life (-2.8points ; 95%IC: -0.9 to -4.7; p=0.06). No significant change was found in NT-proBNP levels (820±1220 vs 674±903; p=0.285).

Conclusions

Our results showed that HBCR is feasible and can improve functional capacity and quality of life in HF patients.

Maternal and Child Health Pipeline Training Programs: A Description of Training Across 6 Funded Programs

Purpose

The HRSA-funded maternal and child health pipeline training programs (MCHPTPs) are a response to the critical need to diversify the MCH workforce, as a strategy to reduce health disparities in MCH populations. These MCHPTPs support students from undergraduate to graduate education and ultimately into the MCH workforce.

Description

The models and components of training across the six MCHPTPs funded in 2016–2021 are summarized, to examine the design and delivery of undergraduate pipeline training and the insights gained across programs.

Assessment

Strategies that emerged across training programs were organized into three themes: recruitment, support for student persistence (in education), and pipeline-to-workforce intentionality. Support for student persistence included financial support, mentoring, creating opportunity for students to develop a sense of belonging, and the use of research as a tool to promote learning and competitiveness for graduate education. Finally, the link to Maternal and Child Health Bureau (MCHB) long-term training and other MCHB opportunities for professional development contributed significant nuance to the pipeline-to-workforce objectives of these programs.

Conclusions

The MCHPTPs not only increase the diversity of the MCH workforce, they also actively prepare the next generation of MCH leaders. The intentional connection of undergraduates to the infrastructure and continuum of MCH training, underscores the comprehensive impact of this funding.

Impact of cardiac rehabilitation on inflammation in patients with ischaemic cardiomyopathy

Introduction

The benefits of cardiac rehabilitation (CR) in patients with ischaemic cardiomyopathy are well-known. However, inflammatory states have been associated to an increased risk of cardiovascular events.

Purpose

Evaluate the impact of CR in the serum levels of inflammatory biomarkers and identify potential predictors of that effect.

Methods

We retrospectively studied consecutive patients with ischaemic cardiomyopathy who completed a CR programme between 2011 and 2017. Patients underwent a supervised exercise training protocol, twice a week during a period of 8 to 12 weeks. Functional capacity was evaluated by metabolic equivalents assessed prior the beginning and 3 months after the programme with a symptom limited exercise treadmill test. Patients without levels of serum C-reactive protein at beginning and at the end of CR programme were excluded. Median variation of serum C-reactive protein was assessed and two groups were defined: one with levels above that and one with levels below.

Results

Of 250 patients (60.3±11.1 years, 84% male), 67% were admitted after an acute myocardial infarction. Left ventricular ejection fraction ≤40% before CR was present in 32% of individuals. Median levels of serum C-reactive protein before CR were 8.8 (3.1–21.7) mg/L and median variation after CRP was a decrease of 5.1 (0.9–17.7) mg/L (p&lt;0.001). Before CR, higher levels of serum C-reactive protein were seen in obese (15.7 [8–52.7] versus 8.8 [3.2–27.8], p=0.04) and those with higher NT-proBNP (p&lt;0.001). Patients with decrease of &gt;5.1mg/L of serum C-reactive protein had lower prevalence of hypertension (18% versus 30%, p=0.02), higher prevalence of obesity (16% versus 7%, p=0.03), lower levels of HDL cholesterol (38.3 [11.1] versus 43.2 [12.6], p&lt;0.001) and higher levels of NT-proBNP (1079 [610.3–1988] versus 488 [215–777], p&lt;0.001) at baseline. An increase of at least of 10% of functional capacity after CR was reached in 65% of patients, similar between groups. Patients with decrease of serum C-reactive protein &gt;5.1mg/L had also higher reduction of NT-proBNP after CR comparing to baseline (491.1 [142.7–948.5] versus 162.0 [30.9–295.2], p&lt;0.001).

Conclusions

Serum levels of inflammatory biomarkers decreased after CR in patients with ischaemic cardiomyopathy. Normotension, obesity, lower HDL and higher levels of natriuretic peptides are associated to a better response.

Funding Acknowledgement

Type of funding sources: None.

