Neutrophil-Derived Peptidyl Arginine Deiminase Activity Contributes to Pulmonary Emphysema by Enhancing Elastin Degradation.

In chronic obstructive pulmonary disease (COPD), inflammation gives rise to protease-mediated degradation of the key extracellular matrix protein, elastin, which causes irreversible loss of pulmonary function. Intervention against proteolysis has met with limited success in COPD, due in part to our incomplete understanding of the mechanisms that underlie disease pathogenesis. Peptidyl arginine deiminase (PAD) enzymes are a known modifier of proteolytic susceptibility, but their involvement in COPD in the lungs of affected individuals is underexplored. In this study, we showed that enzyme isotypes PAD2 and PAD4 are present in primary granules of neutrophils and that cells from people with COPD release increased levels of PADs when compared with neutrophils of healthy control subjects. By examining bronchoalveolar lavage and lung tissue samples of patients with COPD or matched smoking and nonsmoking counterparts with normal lung function, we reveal that COPD presents with markedly increased airway concentrations of PADs. Ex vivo, we established citrullinated elastin in the peripheral airways of people with COPD, and in vitro, elastin citrullination significantly enhanced its proteolytic degradation by serine and matrix metalloproteinases, including neutrophil elastase and matrix metalloprotease-12, respectively. These results provide a mechanism by which neutrophil-released PADs affect lung function decline, indicating promise for the future development of PAD-based therapeutics for preserving lung function in patients with COPD.

The effect of cartilage dehydration and rehydration on quantitative ultrashort echo time biomarkers.

Background: The effect of dehydration of ex vivo cartilage samples and rehydration with native synovial fluid or normal saline on quantitative ultrashort echo time (UTE) biomarkers are unknown. We aimed to investigate the effect of cartilage dehydration-rehydration on UTE biomarkers and to compare the rehydration capabilities of native synovial fluid and normal saline. Methods: A total of 37 cartilage samples were harvested from patients (n=5) who underwent total knee replacement. Fresh cartilage samples were exposed to air to dehydrate for 2 hours after baseline magnetic resonance (MR) scanning, then randomly divided into two groups: one soaking in native synovial fluid (n=17) and the other in normal saline (n=20) to rehydrate for 4 hours. UTE-based biomarkers [T1, adiabatic T1r (AdiabT1r), macromolecular fraction (MMF), magnetization transfer ratio (MTR), and T2*] and sample weights were evaluated for fresh, dehydrated, and rehydrated cartilage samples. Differences and agreements between groups were assessed using the values of fresh cartilage samples as reference standard. Results: Dehydrating in air for 2 hours resulted in significant weight loss (P=0.000). T1, AdiabT1r, and T2* decreased significantly while MMF and MTR increased significantly (all P<0.02). Non-significant differences were observed in cartilage weights after rehydrating in both synovial fluid and normal saline, with P values being 0.204 and 0.769, respectively. There were no significant differences in T1, AdiabT1r, MMF, and MTR after rehydrating in synovial fluid (P>0.0167, with Bonferroni correction) while T2* (P=0.001) still had significant differences compared with fresh samples. However, no significant differences were detected for any of the evaluated UTE biomarkers after rehydrating in normal saline (all P>0.05). No differences were detected in the agreement of UTE biomarker measurements between fresh samples and samples rehydrated with synovial fluid and normal saline. Conclusions: Cartilage dehydration resulted in significant changes in UTE biomarkers. Rehydrating with synovial fluid or normal saline had non-significant effect on all the evaluated UTE biomarkers except T2* values, which still had significant differences compared with fresh samples after rehydrating with synovial fluid. No significant difference was observed in the rehydration capabilities of native synovial fluid and normal saline.

Effect of elexacaftor/tezacaftor/ivacaftor on airway and systemic inflammation in cystic fibrosis.

Treatment with elexacaftor/tezacaftor/ivacaftor (ETI) has been shown to improve lung function in people with cystic fibrosis (PWCF). However, its biological effects remain incompletely understood. Here we describe alterations in pulmonary and systemic inflammation in PWCF following initiation of ETI. To address this, we collected spontaneously expectorated sputum and matching plasma from PWCF (n=30) immediately prior to ETI therapy, then again at 3 and 12 months. Within 3 months, PWCF demonstrated reduced activity of neutrophil elastase, proteinase three and cathepsin G, and decreased concentrations of interleukin (IL)-1ß and IL-8 in sputum, accompanied by decreased Pseudomonas burden and restoration of secretory leukoprotease inhibitor levels. Once treated with ETI, all airway inflammatory markers studied in PWCF had reduced to levels found in matched non-CF bronchiectasis controls. In PWCF with advanced disease, ETI resulted in decreased plasma concentrations of IL-6, C-reactive protein and soluble TNF receptor one as well as normalisation of levels of the acute phase protein, alpha-1 antitrypsin. These data clarify the immunomodulatory effects of ETI and underscore its role as a disease modifier.

