Variability of computational fluid dynamics solutions for pressure and flow in a giant aneurysm: the ASME 2012 Summer Bioengineering Conference CFD Challenge.

Stimulated by a recent controversy regarding pressure drops predicted in a giant aneurysm with a proximal stenosis, the present study sought to assess variability in the prediction of pressures and flow by a wide variety of research groups. In phase I, lumen geometry, flow rates, and fluid properties were specified, leaving each research group to choose their solver, discretization, and solution strategies. Variability was assessed by having each group interpolate their results onto a standardized mesh and centerline. For phase II, a physical model of the geometry was constructed, from which pressure and flow rates were measured. Groups repeated their simulations using a geometry reconstructed from a micro-computed tomography (CT) scan of the physical model with the measured flow rates and fluid properties. Phase I results from 25 groups demonstrated remarkable consistency in the pressure patterns, with the majority predicting peak systolic pressure drops within 8% of each other. Aneurysm sac flow patterns were more variable with only a few groups reporting peak systolic flow instabilities owing to their use of high temporal resolutions. Variability for phase II was comparable, and the median predicted pressure drops were within a few millimeters of mercury of the measured values but only after accounting for submillimeter errors in the reconstruction of the life-sized flow model from micro-CT. In summary, pressure can be predicted with consistency by CFD across a wide range of solvers and solution strategies, but this may not hold true for specific flow patterns or derived quantities. Future challenges are needed and should focus on hemodynamic quantities thought to be of clinical interest.

Abnormal CTLA-4 function in T cells from patients with systemic lupus erythematosus.

CTLA-4 is a critical gatekeeper of T-cell activation and immunological tolerance and has been implicated in patients with a variety of autoimmune diseases through genetic association. Since T cells from patients with the autoimmune disease systemic lupus erythematosus (SLE) display a characteristic hyperactive phenotype, we investigated the function of CTLA-4 in SLE. Our results reveal increased CTLA-4 expression in FOXP3(-) responder T cells from patients with SLE compared with other autoimmune rheumatic diseases and healthy controls. However, CTLA-4 was unable to regulate T-cell proliferation, lipid microdomain formation and phosphorylation of TCR-zeta following CD3/CD28 co-stimulation, in contrast to healthy T cells. Although lupus T cells responded in vitro to CD3/CD28 co-stimulation, there was no parallel increase in CTLA-4 expression, which would normally provide a break on T-cell proliferation. These defects were associated with exclusion of CTLA-4 from lipid microdomains providing an anatomical basis for its loss of function. Collectively our data identify CTLA-4 dysfunction as a potential cause for abnormal T-cell activation in patients with SLE, which could be targeted for therapy.

Development of a Structured Query Language and Natural Language Processing Algorithm to Identify Lung Nodules in a Cancer Centre.

Importance: The stratification of indeterminate lung nodules is a growing problem, but the burden of lung nodules on healthcare services is not well-described. Manual service evaluation and research cohort curation can be time-consuming and potentially improved by automation. Objective: To automate lung nodule identification in a tertiary cancer centre. Methods: This retrospective cohort study used Electronic Healthcare Records to identify CT reports generated between 31st October 2011 and 24th July 2020. A structured query language/natural language processing tool was developed to classify reports according to lung nodule status. Performance was externally validated. Sentences were used to train machine-learning classifiers to predict concerning nodule features in 2,000 patients. Results: 14,586 patients with lung nodules were identified. The cancer types most commonly associated with lung nodules were lung (39%), neuro-endocrine (38%), skin (35%), colorectal (33%) and sarcoma (33%). Lung nodule patients had a greater proportion of metastatic diagnoses (45 vs. 23%, p < 0.001), a higher mean post-baseline scan number (6.56 vs. 1.93, p < 0.001), and a shorter mean scan interval (4.1 vs. 5.9 months, p < 0.001) than those without nodules. Inter-observer agreement for sentence classification was 0.94 internally and 0.98 externally. Sensitivity and specificity for nodule identification were 93 and 99% internally, and 100 and 100% at external validation, respectively. A linear-support vector machine model predicted concerning sentence features with 94% accuracy. Conclusion: We have developed and validated an accurate tool for automated lung nodule identification that is valuable for service evaluation and research data acquisition.

Immune Checkpoint Inhibitor and Radiotherapy-Related Pneumonitis: An Informatics Approach to Determine Real-World Incidence, Severity, Management, and Resource Implications.