Machine Learning Predictive Outcomes Modeling in Inflammatory Bowel Diseases

There is a rising interest in use of big data approaches to personalize treatment of inflammatory bowel diseases (IBDs) and to predict and prevent outcomes such as disease flares and therapeutic nonresponse. Machine learning (ML) provides an avenue to identify and quantify features across vast quantities of data to produce novel insights in disease management. In this review, we cover current approaches in ML-driven predictive outcomes modeling for IBD and relate how advances in other fields of medicine may be applied to improve future IBD predictive models. Numerous studies have incorporated clinical, laboratory, or omics data to predict significant outcomes in IBD, including hospitalizations, outpatient corticosteroid use, biologic response, and refractory disease after colectomy, among others, with considerable health care dollars saved as a result. Encouraging results in other fields of medicine support efforts to use ML image analysis-including analysis of histopathology, endoscopy, and radiology-to further advance outcome predictions in IBD. Though obstacles to clinical implementation include technical barriers, bias within data sets, and incongruence between limited data sets preventing model validation in larger cohorts, ML-predictive analytics have the potential to transform the clinical management of IBD. Future directions include the development of models that synthesize all aforementioned approaches to produce more robust predictive metrics.

AB0754 THE INFLUENCE OF PHYSICAL ACTIVITY ON BODY COMPOSITION AND SELF-ESTEEM IN ADULTS WITH JUVENIL IDIOPATHIC ARTHRITIS

Background:

With improvement of treatment, long-term factors influencing quality of life have to be addressed in the care of juvenile idiopathic arthritis (JIA) patients.

Objectives:

To compare body composition, level of physical activity and self-esteem of adult patients with JIA with control group (CG).

Methods:

The levels of physical activity were analyzed using the International Physical Activity Questionnaire (IPAQ) short version. The body composition data were collected using the Omrom HBF 514 C vertical electric bioimpedance device. The Rosenberg Self-Esteem Scale was used to assess positive and negative attitude and feelings about themselves, where the lower the score, the higher the individual’s self-esteem. For the statistical analysis of the data, the IBM SPSS software was used with a significance index of p <0.05.

Results:

We included 81 individuals >18 years, 38 with JIA and 43 healthy people. The female sex was the largest participant in this research, being. There was no significant difference regarding sex [female =28 (73.7%) in JIA and 26 (60.5%) in CG] and age of the groups (29.39 ± 7.6 vs. 31.1 ± 3.1, p = 0.18). The CG showed greater height and body weight (163.5 ± 9.8 vs. 169.6 ± 8.0, p<0.001; 63.07 ± 16.65 vs. 69.33 ± 6.88, p = 0.003, respectively), but no difference in Body Mass Index (BMI) was observed (24.32 ± 4.9 vs. 24.12 ± 2.09, p = 0.8). JIA had a higher percentage of total fat mass (31.65 ± 10.20 vs. 28.47 ± 4.9, p = 0.07), while the CG had a higher percentage of total muscle mass (29.7 ± 6.5 vs. 35.86 ± 6.05, p<0.001). The self-esteem of JIA patients was lower than in the CG (21 ± 3.9 vs. 16.26 ± 4.3, p<0.001). In the IPAQ classifications, JIA patients were classified as less physically active than the CG (2.63% vs. 20.93%, p = 0.022), less irregularly active (5.26% vs. 23.25, p = 0.023) and a higher level of sedentary lifestyle (65.78% vs. 25.58%, p<0.001). A higher percentage of muscle mass was associated with greater self-esteem (r=-0.3; p=0.01).

Conclusion:

The low practice of physical activities by patients with JIA seems to directly influence both, their body composition and their self-esteem. These patients should be encouraged to increase physical activity from an early age by a multiprofessional healthcare team to seek improvement their quality of life.

Disclosure of Interests:

None declared

Clinical outcomes and trans-syndesmotic screw frequency after posterior malleolar fracture osteosynthesis

AIM

This study aimed to evaluate the clinical outcomes and the trans-syndesmotic screw frequency after trimalleolar ankle fractures with a posterior malleolus fracture involving <25% of the articular surface.

MATERIAL AND METHODS

Retrospective comparative study. Patients with trimalleolar ankle fracture who underwent surgery between January 2011 and January 2018 were identified within the departments' fracture database. General demographics, treatment details, and fracture specific details (CT-scans) were assessed. Patients were grouped per the posterior malleolus fragment treatment: osteosynthesis (group 1) and non-osteosynthesis (group 2).

