Unfolded Von Willebrand Factor Binds Protein S and Reduces Anticoagulant Activity.

Protein S (PS), the critical plasma cofactor for the anticoagulants tissue factor (TF) pathway inhibitor (TFPI) and activated protein C (APC), circulates in two functionally distinct pools: free (anticoagulant) or bound to complement component 4b-binding protein (C4BP) (anti-inflammatory). Acquired free PS deficiency is detected in several viral infections, but its cause is unclear. Here, we identified a shear-dependent interaction between PS and von Willebrand Factor (VWF) by mass spectrometry. Consistently, plasma PS and VWF comigrated in both native and agarose gel electrophoresis. The PS/VWF interaction was blocked by TFPI but not APC, suggesting an interaction with the C-terminal sex hormone binding globulin (SHBG) region of PS. Microfluidic systems, mimicking arterial laminar flow or disrupted turbulent flow, demonstrated that PS stably binds VWF as VWF unfolds under turbulent flow. PS/VWF complexes also localized to platelet thrombi under laminar arterial flow. In thrombin generation-based assays, shearing plasma decreased PS activity, an effect not seen in the absence of VWF. Finally, free PS deficiency in COVID-19 patients, measured using an antibody that binds near the C4BP binding site in SHBG, correlated with changes in VWF, but not C4BP, and with thrombin generation. Our data suggest that PS binds to a shear-exposed site on VWF, thus sequestering free PS and decreasing its anticoagulant activity, which would account for the increased thrombin generation potential. As many viral infections present with free PS deficiency, elevated circulating VWF, and increased vascular shear, we propose that the PS/VWF interaction reported here is a likely contributor to virus-associated thrombotic risk.

Deep learning, 3D ultrastructural analysis reveals quantitative differences in platelet and organelle packing in COVID-19/SARSCoV2 patient-derived platelets.

Platelets contribute to COVID-19 clinical manifestations, of which microclotting in the pulmonary vasculature has been a prominent symptom. To investigate the potential diagnostic contributions of overall platelet morphology and their α-granules and mitochondria to the understanding of platelet hyperactivation and micro-clotting, we undertook a 3D ultrastructural approach. Because differences might be small, we used the high-contrast, high-resolution technique of focused ion beam scanning EM (FIB-SEM) and employed deep learning computational methods to evaluate nearly 600 individual platelets and 30 000 included organelles within three healthy controls and three severely ill COVID-19 patients. Statistical analysis reveals that the α-granule/mitochondrion-to-plateletvolume ratio is significantly greater in COVID-19 patient platelets indicating a denser packing of organelles, and a more compact platelet. The COVID-19 patient platelets were significantly smaller -by 35% in volume - with most of the difference in organelle packing density being due to decreased platelet size. There was little to no 3D ultrastructural evidence for differential activation of the platelets from COVID-19 patients. Though limited by sample size, our studies suggest that factors outside of the platelets themselves are likely responsible for COVID-19 complications. Our studies show how deep learning 3D methodology can become the gold standard for 3D ultrastructural studies of platelets.

COVID-19 patients exhibit a range of symptoms including microclotting. Clotting is a complex process involving both circulating proteins and platelets, a cell within the blood. Increased clotting is suggestive of an increased level of platelet activation. If this were true, we reasoned that parts of the platelet involved in the release of platelet contents during clotting would have lost their content and appear as expanded, empty "ghosts." To test this, we drew blood from severely ill COVID-19 patients and compared the platelets within the blood draws to those from healthy volunteers. All procedures were done under careful attention to biosafety and approved by health authorities. We looked within the platelets for empty ghosts by the high magnification technique of electron microscopy. To count the ghosts, we developed new computer software. In the end, we found little difference between the COVID patient platelets and the healthy donor platelets. The results suggest that circulating proteins outside of the platelet are more important to the strong clotting response. The software developed will be used to analyze other disease states.

Assessing the effects of therapeutic combinations on SARS-CoV-2 infected patient outcomes: A big data approach.