Pneumonitis is a well-described, potentially life-threatening adverse effect of immune checkpoint inhibitors (ICI) and thoracic radiotherapy. It can require additional investigations, treatment, and interruption of cancer therapy. It is important for clinicians to have an awareness of its incidence and severity, however real-world data are lacking and do not always correlate with findings from clinical trials. Similarly, there is a dearth of information on cost impact of symptomatic pneumonitis. Informatics approaches are increasingly being applied to healthcare data for their ability to identify specific patient cohorts efficiently, at scale. We developed a Structured Query Language (SQL)-based informatics algorithm which we applied to CT report text to identify cases of ICI and radiotherapy pneumonitis between 1/1/2015 and 31/12/2020. Further data on severity, investigations, medical management were also acquired from the electronic health record. We identified 248 cases of pneumonitis attributable to ICI and/or radiotherapy, of which 139 were symptomatic with CTCAE severity grade 2 or more. The grade ≥2 ICI pneumonitis incidence in our cohort is 5.43%, greater than the all-grade 1.3-2.7% incidence reported in the literature. Time to onset of ICI pneumonitis was also longer in our cohort (mean 4.5 months, range 4 days-21 months), compared to the median 2.7 months (range 9 days-19.2 months) described in the literature. The estimated average healthcare cost of symptomatic pneumonitis is £3932.33 per patient. In this study we use an informatics approach to present new real-world data on the incidence, severity, management, and resource burden of ICI and radiotherapy pneumonitis. To our knowledge, this is the first study to look at real-world incidence and healthcare resource utilisation at the per-patient level in a UK cancer hospital. Improved management of pneumonitis may facilitate prompt continuation of cancer therapy, and improved outcomes for this not insubstantial cohort of patients.

Interventional Pulmonology: A Brave New World.

Interventional pulmonology is a dynamic and evolving field in respiratory medicine. Advances have improved the ability to diagnose and manage diseases of the airways. A shift toward early detection of malignant disease has generated a focus on innovative diagnostic techniques. With patient populations living longer with malignant and benign diseases, the role for interventional bronchoscopy has grown. In cancer groups, novel immunotherapies have improved the prospects of clinical outcomes and reignited a focus on optimizing patient performance status to enable access to anticancer therapy. This review discusses current and emerging diagnostic modalities and therapeutic approaches available to manage airway diseases.

Peer victimisation and internalising difficulties: The moderating role of friendship quality.

A cross-sectional study is reported in which loneliness and emotional problems are explored in adolescent victims of direct or relational bullying, together with the potentially moderating influence of friendship quality. Adolescents (N=401, mean age 13.5) completed the School Relationships Questionnaire, to identify bullying and victimisation roles, the Friendship Activity Questionnaire (FAQ), the Strengths and Difficulties Questionnaire (SDQ) to assess emotional problems, and the Loneliness and Social Dissatisfaction Questionnaire (LSDQ). Relational victims, but not direct victims reported significantly elevated feelings of loneliness and emotional problems compared to non-victims. Direct victims reported a significantly higher quality of friendship, compared to non-victims. Poor quality of friendship was also associated with high levels of loneliness, and vice versa for direct victims, but not for relational victims. This indicates that the higher quality of friendship found in direct victims is associated with the reduced levels of loneliness found in this group. Given the cross-sectional nature of this study, it is not possible to ascertain whether this association truly reflects the role of friendship quality as a moderator, and hence protective factor against adverse influences of victimisation. The different mechanisms underlying direct and relational victimisation are important for future research and intervention programmes.

Localised normocalcaemic tetany secondary to dehydration in an individual with Gitelman syndrome.

Dehydration is a common presentation to any emergency department with symptoms ranging from lethargy, confusion, oliguria as well as those specific to the underlying cause. In this case we describe a young patient who following a short history of vomiting and abdominal pain developed carpopedal spasm and distal parasthesia on a background of Gitelman syndrome. Biochemical blood analysis showed a marked hypokalaemia, hypomagnesaemia and mild metabolic alkalosis in addition to a prolonged QTc interval of 592 ms seen on ECG. Following fluid replacement and electrolyte correction his clinical symptoms resolved along with QTc normalisation. This case demonstrates a patient with a rare and interesting renal disorder who presented with typical biochemical and ECG abnormalities in addition to tetany in the presence of normal plasma calcium.