RESULTS

64 patients, 58.6 ± 17.8 years (range: 23-75), 68.8% female were eligible and follow up time was 43.1 ± 22.2 (range 24-96) months. The mean size of the posterior malleolus fragment was 14.7 ± 5.3% (range: 5-24). Posterior malleolus fragment treatment distribution: osteosynthesis (group 1) 31.2% and non- osteosynthesis (group 2) 68.8%. Group 1 showed significantly better clinical outcomes (p<0.05), AOOS (93.9 ± 5.79 (range: 73-99), AOFAS (91.5 ± 6.22 (range: 72-100) and VAS (0.8 ± 1.22 (range: 0-5) compared to Group 2, AOOS (84.25±8.34 (range: 63-100); AOFAS (84.75±8.05 (range: 58-100) and VAS (1.7 ± 1.38 (range: 0-6). Osteosynthesis of the posterior malleolus fragment significantly reduced the frequency of trans-syndesmotic screw (0%) compared to non-osteosynthesis posterior malleolus fragment (15.9%) (p < 0.05). The EQ-5D score was better in group 1 (1.08±0.27 (range: 1-2.2) compared to group 2 (1.27 ± 0.27 (range: 1-2.4) but with no statistical significance (p> 0.15).

CONCLUSION

Posterior malleolus fragments (<25% of the articular surface) have significantly better clinical outcomes and significant decrease in trans-syndesmotic screw need following osteosynthesis.

Deep Learning for Whole-Slide Tissue Histopathology Classification: A Comparative Study in the Identification of Dysplastic and Non-Dysplastic Barrett's Esophagus

The gold standard of histopathology for the diagnosis of Barrett's esophagus (BE) is hindered by inter-observer variability among gastrointestinal pathologists. Deep learning-based approaches have shown promising results in the analysis of whole-slide tissue histopathology images (WSIs). We performed a comparative study to elucidate the characteristics and behaviors of different deep learning-based feature representation approaches for the WSI-based diagnosis of diseased esophageal architectures, namely, dysplastic and non-dysplastic BE. The results showed that if appropriate settings are chosen, the unsupervised feature representation approach is capable of extracting more relevant image features from WSIs to classify and locate the precursors of esophageal cancer compared to weakly supervised and fully supervised approaches.

Upgrading end-of-line residues of the red seaweed Gelidium sesquipedale to polyhydroxyalkanoates using Halomonas boliviensis

Agar extraction from Gelidium and Gracilaria red seaweed species produces hundred thousand ton of carbohydrate-rich residues annually. Gelidium sesquipedale waste biomass obtained after agar extraction, still contained 44.2 % w/w total carbohydrates (dry-weight basis). These residues were biologically up-graded to poly-3-hydroxybutyrate (P3HB) after saccharification of their carbohydrate fraction to simple sugars. A combined hydrolysis treatment using sulfamic acid followed by enzymatic hydrolysis with cellulases produced a glucose-rich hydrolysate with a negligible content of inhibitors. With this treatment a sugar yield of circa 30 % (g glucose/g biomass) was attained. The algal hydrolysates were assessed as carbon source for the production of P3HB by the halotolerant bacteria Halomonas boliviensis. A cell concentration of 8.3 g L-1 containing 41 % (w/w) of polymer and a yield (YP/S ) of 0.16 gpolymer/gglucose were attained in shake flask assays. In this work, cellulose-rich seaweed waste was shown to be an upgradable, sustainable source of carbohydrates.

P1349 POCUS by general and family physician - advancing physical examination

BACKGROUND

Alongside with the development of hand held equipment, echo is becoming more accessible to nontraditional settings. General and family medicine (GPs) are at the forefront of any health system, but the use of cardiac echo by GPs is still unexplored. PURPOSE: This study aims to evaluate the accuracy of echocardiography assessment performed as an extension of the physical exam by GPs. METHODS: Two GPs underwent standard echocardiography training for 6 months. Subsequently, patients with diabetes or arterial hypertension were submitted to an echocardiogram performed by their GPs using a pocket ultrasound. Views obtained (with and without color Doppler) were parasternal long and short axis, apical and subcostal, with measurements of the posterior wall (PW), interventricular septum (IVS), left ventricle (LV), left atrium (LA), aorta and inferior vena cava (IVC). Studies were reviewed at the workstation and measured by two experts who classified the exams according to the image quality. RESULTS: Sixty echocardiograms were analyzed (mean age of 61y, 42% females and 58% males). In 50% the image quality was considered sufficient, 42% considered good and 8% considered bad. There were statistically significant differences between the GPs and expert measurements on the sinus of Valsalva (30.3 ± 3 to 28.8 ± 3.1mm, p = 0.001), LV in systole (p &lt; 0.001, 28[24,31] for 31[29,34]mm), IVS (p = 0.001, 10.9 ± 1.7 for 10.1 ± 1.5mm), PW (p = 0.018, 8.7 ± 1.1 to 9.2 ± 1.6mm) and TAPSE (p = 0.021, 20.9 ± 2.3 to 20.1 ± 2.7mm). There were no significate differences in the measurements of the ascending aorta, LA, LV in diastole and IVC. Agreement between the GPs and the experts was moderate for the evaluation of LVH (k = 0.48). The concordance was substantial for evaluation of LV function (k = 0.66) and excellent for evaluation of pericardial effusion (k = 1) and right ventricular function (k = 1). Concordance was excellent for mitral insufficiency (k = 0.83) and substantial for aortic insufficiency (k = 0.68) and tricuspid insufficiency (k = 0.61). A case of mitral stenosis was identified by both. GPs signalized a case of mild aortic stenosis that the expert did not consider. CONCLUSION: GPs trained in echocardiography, using pocket ultrasound, can obtain cardiac images with sufficient quality for interpretation by experts in the majority of cases. In this study, differences in dimensions might be explained by interobserver variability and/or by the performance of measurements in different environments, mobile vs workstation. Overall the differences were minor and clinically meaningless.