BACKGROUND: The COVID-19 pandemic has demonstrated the need for efficient and comprehensive, simultaneous assessment of multiple combined novel therapies for viral infection across the range of illness severity. Randomized Controlled Trials (RCT) are the gold standard by which efficacy of therapeutic agents is demonstrated. However, they rarely are designed to assess treatment combinations across all relevant subgroups. A big data approach to analyzing real-world impacts of therapies may confirm or supplement RCT evidence to further assess effectiveness of therapeutic options for rapidly evolving diseases such as COVID-19. METHODS: Gradient Boosted Decision Tree, Deep and Convolutional Neural Network classifiers were implemented and trained on the National COVID Cohort Collaborative (N3C) data repository to predict the patients' outcome of death or discharge. Models leveraged the patients' characteristics, the severity of COVID-19 at diagnosis, and the calculated proportion of days on different treatment combinations after diagnosis as features to predict the outcome. Then, the most accurate model is utilized by eXplainable Artificial Intelligence (XAI) algorithms to provide insights about the learned treatment combination impacts on the model's final outcome prediction. RESULTS: Gradient Boosted Decision Tree classifiers present the highest prediction accuracy in identifying patient outcomes with area under the receiver operator characteristic curve of 0.90 and accuracy of 0.81 for the outcomes of death or sufficient improvement to be discharged. The resulting model predicts the treatment combinations of anticoagulants and steroids are associated with the highest probability of improvement, followed by combined anticoagulants and targeted antivirals. In contrast, monotherapies of single drugs, including use of anticoagulants without steroid or antivirals are associated with poorer outcomes. CONCLUSIONS: This machine learning model by accurately predicting the mortality provides insights about the treatment combinations associated with clinical improvement in COVID-19 patients. Analysis of the model's components suggests benefit to treatment with combination of steroids, antivirals, and anticoagulant medication. The approach also provides a framework for simultaneously evaluating multiple real-world therapeutic combinations in future research studies.

Extranodal Extension Improves AJCC-8 Accuracy in HPV+ Oropharyngeal Cancer in a High-Risk Population.

OBJECTIVES: The American Joint Committee on Cancer's 8th edition (AJCC-8) separates oropharyngeal squamous cell carcinomas (OPSCCs) into human papillomavirus-positive (HPV+) tumors and HPV-negative tumors. Although AJCC-8 improves prognostic prediction for survival for the majority of HPV+ OPSCC, outliers are still encountered. The goal of this manuscript is to validate the AJCC-8 as a better metric of survivability than the AJCC-7 in an historically under-served rural population with confounding variables, such as tobacco use, alcohol consumption, and poor health care access and to analyze the role of extranodal extension (ENE) in this population. DESIGN: Retrospective cohort study. RESULTS: Compared to AJCC-7, AJCC-8 had a higher odds ratio (OR) for predicting mortality of stage IV HPV+ OPSCCs versus stages I-III. On multivariate analysis, HPV+ OPSCCs with ENE had a higher OR of mortality compared to ENE- OPSCCs. In addition, HPV+ OPSCC patients with a Charlson Comorbidity Index (CCI) > 3 had a higher OR of mortality compared to those with a CCI ≤ 3. Patients with Medicaid/self-pay status had a higher OR of mortality compared to those with private insurance/Medicare. Finally, patients from rural populations had a higher OR of presenting with stage IV disease, a CCI > 3, and Medicaid/self-pay status. CONCLUSIONS: Despite not being a discrete part of the AJCC-8 staging rubric, ENE was found to have a significant impact on mortality among this population, whereas tobacco use had no effect. Rural patients were more likely to present with stage IV disease, CCI > 3, and Medicaid/self-pay status. Stage IV disease was also associated with a higher OR of mortality. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:2621-2626, 2023.

Risk Factors Associated with Complications in Rhinoplasty Using Polydioxanone Plates.