Risk of persistent air leaks following percutaneous cryoablation and microwave ablation of peripheral lung tumors.

OBJECTIVES: To compare the incidence of persistent air leak (PAL) following cryoablation vs MWA of lung tumors when the ablation zone includes the pleura. METHODS: This bi-institutional retrospective cohort study evaluated consecutive peripheral lung tumors treated with cryoablation or MWA from 2006 to 2021. PAL was defined as an air leak for more than 24 h after chest tube placement or an enlarging postprocedural pneumothorax requiring chest tube placement. The pleural area included by the ablation zone was quantified on CT using semi-automated segmentation. PAL incidence was compared between ablation modalities and a parsimonious multivariable model was developed to assess the odds of PAL using generalized estimating equations and purposeful selection of predefined covariates. Time-to-local tumor progression (LTP) was compared between ablation modalities using Fine-Gray models, with death as a competing risk. RESULTS: In total, 260 tumors (mean diameter, 13.1 mm ± 7.4; mean distance to pleura, 3.6 mm ± 5.2) in 116 patients (mean age, 61.1 years ± 15.3; 60 women) and 173 sessions (112 cryoablations, 61 MWA) were included. PAL occurred after 25/173 (15%) sessions. The incidence was significantly lower following cryoablation compared to MWA (10 [9%] vs 15 [25%]; p = .006). The odds of PAL adjusted for the number of treated tumors per session were 67% lower following cryoablation (odds ratio = 0.33 [95% CI, 0.14-0.82]; p = .02) vs MWA. There was no significant difference in time-to-LTP between ablation modalities (p = .36). CONCLUSIONS: Cryoablation of peripheral lung tumors bears a lower risk of PAL compared to MWA when the ablation zone includes the pleura, without adversely affecting time-to-LTP. KEY POINTS: • The incidence of persistent air leaks after percutaneous ablation of peripheral lung tumors was lower following cryoablation compared to microwave ablation (9% vs 25%; p = .006). • The mean chest tube dwell time was 54% shorter following cryoablation compared to MWA (p = .04). • Local tumor progression did not differ between lung tumors treated with percutaneous cryoablation compared to microwave ablation (p = .36).

Safety and Effectiveness of Percutaneous Image-Guided Thermal Ablation of Juxtacardiac Lung Tumors.

PURPOSE: To evaluate the safety and effectiveness of percutaneous image-guided thermal ablation (IGTA) for juxtacardiac lung tumors. MATERIALS AND METHODS: This bi-institutional retrospective cohort study included 23 consecutive patients (13 [57%] male; mean age, 55 years ± 18) with 30 juxtacardiac lung tumors located ≤10 mm from the pericardium treated in 28 IGTA sessions (25 sessions of cryoablation and 3 sessions of microwave ablation) between April 2008 and August 2022. The primary outcome was any adverse cardiac event within 90 days after ablation. Secondary outcomes included noncardiac adverse events, local tumor progression-free survival (LT-PFS), and the cumulative incidence of local tumor progression with death as a competing risk. Two tumors treated without curative intent or follow-up imaging were considered in the safety analysis but not in the progression analysis. RESULTS: The median imaging follow-up duration was 22 months (interquartile range [IQR], 10-53 months). Primary technical success was achieved in 25 (89%) ablations. No adverse cardiac events attributable to IGTA occurred. One patient experienced a phrenic nerve injury. The median LT-PFS duration was 59 months (IQR, 32-73 months). At 1, 3, and 5 years, LT-PFS was 90% (95% CI, 78%-100%), 74% (CI, 53%-100%), and 45% (CI, 20%-97%), respectively, and the cumulative incidence of local tumor progression was 4.3% (CI, 0.29%-19%), 11% (CI, 1.6%-30%), and 26% (CI, 3.3%-58%), respectively. CONCLUSIONS: IGTA is safe and effective for lung tumors located ≤10 mm from the pericardium. No adverse cardiac events were not observed within 90 days after ablation.

Diagnosis and Treatment of Lung Cancer in the Setting of Interstitial Lung Disease.