Integrating road traffic externalities through a sustainability indicator

Road traffic poses negative externalities on society and represents a key challenge in sustainable transportation. However, the existing literature about the assessment of traffic externalities drawn on a common measure is scarce. This paper develops a sustainability indicator that integrates traffic-related externalities as means of traffic congestion, noise, greenhouse gases (GHG) and nitrogen oxides emissions, health impacts and road crash related costs, and adjusted to local contexts of vulnerability. Traffic, road crashes, acoustic and vehicle dynamic data were collected from one real-world intercity corridor pair comprising three alternative routes. The site-specific operations were characterized using a modeling platform of traffic, emissions, noise and air quality. A specific methodology is applied for each road traffic externality and translated in a single factor - external cost. The results indicated that road crashes presented the largest share in the partly rural/urban route while GHG emissions had the highest contribution in external costs for the highway routes. Also, the distribution of external cost component varied according to the type of road, mostly due to different levels of exposed inhabitants. This paper offers a line of research that produced a method for decision-makers with a reliable and flexible cost analysis aimed at reducing the negative impacts of road traffic. It also encourages the design of eco-traffic management policies considering the perspective of drivers, commuters and population.

A 24-hour perioperative case study on argatroban use for left ventricle assist device insertion during cardiopulmonary bypass and veno-arterial extracorporeal membrane oxygenation

A 44-year-old male with ongoing chest pain and left ventricular ejection fraction <20% was transferred from a peripheral hospital with intra-aortic balloon pump placement following a non-ST-elevation myocardial infarction (STEMI). The patient underwent emergent multi-vessel coronary artery bypass grafting requiring veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) on post-operative day (POD)#9 secondary to cardiogenic shock with biventricular failure. Due to clot formation, an oxygenator change-out was necessary shortly after initiation. Following a positive heparin-induced thrombocytopenia (HIT) assay, a total circuit exchange was required to eliminate all heparin coating and argatroban was deemed the anticoagulant of choice due to acute kidney injury. On POD#24, the decision was made to implant a left ventricle assist device (LVAD) as a bridge to heart transplantation. There was difficulty achieving an activated clotting time (ACT) >400 s: multiple argatroban bolus doses were required, along with accelerated up-titration of infusion dosing. Despite maintaining an ACT >484 s, clot formation was observed in the cardiotomy reservoir prior to separation. Subsequently, the patient developed severe disseminated intravascular coagulopathy, with both intra-cardiac and intravascular thrombi, requiring massive transfusion and continuous cell saving due to severe hemorrhage post cardiopulmonary bypass (CPB). The patient received a total of 105 units of plasma, 74 units of packed red cells, 19 units of platelets, 13 bottles of 5% albumin, 6 units of cryoprecipitate and 2 doses of factor VIIa intraoperatively over the course of 24 hours. A total of 19.7 L of washed red blood cells were returned to the patient from the cell saver. With the LVAD in place, the patient developed transfusion-related acute lung injury and acute respiratory distress syndrome with right ventricular dysfunction requiring VA ECMO once again. On POD#30, ECMO was discontinued and the patient was discharged from the intensive care unit (ICU) on POD 66. After a very complex post-operative stay with numerous surgeries and extensive rehabilitation, the patient was discharged home with the LVAD on POD#112.

