Stiffening of the human proximal pulmonary artery with increasing age.

Adverse effects of large artery stiffening are well established in the systemic circulation; stiffening of the proximal pulmonary artery (PPA) and its sequelae are poorly understood. We combined in vivo (n = 6) with ex vivo data from cadavers (n = 8) and organ donors (n = 13), ages 18 to 89, to assess whether aging of the PPA associates with changes in distensibility, biaxial wall strain, wall thickness, vessel diameter, and wall composition. Aging exhibited significant negative associations with distensibility and cyclic biaxial strain of the PPA (p ≤ 0.

Remodeling of Murine Branch Pulmonary Arteries Under Chronic Hypoxia and Short-Term Normoxic Recovery.

Chronic hypoxia plays a central role in diverse pulmonary pathologies, but its effects on longitudinal changes in the biomechanical behavior of proximal pulmonary arteries remain poorly understood. Similarly, effects of normoxic recovery have not been well studied. Here, we report hypoxia-induced changes in composition, vasoactivity, and passive biaxial mechanics in the main branch pulmonary artery of male C57BL/6J mice exposed to 10% FiO2 for 1, 2, or 3 weeks.

Developmental changes in lung function of mice are independent of sex as a biological variable.

Pulmonary function testing (PFT) in mice includes biomechanical assessment of lung function relevant to physiology in health and its alteration in disease, hence, it is frequently used in preclinical modeling of human lung pathologies. Despite numerous reports of PFT in mice of various ages, there is a lack of reference data for developing mice collected using consistent methods. Therefore, we profiled PFTs in male and female C57BL/6J mice from 2 to 23 wk of age, providing reference values for age- and sex-dependent changes in mouse lung biomechanics during development and young adulthood.

The association between beta-natriuretic peptide (BNP) serum levels and liberation from mechanical ventilation.

Prolonged time on mechanical ventilation is associated with multiple consequences for both the patient and medical facility. Based on anecdotal evidence that sustained elevation of beta-natriuretic protein (BNP) during a patient's stay in a long-term acute care hospital (LTACH) was associated with failure to wean from prolonged mechanical ventilation, we investigated if there is an association between a decrease in BNP levels during one's stay and successful weaning from prolonged mechanical ventilation. We performed a retrospective study of 66 patient records revealing no correlation between lowering BNP levels and probability of liberating a patient from prolonged mechanical ventilation in an LTACH environment where the probability of liberation from mechanical ventilation is high (> 85%).

The Burden of COVID-19 Mortality Due to Referrals From Skilled Nursing Facilities in a Small Community Hospital.

Background: Amidst the COVID-19 pandemic, nursing home residents have seen a significant increase in hospitalizations. However, there is a lack of published data on the healthcare provided to these individuals in community hospitals. This knowledge gap hinders our understanding and evaluation of the quality and outcomes of care received by nursing home residents when they are hospitalized for COVID-19 or other medical conditions.

Prognostic variables and decannulation of tracheostomy in the long-term acute care environment: a case for clinician-driven decision-making.

Purpose: Tracheostomy is a necessary procedure required for prolonged mechanical ventilation in long-term acute care hospitals (LTACH). Many factors influence successful decannulation, or tracheostomy removal, and it is unclear what factors are essential for determining decannulation. The purpose of this study was to determine retrospective performance of single prognostic variables for successful decannulation, like peak expiratory flow measurement, overnight oximetry testing, and blood gas analysis.

A Multi-omic Analysis of the Human Lung Reveals Distinct Cell Specific Aging and Senescence Molecular Programs.

Age is a major risk factor for lung disease. To understand the mechanisms underlying this association, we characterized the changing cellular, genomic, transcriptional, and epigenetic landscape of lung aging using bulk and single-cell RNAseq (scRNAseq) data. Our analysis revealed age-associated gene networks that reflected hallmarks of aging, including mitochondrial dysfunction, inflammation, and cellular senescence.

VISTA (PD-1H) Is a Crucial Immune Regulator to Limit Pulmonary Fibrosis.

VISTA (V domain immunoglobulin suppressor of T cell activation, also called PD-1H [programmed death-1 homolog]), a novel immune regulator expressed on myeloid and T lymphocyte lineages, is upregulated in mouse and human idiopathic pulmonary fibrosis (IPF). However, the significance of VISTA and its therapeutic potential in regulating IPF has yet to be defined. To determine the role of VISTA and its therapeutic potential in IPF, the expression profile of VISTA was evaluated from human single-cell RNA sequencing data (IPF Cell Atlas).

Compromised Cardiopulmonary Function in Fibulin-5 Deficient Mice.

Competent elastic fibers are critical to the function of the lung and right circulation. Murine models of elastopathies can aid in understanding the functional roles of the elastin and elastin-associated glycoproteins that constitute elastic fibers. Here, we quantify together lung and pulmonary arterial structure, function, and mechanics with right heart function in a mouse model deficient in the elastin-associated glycoprotein fibulin-5.