Interstitial lung disease (ILD) including idiopathic pulmonary fibrosis increases the risk of developing lung cancer. Diagnosing and staging lung cancer in patients with ILD is challenging and requires careful interpretation of computed tomography (CT) and fluorodeoxyglucose PET/CT to distinguish nodules from areas of fibrosis. Minimally invasive tissue sampling is preferred but may be technically challenging given tumor location, coexistent fibrosis, and pneumothorax risk. Current treatment options include surgery, radiation therapy, percutaneous thermal ablation, and systemic therapy; however, ILD increases the risks associated with each treatment option, especially acute ILD exacerbation.

Dose immunogenicity study of a plant-produced influenza virus-like particle vaccine in layer hens.

Avian influenza poses one of the largest known threats to global poultry production and human health, but effective poultry vaccines can reduce infections rates, production losses and prevent mortalities, and reduce viral shed to limit further disease spread. The antigenic match between a vaccine and the circulating field influenza A viruses (IAV) is a critical determinant of vaccine efficacy. Here, an Agrobacterium tumefaciens-mediated transient tobacco plant (Nicotiana benthamiana) system was used to rapidly update an H6 influenza subtype virus-like particle (VLP) vaccine expressing the hemagglutininn (HA) protein of South African H6N2 IAVs circulating in 2020. Specific pathogen free White Leghorn layer hens vaccinated twice with ≥125 hemagglutinating unit (HAU) doses elicited protective antibody responses associated with prevention of viral shedding, i.e. hemaglutination inhibition (HI) mean geometric titres (GMTs) of ≥7 log2, for at least four months before dropping to approximately 5-6 log2 for at least another two months. A single vaccination with a 250 HAU dose induced significantly higher HI GMTs compared lower or higher doses, and was thus the optimal dose for chickens. Use of an adjuvant was essential, as the plant-produced H6 HA VLP alone did not induce protective antibody responses. Plant-produced IAV VLPs enable differentiation between vaccinated and infected animals (DIVA principle), and with sucrose density gradient-purified yields of 20,000 doses per kg of plant material, this highly efficacious, safe and economical technology holds enormous potential for improving poultry health in lower and middle-income countries.

Transperineal ultrasound-guided prostate biopsy: what the radiologist needs to know.

Transperineal ultrasound-guided (TP) prostate biopsy has been shown to significantly decrease the risk of post-procedural sepsis when compared to transrectal ultrasound-guided (TRUS) prostate biopsy. With guidance from the European Urology Association favouring adoption of a TP biopsy route, it is clear that, despite being a more technically challenging procedure, TP biopsy in an outpatient setting will replace TRUS biopsy. This paper gives the reader a succinct summary of outpatient transperineal prostate biopsy under local anaesthetic utilising a free-hand ultrasound technique. Patient preparation and consent process is outlined. A comprehensive pictorial review of the procedure, pitfalls and common post-procedural outcomes is presented. This paper provides a framework and guide for those wishing to adopt the transperineal approach under local anaesthetic.

Magnetic Resonance Imaging for Guidance and Follow-up of Thoracic Needle Biopsies and Thermal Ablations.

Magnetic resonance imaging (MRI) is used for the guidance and follow-up of percutaneous minimally invasive interventions in many body parts. In the thorax, computed tomography (CT) is currently the most used imaging modality for the guidance and follow-up of needle biopsies and thermal ablations. Compared with CT, MRI provides excellent soft tissue contrast, lacks ionizing radiation, and allows functional imaging. The role of MRI is limited in the thorax due to the low hydrogen proton density and many air-tissue interfaces of the lung, as well as respiratory and cardiac motion. Here, we review the current experience of MR-guided thoracic needle biopsies and of MR-guided thermal ablations targeting lesions in the lung, mediastinum, and the chest wall. We provide an overview of MR-compatible biopsy needles and ablation devices. We detail relevant MRI sequences and their relative advantages and disadvantages for procedural guidance, assessment of complications, and long-term follow-up. We compare the advantages and disadvantages of CT and MR for thoracic interventions and identify areas in need of improvement and additional research.

Update on Image-Guided Thermal Lung Ablation: Society Guidelines, Therapeutic Alternatives, and Postablation Imaging Findings.