Whole body perfusion strategy for aortic arch repair under moderate hypothermia

INTRODUCTION

Aortic arch reconstruction under moderate hypothermia is commonly performed with antegrade cerebral perfusion (ACP) for brain protection; however, hypothermia alone is often solely relied upon for visceral and lower body protection. We investigated whether the addition of simultaneous lower body perfusion to ACP (whole body perfusion - WBP) may ameliorate the metabolic derangements of moderate hypothermic circulatory arrest (MHCA).

METHODS

Between 2008 and 2014, 106 consecutive patients underwent elective or emergent aortic arch surgery with MHCA, with either ACP only (44 patients, 66±12 years, 30% female) or WBP (62 patients, 61±15 years, 31% female). Primary outcomes included 30-day/in-hospital mortality, intensive care unit (ICU) and hospital lengths of stay (LOS) and specific parameters of metabolic recovery.

RESULTS

There were no significant differences between the groups in 30-day/in-hospital mortality (ACP: 3 (6.8%), WBP: 2 (3.2%); p=0.65), stroke (ACP: 1 (2.3%), WBP: 1 (1.6%); p=1.0) or renal failure (ACP: 2 (4.5%), WBP: 1 (1.5%); p=0.57). In the WBP group, we identified a significant reduction in lactate level at ICU admission (ACP 5.5 vs. WBP 3.5 mmol/L; p=0.002), time to lactate normalization (p=0.014) and median ICU length-of-stay (ACP 3 vs. WBP 1 days; p=0.049). There was no difference in post-operative creatinine (ACP: 104, WBP: 107 μmol/L; p=0.66). After multivariable regression adjustment, perfusion strategy no longer remained an independent predictor of ICU discharge time (p=0.09), however, cardiopulmonary bypass time (p=0.02), age (p=0.012) and emergent surgery (p=0.02) were.

CONCLUSIONS

A WBP strategy during aortic arch reconstruction with MHCA may be associated with more rapid normalization of metabolic parameters and reduced ICU length of stay compared to using ACP alone. Further evaluation with a randomized trial is warranted.

Relationship between oro and nasopharynx permeability and the direction of facial growth

AIM

Most scientific literature relates vertical growth to individuals with decreased upper airway permeability. However, we often find subjects with a long face and a normal breathing pattern, most likely caused by other aetiological factors. And, frequently, we also find decreased upper airway permeability with horizontal growth. The aim of the study was to compare the cephalometric measurements of the oro and nasopharynx permeability with the facial growth direction and to identify the most common facial growth direction in individuals with decreased upper airway permeability.

MATERIALS AND METHODS

Cephalometric analysis was carried out in 158 pre-adolescent patients at the Orthodontic appointment, using facial profile teleradiographs. Parameters used were Jabarak's ratio and measurement of oro-nasopharynx space. Data collected were submitted to statistical treatment.

RESULTS

This study points to the presence of an intermediate growth in individuals with diminished oro and nasopharynx permeability, either simultaneous or separate. The number of individuals with diminished permeability and vertical growth is close to the number of individuals with horizontal growth.

CONCLUSIONS

The individuals with diminished permeability of the upper airway present an intermediate growth direction, representing the most frequent type. In the less common growth directions, there is a slight tendency to horizontal facial growth verified in individuals with diminished nasopharynx permeability. Also, a light tendency to vertical facial growth is present when oropharynx permeability is reduced.

Whole body perfusion for hybrid aortic arch repair: evolution of selective regional perfusion with a modified extracorporeal circuit

BACKGROUND

Patients undergoing hybrid aortic arch reconstruction require careful protection of vital organs. We believe that whole body perfusion with tailored dual circuitry may help to achieve optimal patient outcomes.

METHODS

Our circuit has evolved from a secondary circuit utilizing a cardioplegia delivery device for lower body perfusion to a dual-oxygenator circuit. This allows individually controlled regional perfusion with ease of switching from secondary to primary circuit for total body flow. The re-design allows for separate flow and temperature regulation with two oxygenators in parallel. All patients underwent a single-stage operation for simultaneous treatment of arch and descending aortic pathology via a sternotomy, using a hybrid frozen elephant trunk technique.

RESULTS

We report six consecutive patients undergoing hybrid arch and frozen elephant trunk reconstruction using a dual-oxygenator circuit. Five patients underwent elective surgery and one was emergent. One patient had an acute dissection while three underwent concomitant procedures, including a Ross procedure and two valve-sparing root reconstructions. Three cases were redo sternotomies. The mean pump time was 358 ± 131 min, the aortic cross clamp time 243 ± 135 min, the cardioplegia volume of 33,208 ml ± 16,173, cerebral ischemia 0 min, lower body ischemia 76 ± 34 min and the average lower body perfusion time was 142 min. Two patients did not require any donor blood products. The median intensive care unit (ICU) and hospital lengths of stay (LOS) were two days and 10 days, respectively. The average peak serum lactate on CPB was 7.47 mmol/L and, at admission to the ICU, it was 3.37 mmol/L. Renal and respiratory failure developed in the salvage acute type A dissection patient. No other complications occurred in this series.