Mechanisms of Hypoxia-Induced Pulmonary Arterial Stiffening in Mice Revealed by a Functional Genetics Assay of Structural, Functional, and Transcriptomic Data.

Hypoxia adversely affects the pulmonary circulation of mammals, including vasoconstriction leading to elevated pulmonary arterial pressures. The clinical importance of changes in the structure and function of the large, elastic pulmonary arteries is gaining increased attention, particularly regarding impact in multiple chronic cardiopulmonary conditions. We establish a multi-disciplinary workflow to understand better transcriptional, microstructural, and functional changes of the pulmonary artery in response to sustained hypoxia and how these changes inter-relate.

Integrated Single-Cell Atlas of Endothelial Cells of the Human Lung.

Background: Cellular diversity of the lung endothelium has not been systematically characterized in humans. We provide a reference atlas of human lung endothelial cells (ECs) to facilitate a better understanding of the phenotypic diversity and composition of cells comprising the lung endothelium.

Methods: We reprocessed human control single-cell RNA sequencing (scRNAseq) data from 6 datasets.

Disinfection of from N95 respirators with ozone: a pilot study.

Introduction: Personal protective equipment shortages require the reuse of N95 respirators. We sought the necessary conditions for ozone to disinfect N95 respirators for reuse and the effects of multiple cycles of exposure.

Methods: Portions of 3M 1870 N95 respirators were exposed to ozone at 400 ppm with 80% humidity for 2 hours to determine effectiveness of ozone on killing .

Plasma mitochondrial DNA is associated with extrapulmonary sarcoidosis.

Sarcoidosis is an unpredictable granulomatous disease in which African Americans disproportionately experience aggressive phenotypes. Mitochondrial DNA (mtDNA) released by cells in response to various stressors contributes to tissue remodelling and inflammation. While extracellular mtDNA has emerged as a biomarker in multiple diseases, its relevance to sarcoidosis remains unknown.

Pulmonary artery pseudoaneurysm causing massive hemoptysis in hyperimmunoglobulin E syndrome: a case report.

Background: Hyperimmunoglobulin E syndrome (HIES) is a rare primary immunodeficiency disorder defined by high serum immunoglobulin E titers that is associated with recurrent respiratory infections, formation of pneumoatoceles, recurrent skin abscesses, and characteristic dental and skeletal abnormalities.

Case Presentation: We report a case of a 56-year-old male with a history of HIES, cavitary mycetomas, and allergic bronchopulmonary aspergillosis who presented with recurrent massive hemoptysis. Bronchial artery angiography and bronchoscopy failed to identify active hemorrhage, and two embolizations of the bronchial artery did not resolve the bleeding.

Early and prolonged opportunities to practice suturing increases medical student comfort with suturing during clerkships: Suturing during cadaver dissection.

Medical students are expected to perform common procedures such as suturing on patients during their third-year clerkships. However, these experiences are often viewed by medical students as stressors rather than opportunities for learning. The source of this stress is the lack of instruction on common procedures prior to being asked to observe or perform the procedure on a patient.

Central Nervous System Oxygen Toxicity and Hyperbaric Oxygen Seizures.

Introduction: The use of hyperbaric oxygen (O2) as a therapeutic agent carries with it the risk of central nervous system (CNS) O2 toxicity.

Methods: To further the understanding of this risk and the nature of its molecular mechanism, a review was conducted on the literature from various fields.

Results: Numerous physiological changes are produced by increased partial pressures of oxygen (Po2), which may ultimately result in CNS O2 toxicity.

Brief neurocognitive screening in youth with brain tumours: A preliminary investigation of the Lebby-Asbell Neurocognitive Screening Examination (LANSE).

Primary Objective: It is well-documented that survivors of paediatric brain tumour are at risk for neurocognitive deficits resulting in an increased interest in neurocognitive assessment for these youth. Given the scarcity of well-validated brief assessments for this purpose, this study examines the reliability and validity of a brief neurocognitive screening measure.

Research Design: Cross-sectional data on youth (aged 6-17.

PhytobezoarInduced Small Bowel Obstruction in a Young Male with Virgin Abdomen.

Phytobezoars are a rare cause of small bowel obstruction. Such cases are most commonly associated with previous abdominal surgery or poor dentition or psychiatric conditions. A 40 year old man with a virgin abdomen and excellent dentition and no underlying psychiatric condition presented with an acute abdomen.

Molecular effects of familial hypertrophic cardiomyopathy-related mutations in the TNT1 domain of cTnT.

Familial hypertrophic cardiomyopathy (FHC) is one of the most common genetic causes of heart disease. Approximately 15% of FHC-related mutations are found in cTnT [cardiac troponin (cTn) T]. Most of the cTnT FHC-related mutations are in or flanking the N-tail TNT1 domain that directly interacts with overlapping tropomyosin (Tm).