Percutaneous image-guided thermal ablation (IGTA) has been endorsed by multiple societies as a safe and effective lung-preserving treatment of primary lung cancer and metastases involving the lung and chest wall. This article reviews the role of IGTA in the care continuum of patients with thoracic neoplasms and discusses strategies to identify the optimal local therapy considering patient and tumor characteristics. The advantages and disadvantages of percutaneous thermal ablation compared with surgical resection and stereotactic body radiotherapy are summarized. Principles of radiofrequency ablation, microwave ablation, and cryoablation, as well as the emerging use of transbronchial thermal ablation, are described. Specific considerations are presented regarding the role of thermal ablation for early-stage non-small cell lung cancer (NSCLC), multifocal primary NSCLC, pulmonary metastases, salvage of recurrent NSCLC after surgery or radiation, and pain palliation for tumors involving the chest wall. Recent changes to professional society guidelines regarding the role of thermal ablation in the lung, including for treatment of oligometastatic disease, are highlighted. Finally, recommendations are provided for imaging follow-up after thermal ablation of lung tumors, accompanied by examples of expected postoperative findings and patterns of disease recurrence.

A randomized, double-blind, placebo-controlled trial of intravenous alpha-1 antitrypsin for ARDS secondary to COVID-19.

Background: Patients with severe coronavirus disease 2019 (COVID-19) develop a febrile pro-inflammatory cytokinemia with accelerated progression to acute respiratory distress syndrome (ARDS). Here we report the results of a phase 2, multicenter, randomized, double-blind, placebo-controlled trial of intravenous (IV) plasma-purified alpha-1 antitrypsin (AAT) for moderate to severe ARDS secondary to COVID-19 (EudraCT 2020-001391-15). Methods: Patients (n = 36) were randomized to receive weekly placebo, weekly AAT (Prolastin, Grifols, S.A.; 120 mg/kg), or AAT once followed by weekly placebo. The primary endpoint was the change in plasma interleukin (IL)-6 concentration at 1 week. In addition to assessing safety and tolerability, changes in plasma levels of IL-1ß, IL-8, IL-10, and soluble tumor necrosis factor receptor 1 (sTNFR1) and clinical outcomes were assessed as secondary endpoints. Findings: Treatment with IV AAT resulted in decreased inflammation and was safe and well tolerated. The study met its primary endpoint, with decreased circulating IL-6 concentrations at 1 week in the treatment group. This was in contrast to the placebo group, where IL-6 was increased. Similarly, plasma sTNFR1 was substantially decreased in the treatment group while remaining unchanged in patients receiving placebo. IV AAT did not definitively reduce levels of IL-1ß, IL-8, and IL-10. No difference in mortality or ventilator-free days was observed between groups, although a trend toward decreased time on ventilator was observed in AAT-treated patients. Conclusions: In patients with COVID-19 and moderate to severe ARDS, treatment with IV AAT was safe, feasible, and biochemically efficacious. The data support progression to a phase 3 trial and prompt further investigation of AAT as an anti-inflammatory therapeutic. Funding: ECSA-2020-009; Elaine Galwey Research Bursary.

The bowel and beyond: extracolonic findings from CT colonography.

CT colonography has emerged as the investigation of choice for suspected colorectal cancer in patients when a colonoscopy in incomplete, is deemed high risk or is declined because of patient preference. Unlike a traditional colonoscopy, it frequently reveals extracolonic as well as colonic findings. Our study aimed to determine the prevalence, characteristics and potential significance of extracolonic findings on CT colonography within our own institution. A retrospective review was performed of 502 patients who underwent CT colonography in our institution between January 1, 2010 and January 4, 2015. Of 502 patients, 60.63% had at least one extracolonic finding. This was close to other similar-sized studies (Kumar et al. Radiology 236(2):519-526, 2005). However, our rate of E4 findings was significantly higher than that reported in larger studies at 5.3%(Pooler et al. AJR 206:313-318, 2016). The difference may be explained by our combination of symptomatic/screening patients or by the age and gender distribution of our population. Our study lends support to the hypothesis that CT colonography may be particularly useful in identifying clinically significant extracolonic findings in symptomatic patients. CT colonography may allow early identification of extracolonic malignancies and life-threatening conditions such as an abdominal aortic aneurysm at a preclinical stage when they are amenable to medical or surgical intervention. However, extracolonic findings may also result in unnecessary investigations for subsequently benign findings.

The potency of selatogrel, a reversible antagonist of the P2Y12 receptor, is affected by calcium concentration.

