Machine Learning Models for Predicting Zirconocene Properties and Barriers.

Zr metallocenes have significant potential to be highly tunable polyethylene catalysts through modification of the aromatic ligand framework. Here we report the development of multiple machine learning models using a large library (>700 systems) of DFT-calculated zirconocene properties and barriers for ethylene polymerization. We show that very accurate machine learning models are possible for HOMO-LUMO gaps of precatalysts but the performance significantly depends on the machine learning algorithm and type of featurization, such as fingerprints, Coulomb matrices, smooth overlap of atomic positions, or persistence images.

ReaLigands: A Ligand Library Cultivated from Experiment and Intended for Molecular Computational Catalyst Design.

Computational catalyst design requires identification of a metal and ligand that together result in the desired reaction reactivity and/or selectivity. A major impediment to translating computational designs to experiments is evaluating ligands that are likely to be synthesized. Here, we provide a solution to this impediment with our ReaLigands library that contains >30,000 monodentate, bidentate (didentate), tridentate, and larger ligands cultivated by dismantling experimentally reported crystal structures.

Development of a Definition of Postacute Sequelae of SARS-CoV-2 Infection.

Importance: SARS-CoV-2 infection is associated with persistent, relapsing, or new symptoms or other health effects occurring after acute infection, termed postacute sequelae of SARS-CoV-2 infection (PASC), also known as long COVID. Characterizing PASC requires analysis of prospectively and uniformly collected data from diverse uninfected and infected individuals.

Objective: To develop a definition of PASC using self-reported symptoms and describe PASC frequencies across cohorts, vaccination status, and number of infections.

High-fidelity detection, subtyping, and localization of five skin neoplasms using supervised and semi-supervised learning.

Background: Skin cancers are the most common malignancies diagnosed worldwide. While the early detection and treatment of pre-cancerous and cancerous skin lesions can dramatically improve outcomes, factors such as a global shortage of pathologists, increased workloads, and high rates of diagnostic discordance underscore the need for techniques that improve pathology workflows. Although AI models are now being used to classify lesions from whole slide images (WSIs), diagnostic performance rarely surpasses that of expert pathologists.

A pragmatic randomized trial of home-based testing for COVID-19 in rural Native American and Latino communities: Protocol for the "Protecting our Communities" study.

Background: Home-based testing for COVID-19 has potential to reduce existing health care disparities among underserved populations in the United States. However, implementation of home-based tests in these communities may face significant barriers. This study evaluates the acceptability, feasibility, and success of home-based testing and the potential added benefit of active support from trusted community health workers for Native Americans and Hispanic/Latino adults living in rural Montana and Washington states.

Efficacy of interferon beta-1a plus remdesivir compared with remdesivir alone in hospitalised adults with COVID-19: a double-bind, randomised, placebo-controlled, phase 3 trial.

Background: Functional impairment of interferon, a natural antiviral component of the immune system, is associated with the pathogenesis and severity of COVID-19. We aimed to compare the efficacy of interferon beta-1a in combination with remdesivir compared with remdesivir alone in hospitalised patients with COVID-19.

Methods: We did a double-blind, randomised, placebo-controlled trial at 63 hospitals across five countries (Japan, Mexico, Singapore, South Korea, and the USA).

Respiratory Impacts of Wildland Fire Smoke: Future Challenges and Policy Opportunities. An Official American Thoracic Society Workshop Report.

Wildland fires are diminishing air quality on a seasonal and regional basis, raising concerns about respiratory health risks to the public and occupational groups. This American Thoracic Society (ATS) workshop was convened in 2019 to meet the growing health threat of wildland fire smoke. The workshop brought together a multidisciplinary group of 19 experts, including wildland fire managers, public health officials, epidemiologists, toxicologists, and pediatric and adult pulmonologists.

Factors influencing decline in quality of life in smokers without airflow obstruction: The COPDGene study.

Introduction: Current and former smokers with normal spirometry and with Preserved Ratio Impaired Spirometry (PRISm) experience respiratory events similar to chronic obstructive pulmonary disease (COPD) exacerbations. Exacerbations significantly reduce quality of life (QoL) in COPD patients however the effect of respiratory exacerbations on QoL in these groups is unknown. We hypothesized that exacerbations and change in exacerbation status would predict QoL decline among normal spirometry and PRISm participants in COPDGene.

Metoprolol for the Prevention of Acute Exacerbations of COPD.

Background: Observational studies suggest that beta-blockers may reduce the risk of exacerbations and death in patients with moderate or severe chronic obstructive pulmonary disease (COPD), but these findings have not been confirmed in randomized trials.

Methods: In this prospective, randomized trial, we assigned patients between the ages of 40 and 85 years who had COPD to receive either a beta-blocker (extended-release metoprolol) or placebo. All the patients had a clinical history of COPD, along with moderate airflow limitation and an increased risk of exacerbations, as evidenced by a history of exacerbations during the previous year or the prescribed use of supplemental oxygen.

Plasma cathelicidin and longitudinal lung function in current and former smokers.

Introduction: Cathelicidin (also known as LL-37 in humans) is an antimicrobial peptide secreted by epithelial and immune cells and regulated by vitamin D. The immunological roles of cathelicidin make it a putative biomarker to identify individuals at risk for reduced lung function. The objective of this study is to determine potential independent associations between low plasma cathelicidin and longitudinal lung function in current or former smokers without COPD.

Anemia and Adverse Outcomes in a Chronic Obstructive Pulmonary Disease Population with a High Burden of Comorbidities. An Analysis from SPIROMICS.

Rationale: Chronic obstructive pulmonary disease (COPD) is a common cause of morbidity and associated with a significant burden of comorbidities. Although anemia is associated with adverse outcomes in COPD, its contribution to outcomes in individuals with other comorbid chronic diseases is not well understood.