CONCLUSIONS

Whole body perfusion as delivered through individually controlled dual-oxygenator circuitry allows maximum flexibility for hybrid aortic arch reconstruction. A modified circuit perfusion strategy may help to limit intra-operative metabolic derangements, providing improved clinical outcomes.

Women Suffering through Their Bodies

This article is concerned with the nature of suffering as experienced by women struggling with problems related to the body. Since the body is viewed as integral in the formation of a woman's identity and self-concept, any illness, ailment, or deficiency associated with it may lead her to experience pain and suffering. To explore meanings of personal suffering, three contexts were chosen, namely familial breast cancer, eating disorders, and infertility. A qualitative approach, using the case study method, was adopted to provide rich descriptions of the different experiences of suffering. In-depth interviews were conducted with women living with familial breast cancer, eating disorders, and infertility. Two women were chosen for each context. The results show that for these women suffering manifested as loss, isolation, loneliness, anger, and emptiness. Suffering encompassed the physical, emotional, and social spheres, and entailed a deep and complex experience of pain. It was also evident that suffering remains a personal issue that depends on a person's life circumstances, personality, past and present experiences, the problem at hand, and the surrounding environment.

Hydrogen sensing via anomalous optical absorption of palladium-based metamaterials

A palladium (Pd)-based optical metamaterial has been designed, fabricated and characterized for its application in hydrogen sensing. The metamaterial can replace Pd thin films in optical transmission schemes for sensing with performances far superior to those of conventional sensors. This artificial material consists of a palladium-alumina metamaterial fabricated using inexpensive and industrial-friendly bottom-up techniques. During the exposure to hydrogen, the system exhibits anomalous optical absorption when compared to the well-known response of Pd thin films, this phenomenon being the key factor for the sensor sensitivity. The exposure to hydrogen produces a large variation in the light transmission through the metamembrane (more than 30% with 4% in volume hydrogen-nitrogen gas mixture at room temperature and atmospheric pressure), thus avoiding the need for sophisticated optical detection systems. An optical homogenization model is proposed to explain the metamaterial response. These results contribute to the development of reliable and low-cost hydrogen sensors with potential applications in the hydrogen economy and industrial processes to name a few, and also open the door to optically study the hydrogen diffusion processes in Pd nanostructures.

Differential expression of key regulators of Toll-like receptors in ulcerative colitis and Crohn's disease: a role for Tollip and peroxisome proliferator-activated receptor gamma?

The innate immune system is currently seen as the probable initiator of events which culminate in the development of inflammatory bowel disease (IBD) with Toll-like receptors (TLRs) known to be involved in this disease process. Many regulators of TLRs have been described, and dysregulation of these may also be important in the pathogenesis of IBD. The aim of this study was to perform a co-ordinated analysis of the expression levels of both key intestinal TLRs and their inhibitory proteins in the same IBD cohorts, both ulcerative colitis (UC) and Crohn's disease (CD), in order to evaluate the potential roles of these proteins in the pathogenesis of IBD. Of the six TLRs (TLRs 1, 2, 4, 5, 6 and 9) examined, only TLR-4 was increased significantly in IBD, specifically in active UC. In contrast, differential alterations in expression of TLR inhibitory proteins were observed. A20 and suppressor of cytokine signalling 1 (SOCS1) were increased only in active UC while interleukin-1 receptor-associated kinase 1 (IRAK-m) and B cell lymphoma 3 protein (Bcl-3) were increased in both active UC and CD. In contrast, expression of both peroxisome proliferator-activated receptor gamma (PPARγ) and Toll interacting protein (Tollip) was decreased in both active and inactive UC and CD and at both mRNA and protein levels. In addition, expression of both PPARγ and A20 expression was increased by stimulation of a colonic epithelial cell line Caco-2 with both TLR ligands and commensal bacterial strains. These data suggest that IBD may be associated with distinctive changes in TLR-4 and TLR inhibitory proteins, implying that alterations in these may contribute to the pathogenesis of IBD.