OBJECTIVE: Polydioxanone (PDS) plates are utilized in septorhinoplasty to reconstruct the nasal septum. Our goal was to analyze factors affecting short- and long-term complications in patients undergoing septorhinoplasty using PDS plates with a particular focus on smoking and diabetes. METHODS: This is a retrospective review of patients undergoing septorhinoplasty with PDS plates analyzing risk factors and outcomes. Early complications included infection, hematoma, extrusion, and septal thickening. Late complications included septal perforation, obstruction, revision, and infection. Complication rate was assessed as a function of demographics, diabetes, smoking, autoimmune disease, cancer, and trauma. Multivariate analyses assessed the contributions of these variables, and Chi-square analyses specifically addressed smoking and diabetes. RESULTS: A total of 119 patients were included. In multivariate analysis, current smoking had a large negative effect on late outcomes (OR 2.00, 95% CI 0.59-6.55), while diabetes did not show any significant difference. Targeted Chi-squared analysis showed a statistically significant effect of current smoking on increased early complications (OR 3.65, 95% CI 1.67-7.63) and a large but not statistically significant increase in long-term complications (OR 4.20, 95% CI 0.72-22.74). In both models, diabetes was not shown to have an effect on early or late complications. CONCLUSION: Current smokers undergoing septorhinoplasty with a PDS plate showed a statistically significant association with early complications and large but not statistically significant association with late complications. Diabetic patients were not found to have an increased complication risk. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Assessing the Applicability of the TALK Score: A Modification for Concurrent Tobacco Use During Treatment.

OBJECTIVE: The previously described TALK score (T-stage, Albumin, Liquor, Karnofsky Performance Status) has been proposed as a method to predict laryngectomy-free survival (LFS) in patients undergoing definitive chemoradiation (CRT). This study assesses its use as well as a modification to include continued tobacco use. STUDY DESIGN: Retrospective chart review. SETTING: Academic institution from 2004 to 2020. METHODS: Patients diagnosed with larynx or hypopharynx cancer undergoing CRT were reviewed. Clinically relevant variables were collected (TALK), which were dichotomized per previously set cutoffs. Concurrent tobacco use was evaluated and also dichotomized as 0 or 1. Multivariate analysis was conducted to determine which factors were most predictive of the key outcomes of survival and LFS. RESULTS: A total of 2514 patient charts were evaluated. Patients treated for larynx cancer with primary CRT with complete data were included, ultimately totaling 300. Of these, 78 patients required salvage total laryngectomy (TL). Multivariate analysis demonstrated that LFS was best predicted by tobacco use during treatment (odds ratio [OR] 0.3465, 95% confidence interval [CI] 0.1862-0.6300) and Karnofsky Performance Status (OR 0.1646, 95% CI 0.0673-0.3662). Tobacco use during treatment was also strongly predictive of survival. Excluding T4 tumors, the utilization of tobacco in place of T-stage improved the accuracy of the predictive model in this cohort. CONCLUSION: Given that a T-stage of 4 is typically treated with total laryngectomy, modification of the TALK score to include tobacco use during treatment (tALK) for patients with T < 4 can be used to improve prediction of 3-year LFS and overall survival.

HIV, Tuberculosis, and Otogenic Intracranial Sepsis: A Devastating Disease With a Subtle Presentation.

OBJECTIVES: To undertake a large-scale review of otogenic intracranial sepsis in an area of highly prevalent HIV and tuberculosis (TB) to re-examine and inform early diagnosis and treatment efforts. METHODS: Seventy-seven consecutive cases of otogenic intracranial sepsis in KwaZulu-Natal, South Africa were reviewed for demographics, presentation, imaging, HIV status, culture results, and outcomes. RESULTS: The most common intracranial complications were intracranial abscess (46.8%), hydrocephalus (31.2%), subdural empyema (28.6%), and epidural empyema (26.0%). Ear discharge (87.0%), postauricular abscess (29.9%), and hearing loss (29.9%) were notable presenting symptoms. Overall mortality was 15.6%. Of the 45.5% of patients with HIV testing, 54.2% were HIV+, Mortality among HIV+ patients was 15.8% but only 6.3% in HIV- patients (p = 0.61, OR = 2.8). Eight patients (10.4%) had culture or histological evidence of TB infection. CONCLUSIONS: Otogenic intracranial complications continue to present late and are associated with significant mortality and morbidity, despite advances in diagnostic and treatment modalities. This study represents one of the largest case-series in the literature, and the first to specifically evaluate the effects of HIV and TB infection.Patient presentation and severity of illness varied; however, a majority of patients presented with ear discharge and no focal neurological signs. An effect size for higher mortality among HIV+ patients compared with HIV- patients was noted but was not significant. Tuberculosis infection was prevalent compared with previous studies.This study reinforces the need for enhanced screening and early treatment of ear disease to minimize associated mortality and morbidity, particularly in immunocompromised patients.