Objectives: This study examines the association of anemia with outcomes in a large, well-characterized COPD cohort, and attempts to understand the contribution of anemia to outcomes and phenotypes in individuals with other comorbidities.

Respiratory symptoms in smokers with normal spirometry: clinical significance and management considerations.

Purpose Of Review: Current respiratory society guidelines recommend confirming the diagnosis of chronic obstructive pulmonary disease (COPD) with demonstration of airflow obstruction on spirometry. However, multiple recent studies have demonstrated that smokers without overt airflow obstruction on spirometry, termed symptomatic smokers, have evidence of structural lung disease on imaging, have a substantial symptom burden, and also suffer respiratory exacerbations. In this review, we provide an overview of the epidemiology of symptomatic smokers, and address issues of screening and diagnosis, evaluation, and management considerations.

Lower serum IgA is associated with COPD exacerbation risk in SPIROMICS.

Background: Decreased but measurable serum IgA levels (≤70 mg/dL) have been associated with risk for infections in some populations, but are unstudied in COPD. This study tested the hypothesis that subnormal serum IgA levels would be associated with exacerbation risk in COPD.

Methods: Data were analyzed from 1,049 COPD participants from the observational cohort study SPIROMICS (535 (51%) women; mean age 66.

Rural Residence and Chronic Obstructive Pulmonary Disease Exacerbations. Analysis of the SPIROMICS Cohort.

Rural residence is associated with poor outcomes in several chronic diseases. The association between rural residence and chronic obstructive pulmonary disease (COPD) exacerbations remains unclear. In this work, we sought to determine the independent association between rural residence and COPD-related outcomes, including COPD exacerbations, airflow obstruction, and symptom burden.

HIV Infection Is Independently Associated with Increased CT Scan Lung Density.

Rationale And Objectives: Noninfectious pulmonary complications are common among HIV-infected individuals and may be detected early by quantitative computed tomography (CT) scanning. The association of HIV disease markers with CT lung density measurement remains poorly understood.

Materials And Methods: One hundred twenty-five participants free of spirometry-defined lung disease were recruited from a longitudinal cohort study of HIV-infected and HIV-uninfected individuals to undergo standardized CT scan of the chest.

HIV Suppression Restores the Lung Mucosal CD4+ T-Cell Viral Immune Response and Resolves CD8+ T-Cell Alveolitis in Patients at Risk for HIV-Associated Chronic Obstructive Pulmonary Disease.

Background: Lung CD4 T-cell depletion and dysfunction, CD8 T-cell alveolitis, smoking, and poor control of human immunodeficiency virus (HIV) are features of HIV-associated chronic obstructive pulmonary disease (COPD), but these changes have not been evaluated in smokers at risk for COPD. We evaluated the impact of viral suppression following initiation of antiretroviral therapy (ART) on HIV-specific immunity and the balance of the CD4 T-cell to CD8 T-cell ratio in the lung.

Methods: Using flow cytometry, we assessed the T-cell immune response in lung and blood specimens obtained from 12 actively smoking HIV-positive patients before ART initiation and after ART-associated viral suppression.

Obesity Is Associated With Increased Morbidity in Moderate to Severe COPD.

Background: Obesity is prevalent in the United States; however, the impact of obesity on COPD morbidity is unclear. We hypothesized that obesity is associated with worse outcomes in COPD.

Methods: We examined 3,631 participants from the multicenter prospective cohort study Genetic Epidemiology of COPD (COPDGene) who had spirometry-confirmed COPD, a postbronchodilator FEV < 80% predicted, and a BMI ≥ 18.

Short Communication: HIV Controller T Cells Effectively Inhibit Viral Replication in Alveolar Macrophages.

Macrophages are targets of HIV-1 infection, and control of viral replication within these cells may be an important component of a T-cell-based vaccine. Although several studies have analyzed the ability of CD8 T cells to inhibit viral replication in monocyte-derived macrophages, the effect of T cells on HIV-1-infected tissue macrophages is less clear. We demonstrate here that both CD4 and CD8 T-cell effectors from HIV controllers are capable of suppressing viral replication in bronchoalveolar lavage-derived alveolar macrophages.

Implementation of a COPD Screening Questionnaire in an Outpatient HIV Clinic.

Human immunodeficiency virus (HIV) is associated with increased risk for chronic obstructive pulmonary disease (COPD); yet substantial under-recognition of COPD exists. We administered a patient-completed, physician-reviewed COPD screening tool in an outpatient HIV clinic to determine whether screening is feasible or possible. Patients attending nonacute, routine HIV care visits were provided a brief COPD screening tool, which included three questions focused on age, respiratory symptoms, and smoking history.

HIV Impairs Lung Epithelial Integrity and Enters the Epithelium to Promote Chronic Lung Inflammation.

Several clinical studies show that individuals with HIV are at an increased risk for worsened lung function and for the development of COPD, although the mechanism underlying this increased susceptibility is poorly understood. The airway epithelium, situated at the interface between the external environment and the lung parenchyma, acts as a physical and immunological barrier that secretes mucins and cytokines in response to noxious stimuli which can contribute to the pathobiology of chronic obstructive pulmonary disease (COPD). We sought to determine the effects of HIV on the lung epithelium.

COPD Overlap Syndromes: Asthma and Beyond.

This article serves as a CME-available, enduring material summary of the following COPD9presentations: "COPD and Asthma" Prescott Woodruff, MD, MPH "COPD and Lung Cancer" William Bulman, MD "COPD and Bronchiectasis" Jeremy Clain, MD "COPD and Interstitial Lung Disease" GeorgeWashko, MD.