Surgical treatment of bronchiectasis: A review of 20 years of experience

BACKGROUND

Bronchiectasis is defined as an abnormal and irreversible dilation and distortion of the bronchi, which has numerous causes. Surgical treatment of this disease is usually reserved for focal disease and when the medical treatment is no longer effective. We report our center experience and outcomes in bronchiectasis surgery during the last 20 years.

METHODS

Between 1994 and 2014, sixty-nine patients underwent surgical resection for bronchiectasis. Patient demographics, presenting symptoms, indications for surgical treatment, type of lung resection, morbidity and mortality, as well as clinical follow-up and outcomes were analyzed.

RESULTS

From the 69 patients included, 31 (44.9%) were male and 38 (55.1%) were female. Surgery was indicated because of unsuccessful medical therapy in 33 patients (47.8%), haemoptysis in 22 patients (31.9%), nondiagnostic lung mass in 9 patients (13.0%) and lung abscess in 5 patients (7.3%). The surgical procedures were lobectomy in 45 (65.2%) patients, pneumonectomy in 10 (14.5%) patients, bilobectomy in 8 (11.6%) patients, lobectomy plus segmentectomy in 3 (4.3%) patients and only segmentectomy in 3 (4.3%) patients. Morbidity rate was 14.5% and there was no perioperative mortality. The follow-up was possible in 60 patients, with an outcome reported as excellent in 44 (73.3%) patients, as improved in 11 (18.3%) and as unchanged in 5 (8.3%).

CONCLUSION

Although the number of patients with bronchiectasis referred for surgical treatment has decreased, pulmonary resection still plays a significant role. Surgical resection of localized bronchiectasis is a safe procedure with proven improvement of quality of life for the majority of patients.

Increased titer and reduced lactate accumulation in recombinant retrovirus production through the down-regulation of HIF1 and PDK

Many mammalian cell lines used in the manufacturing of biopharmaceuticals exhibit high glycolytic flux predominantly channeled to the production of lactate. The accumulation of lactate in culture reduces cell viability and may also decrease product quality. In this work, we engineered a HEK 293 derived cell line producing a recombinant gene therapy retroviral vector, by down-regulating hypoxia inducible factor 1 (HIF1) and pyruvate dehydrogenase kinase (PDK). Specific productivity of infectious viral titers could be increased more than 20-fold for single gene knock-down (HIF1 or PDK) and more than 30-fold under combined down-regulation. Lactate production was reduced up to 4-fold. However, the reduction in lactate production, alone, was not sufficient to enhance the titer: high-titer clones also showed significant enrollment of metabolic routes not related to lactate production. Transcriptome analysis indicated activation of biological amines metabolism, detoxification routes, including glutathione metabolism, pentose phosphate pathway, glycogen biosynthesis and amino acid catabolism. The latter were validated by enzyme activity assays and metabolite profiling, respectively. High-titer clones also presented substantially increased transcript levels of the viral genes expression cassettes. The results herein presented demonstrate the impact of HIF1 and PDK down-regulation on the production performance of a mammalian cell line, reporting one of the highest fold-increase in specific productivity of infectious virus titers achieved by metabolic engineering. They additionally highlight the contribution of secondary pathways, beyond those related to lactate production, that can be also explored to pursue improved metabolic status favoring a high-producing phenotype.

Evaluation of helper-dependent canine adenovirus vectors in a 3D human CNS model

Gene therapy is a promising approach with enormous potential for treatment of neurodegenerative disorders. Viral vectors derived from canine adenovirus type 2 (CAV-2) present attractive features for gene delivery strategies in the human brain, by preferentially transducing neurons, are capable of efficient axonal transport to afferent brain structures, have a 30-kb cloning capacity and have low innate and induced immunogenicity in preclinical tests. For clinical translation, in-depth preclinical evaluation of efficacy and safety in a human setting is primordial. Stem cell-derived human neural cells have a great potential as complementary tools by bridging the gap between animal models, which often diverge considerably from human phenotype, and clinical trials. Herein, we explore helper-dependent CAV-2 (hd-CAV-2) efficacy and safety for gene delivery in a human stem cell-derived 3D neural in vitro model. Assessment of hd-CAV-2 vector efficacy was performed at different multiplicities of infection, by evaluating transgene expression and impact on cell viability, ultrastructural cellular organization and neuronal gene expression. Under optimized conditions, hd-CAV-2 transduction led to stable long-term transgene expression with minimal toxicity. hd-CAV-2 preferentially transduced neurons, whereas human adenovirus type 5 (HAdV5) showed increased tropism toward glial cells. This work demonstrates, in a physiologically relevant 3D model, that hd-CAV-2 vectors are efficient tools for gene delivery to human neurons, with stable long-term transgene expression and minimal cytotoxicity.