Lung Tissue Resident Memory T-Cells in the Immune Response to Mycobacterium tuberculosis.

Despite widespread BCG vaccination and effective anti-TB drugs, Tuberculosis (TB) remains the leading cause of death from an infectious agent worldwide. Several recent publications give reasons to be optimistic about the possibility of a more effective vaccine, but the only full-scale clinical trial conducted failed to show protection above BCG. The immunogenicity of vaccines in humans is primarily evaluated by the systemic immune responses they generate, despite the fact that a correlation between these responses and protection from TB disease has not been demonstrated. A novel approach to tackling this problem is to study the local immune responses that occur at the site of TB infection in the human lung, rather than those detectable in blood. There is a growing understanding that pathogen specific T-cell immunity can be highly localized at the site of infection, due to the existence of tissue resident memory T-cells (Trm). Notably, these cells do not recirculate in the blood and thus may not be represented in studies of the systemic immune response. Here, we review the potential role of Trms as a component of the TB immune response and discuss how a better understanding of this response could be harnessed to improve TB vaccine efficacy.

Type 3 ILCs in Lung Disease.

The lungs represent a complex immune setting, balancing external environmental signals with a poised immune response that must protect from infection, mediate tissue repair, and maintain lung function. Innate lymphoid cells (ILCs) play a central role in tissue repair and homeostasis, and mediate protective immunity in a variety of mucosal tissues, including the lung. All three ILC subsets are present in the airways of both mice and humans; and ILC2s shown to have pivotal roles in asthma, airway hyper-responsiveness, and parasitic worm infection. The involvement of ILC3s in respiratory diseases is less well-defined, but they are known to be critical in homeostasis, infection and inflammation at other mucosal barriers, such as the gut. Moreover, they are important players in the IL17/IL22 axis, which is key to lung health. In this review, we discuss the emerging role of ILC3s in the context of infectious and inflammatory lung diseases, with a focus on data from human subjects.

Percutaneous Implantation of an Entirely Intracardiac Leadless Pacemaker.

BACKGROUND: Cardiac pacemakers are limited by device-related complications, notably infection and problems related to pacemaker leads. We studied a miniaturized, fully self-contained leadless pacemaker that is nonsurgically implanted in the right ventricle with the use of a catheter. METHODS: In this multicenter study, we implanted an active-fixation leadless cardiac pacemaker in patients who required permanent single-chamber ventricular pacing. The primary efficacy end point was both an acceptable pacing threshold (≤2.0 V at 0.4 msec) and an acceptable sensing amplitude (R wave ≥5.0 mV, or a value equal to or greater than the value at implantation) through 6 months. The primary safety end point was freedom from device-related serious adverse events through 6 months. In this ongoing study, the prespecified analysis of the primary end points was performed on data from the first 300 patients who completed 6 months of follow-up (primary cohort). The rates of the efficacy end point and safety end point were compared with performance goals (based on historical data) of 85% and 86%, respectively. Additional outcomes were assessed in all 526 patients who were enrolled as of June 2015 (the total cohort). RESULTS: The leadless pacemaker was successfully implanted in 504 of the 526 patients in the total cohort (95.8%). The intention-to-treat primary efficacy end point was met in 270 of the 300 patients in the primary cohort (90.0%; 95% confidence interval [CI], 86.0 to 93.2, P=0.007), and the primary safety end point was met in 280 of the 300 patients (93.3%; 95% CI, 89.9 to 95.9; P<0.001). At 6 months, device-related serious adverse events were observed in 6.7% of the patients; events included device dislodgement with percutaneous retrieval (in 1.7%), cardiac perforation (in 1.3%), and pacing-threshold elevation requiring percutaneous retrieval and device replacement (in 1.3%). CONCLUSIONS: The leadless cardiac pacemaker met prespecified pacing and sensing requirements in the large majority of patients. Device-related serious adverse events occurred in approximately 1 in 15 patients. (Funded by St. Jude Medical; LEADLESS II ClinicalTrials.gov number, NCT02030418.).

IgG4-related disease of the aortic valve: a report of two cases and review of the literature.

IgG4-related disease (IgG4-RD) is a relatively recently described disorder that can affect multiple organ systems, including the cardiovascular system. While most reported cases of cardiovascular involvement are of the aorta, usually the abdominal aorta, rare isolated reports of involvement of the heart proper have been described. Herein, we describe two cases of IgG4-RD involving the aortic valve. Each case was found to be associated with increased levels of IgG4 in the tissue and one case resulted in the subsequent discovery of IgG4-related pancreatitis.

Analysis of different device-based intrathoracic impedance vectors for detection of heart failure events (from the Detect Fluid Early from Intrathoracic Impedance Monitoring study).

Detect Fluid Early from Intrathoracic Impedance Monitoring (DEFEAT-PE) is a prospective, multicenter study of multiple intrathoracic impedance vectors to detect pulmonary congestion (PC) events. Changes in intrathoracic impedance between the right ventricular (RV) coil and device can (RVcoil→Can) of implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy ICDs (CRT-Ds) are used clinically for the detection of PC events, but other impedance vectors and algorithms have not been studied prospectively. An initial 75-patient study was used to derive optimal impedance vectors to detect PC events, with 2 vector combinations selected for prospective analysis in DEFEAT-PE (ICD vectors: RVring→Can + RVcoil→Can, detection threshold 13 days; CRT-D vectors: left ventricular ring→Can + RVcoil→Can, detection threshold 14 days). Impedance changes were considered true positive if detected <30 days before an adjudicated PC event. One hundred sixty-two patients were enrolled (80 with ICDs and 82 with CRT-Ds), all with ≥1 previous PC event. One hundred forty-four patients provided study data, with 214 patient-years of follow-up and 139 PC events. Sensitivity for PC events of the prespecified algorithms was as follows: ICD: sensitivity 32.3%, false-positive rate 1.28 per patient-year; CRT-D: sensitivity 32.4%, false-positive rate 1.66 per patient-year. An alternative algorithm, ultimately approved by the US Food and Drug Administration (RVring→Can + RVcoil→Can, detection threshold 14 days), resulted in (for all patients) sensitivity of 21.6% and a false-positive rate of 0.9 per patient-year. The CRT-D thoracic impedance vector algorithm selected in the derivation study was not superior to the ICD algorithm RVring→Can + RVcoil→Can when studied prospectively. In conclusion, to achieve an acceptably low false-positive rate, the intrathoracic impedance algorithms studied in DEFEAT-PE resulted in low sensitivity for the prediction of heart failure events.

Feasibility of using multivector impedance to monitor pulmonary congestion in heart failure patients.

PURPOSE: Pulmonary edema (PE) is associated with fluid accumulation in the lungs. Device-based impedance measurements have been used to detect fluid overload prior to hospitalization. However, studies have reported a high false positive rate (FPR). The objective of this study was to develop and test a new multivector impedance-based algorithm that reliably tracks PE clinical events. METHODS: We enrolled patients with implanted CRT-Ds in 23 US centers within 2 weeks of device implant. Six-vector impedance data was collected automatically by the CRT-Ds every 30 min during emergency department visits/hospitalizations and every 2 h at all other times. Detection algorithms for cardiac resynchronization therapy defibrillator (CRT-D) and implantable cardiac defibrillator (ICD) devices were developed using those impedance vectors that would be available in corresponding devices and retrospectively evaluated. RESULTS: There were 75 patients (69 % male), mean age 66 ± 12 years, with a LVEF of 23 ± 6 % and QRS of 149 ± 25 ms. Twenty-one major clinical events occurred over 8.2 ± 2.6 months of follow-up time. CRT-D vector combinations resulted in a sensitivity of 71.4 % (95 % confidence interval 47.8-88.7) and a FPR of 0.56 (0.30-0.94) false positives per patient-year (FPs/pt-yr); ICD vector combinations resulted in a sensitivity of 61.9 % (38.4-81.9) and a FPR of 0.63 (0.36-0.90) FPs/pt-yr. In comparison, the single-vector RVCoil-Can implementation of this algorithm resulted in a sensitivity of 57.1 % (34.0-78.2) and a FPR of 0.74 (0.44-1.12) FPs/pt-yr. CONCLUSIONS: This multivector impedance algorithm was effective in tracking PE clinical events in this patient population. Additional studies are needed to prospectively evaluate the performance of this algorithm in a larger population.