Salvaging catastrophe in transcatheter aortic valve implantation: rehearsal, preassigned roles, and emergency preparedness

PURPOSE

Emergency rescue plans for acute complications during transcatheter aortic valve implantation (TAVI) commonly include cardiopulmonary resuscitation, femoro-femoral cardiopulmonary bypass (CPB), and hemodynamic stabilization before definitive intervention is achieved. Nevertheless, most cases of emergency resuscitation remain chaotic and disorganized and often take longer than necessary, even in experienced centres. We sought to determine which factors and procedures may be associated with improved patient outcomes when emergencies arise during TAVI.

SOURCES

MEDLINE(®) and EMBASE™ were searched with the following key words: "TAVI" or "TAVR" or "transcatheter valve implantation" or "transcatheter valve replacement" and "emergency cardiac surgery" or "conversion". Two hundred seventeen articles met the criteria and were reviewed.

PRINCIPAL FINDINGS

Utilization of a formal emergency checklist by a multidisciplinary TAVI team may reduce procedural errors, smooth the transition to CPB, and ultimately speed the delivery of corrective measures including emergency cardiac surgery.

CONCLUSION

A well-organized regularly-rehearsed emergency rescue plan that preassigns resuscitative roles may shorten the duration of patient instability and resuscitation and improve patient outcomes when catastrophe occurs in TAVI. The anesthesia team plays a central role in preventing, detecting, and treating intraprocedural complications during TAVI.

On-chip sample preparation and analyte quantification using a microfluidic aqueous two-phase extraction coupled with an immunoassay

Immunoassays are fast and sensitive techniques for analyte quantification, and their use in point-of-care devices for medical, environmental, and food safety applications has potential benefits of cost, portability, and multiplexing. However, immunoassays are often affected by matrix interference effects, requiring the use of complex laboratory extraction and concentration procedures in order to achieve the required sensitivity. In this paper we propose an integrated microfluidic device for the simultaneous matrix clean-up, concentration and detection. This device consists of two modules in series, the first performing an aqueous two-phase extraction (ATPE) for matrix extraction and analyte pre-concentration, and the second an immunoassay for quantification. The model analyte was the mycotoxin ochratoxin A (OTA) in a wine matrix. Using this strategy, a limit of detection (LoD) of 0.26 ng mL(-1) was obtained for red wine spiked with OTA, well below the regulatory limit for OTA in wines of 2 ng mL(-1) set by the European Union. Furthermore, the linear response on the logarithmic concentration scale was observed to span 3 orders of magnitude (0.1-100 ng mL(-1)). These results are comparable to those obtained for the quantification of OTA in plain buffer without an integrated ATPE (LoD = 0.15 ng mL(-1)). The proposed method was also found to provide similar results for markedly different matrices, such as red and white wines. This novel approach based on aqueous two-phase systems can help the development of point-of-care devices that can directly deal with real samples in complex matrices without the need for extra extraction processes and equipment.

Impact of adenovirus life cycle progression on the generation of canine helper-dependent vectors

Helper-dependent adenovirus vectors (HDVs) are safe and efficient tools for gene transfer with high cloning capacity. However, the multiple amplification steps needed to produce HDVs hamper a robust production process and in turn the availability of high-quality vectors. To understand the factors behind the low productivity, we analyzed the progression of HDV life cycle. Canine adenovirus (Ad) type 2 vectors, holding attractive features to overcome immunogenic concerns and treat neurobiological disorders, were the focus of this work. When compared with E1-deleted (ΔE1) vectors, we found a faster helper genome replication during HDV production. This was consistent with an upregulation of the Ad polymerase and pre-terminal protein and led to higher and earlier expression of structural proteins. Although genome packaging occurred similarly to ΔE1 vectors, more immature capsids were obtained during HDV production, which led to a ~4-fold increase in physical-to-infectious particles ratio. The higher viral protein content in HDV-producing cells was also consistent with an increased activation of autophagy and cell death, in which earlier cell death compromised volumetric productivity. The increased empty capsids and earlier cell death found in HDV production may partially contribute to the lower vector infectivity. However, an HDV-specific factor responsible for a defective maturation process should be also involved to fully explain the low infectious titers. This study showed how a deregulated Ad cycle progression affected cell line homeostasis and HDV propagation, highlighting the impact of vector genome design on virus-cell interaction.