Clinical performance of the St. Jude Medical Riata defibrillation lead in a large patient population.

OBJECTIVE: The purpose of this large multicenter study was to evaluate the long-term reliability of an implantable cardioverter defibrillator (ICD) lead to determine the incidence of adverse events (AEs). BACKGROUND: A recent concern has been the performance of cardiac defibrillator leads. There have been conflicting reports regarding the rate of lead perforation and other AEs. METHODS: Medical records from patients implanted from 6-1-2001 to 11-27-2007 with the St. Jude Medical Riata family of RV leads at 23 US (N = 12,969) and 5 German (N = 2,418) centers were reviewed for chronic lead-related AEs. These included perforation, dislodgment, conductor fracture and insulation damage. The mean follow-up period was 18.0 months. AEs were defined as those that required Riata lead revision, extraction, or replacement. RESULTS: The incidence of lead AEs was <1% for each AE type. Perforation occurred in 0.38%, dislodgement in 0.93%, conductor fracture in 0.18%, and insulation damage in 0.21% of patients studied. CONCLUSIONS: During the follow-up of the 15,387 patients with Riata leads, the incidence of AEs which included perforation, dislodgement, conductor fraction and insulation damage was low and within the range of what is considered clinically acceptable.

Acute evaluation of programmer-guided AV/PV and VV delay optimization comparing an IEGM method and echocardiogram for cardiac resynchronization therapy in heart failure patients and dual-chamber ICD implants.

INTRODUCTION: Intracardiac delay optimization of biventricular and dual-chamber pacing devices currently relies on time-consuming echocardiographic measurements. A novel intracardiac electrogram (IEGM) method for atrioventricular (AV/PV) and interventricular (VV) delay optimization was developed, which can be performed during routine device follow-up. METHODS AND RESULTS: In this prospective, nonrandomized, multi-center trial, patients previously implanted with St. Jude Medical cardiac resynchronization therapy defibrillator (CRT-D) devices or dual-chamber implantable cardioverter defibrillators (ICDs) underwent standard AV/PV and/or VV delay optimization guided by Doppler echocardiogram measurements of the maximum aortic velocity time integral (aortic VTI). Aortic VTI measurements applying the IEGM method recommended delays were then obtained in all patients. Fifty-eight patients (age: 68 +/- 11 years; 81% male; 74% ischemic) and 57 patients (age: 71 +/- 10 years; 74% male; 71% ischemic) were enrolled for AV/PV and VV delay evaluation, respectively. An independent core lab determined the maximum aortic VTIs. Data analysis of the AV, PV, and VV delays demonstrated the concordance correlation coefficient (CCC) between the standard method aortic VTI values and the IEGM method aortic VTI values was 97.5%, 96.1%, and 96.6%, respectively. All analyses demonstrated that the CCC > 90% (P < 0.05). CONCLUSION: The automated programmer-based IEGM method provides a reliable and simpler alternative to standard techniques for the optimization of AV/PV and VV delay settings in patients with CRT-D devices and dual-chamber ICDs.

The Visible Cement Data Set.

With advances in x-ray microtomography, it is now possible to obtain three-dimensional representations of a material's microstructure with a voxel size of less than one micrometer. The Visible Cement Data Set represents a collection of 3-D data sets obtained using the European Synchrotron Radiation Facility in Grenoble, France in September 2000. Most of the images obtained are for hydrating portland cement pastes, with a few data sets representing hydrating Plaster of Paris and a common building brick. All of these data sets are being made available on the Visible Cement Data Set website at http://visiblecement.nist.gov. The website includes the raw 3-D datafiles, a description of the material imaged for each data set, example two-dimensional images and visualizations for each data set, and a collection of C language computer programs that will be of use in processing and analyzing the 3-D microstructural images. This paper provides the details of the experiments performed at the ESRF, the analysis procedures utilized in obtaining the data set files, and a few representative example images for each of the three materials investigated.