Here, we report the in vitro characterization of the P2Y12 receptor antagonist selatogrel (ACT-246475). Binding studies with radiolabeled selatogrel demonstrated that selatogrel is a competitive antagonist of ADP binding to the P2Y12 receptor with a fast onset of action. Consequently, selatogrel was confirmed to be a potent inhibitor of P2Y12-mediated intra-platelet signaling and ADP-induced platelet activation. Characterization of selatogrel in platelet-rich plasma in vitro demonstrated that the mode of anti-coagulation affected the anti-platelet potency. Specifically, in platelet-rich plasma containing physiological calcium concentration (anticoagulated with a direct thrombin inhibitor), selatogrel achieved half-maximal inhibition of ADP-induced platelet aggregation at a 3-fold lower concentration than in conditions with low calcium concentration (anticoagulated with citrate). Furthermore, calcium-dependent reduction in selatogrel potency was observed in whole blood platelet aggregation using the VerifyNow™ system with a 3.7-fold potency loss in low calcium conditions. A comparable potency loss was also observed with the reversible P2Y12 receptor antagonists ticagrelor, cangrelor and elinogrel. Furthermore, receptor-binding experiments using radiolabeled selatogrel confirmed a 3-fold lowering of selatogrel binding affinity to the P2Y12 receptor in low calcium conditions. In conclusion, our data suggest that in low calcium conditions (i.e., citrate-anticoagulated blood), there is a risk of underestimating the potency of reversible P2Y12 receptor antagonists. To avoid overdosing, and a potential increase in bleeding risk, we propose that the ex vivo evaluation of reversible P2Y12 receptor antagonists should be performed with platelet assay systems containing physiological calcium concentration.

Comparison of Percutaneous Image-Guided Microwave Ablation and Cryoablation for Sarcoma Lung Metastases: A 10-Year Experience.

BACKGROUND. To our knowledge, outcomes between percutaneous microwave ablation (MWA) and cryoablation of sarcoma lung metastases have not been compared. OBJECTIVE. The purpose of this study was to compare technical success, complications, local tumor control, and overall survival (OS) after MWA versus cryoablation of sarcoma lung metastases. METHODS. This retrospective cohort study included 27 patients (16 women, 11 men; median age, 64 years; Eastern Cooperative Oncology Group performance score, 0-2) who, from 2009 to 2021, underwent 39 percutaneous CT-guided ablation sessions (21 MWA and 18 cryoablation sessions; one to four sessions per patient) to treat 65 sarcoma lung metastases (median number of tumors per patient, one [range, one to 12]; median tumor diameter, 11.0 mm [range, 5-33 mm]; 25% of tumors were nonperipheral). We compared complications according to ablation modality by use of generalized estimating equations. We evaluated ablation modality, tumor size, and location (peripheral vs nonperipheral) in relation to local tumor progression by use of proportional Cox hazard models, with death as the competing risk. We estimated OS using the Kaplan-Meier method. RESULTS. Primary technical success was 97% for both modalities. Median follow-up was 23 months (range, one to 102 months; interquartile range, 12-44 months). A total of seven of 61 tumors (11%) showed local progression. Estimated 1-year and 2-year local control rates were, for tumors 1 cm or smaller, 97% and 95% after MWA versus 99% and 98% after cryoablation, and for tumors larger than 1 cm, 74% and 62% after MWA versus 86% and 79% after cryoablation. Tumor size of 1 cm or smaller was associated with a decreased cumulative incidence of local progression (p = .048); ablation modality and tumor location were not associated with progression (p = .86 and p = .54, respectively). Complications (Common Terminology Criteria for Adverse Events [CTCAE] grade, ≤ 3) occurred in 17 of 39 sessions (44%), prompting chest tube placement in nine (23%). There were no CTCAE grade 4 or 5 complications. OS at 1, 2, and 3 years was 100%, 89%, and 82%, respectively. CONCLUSION. High primary technical success, local control, and OS support the use of MWA and cryoablation for treating sarcoma lung metastases. Ablation modality and tumor location did not affect local progression. The rate of local tumor progression was low, especially for small tumors. No life-threatening complications occurred. CLINICAL IMPACT. Percutaneous MWA and cryoablation are both suited for the treatment of sarcoma lung metastases, especially for tumors 1 cm or smaller, whether peripheral or nonperipheral. Complications, if they occur, are not life-threatening.

In vitro and in vivo modulation of NADPH oxidase activity and reactive oxygen species production in human neutrophils by α1-antitrypsin.

Oxidative stress from innate immune cells is a driving mechanism that underlies COPD pathogenesis. Individuals with α-1 antitrypsin (AAT) deficiency (AATD) have a dramatically increased risk of developing COPD. To understand this further, the aim of this study was to investigate whether AATD presents with altered neutrophil NADPH oxidase activation, due to the specific lack of plasma AAT. Experiments were performed using circulating neutrophils isolated from healthy controls and individuals with AATD. Superoxide anion (O2 -) production was determined from the rate of reduction of cytochrome c. Quantification of membrane NADPH oxidase subunits was performed by mass spectrometry and Western blot analysis. The clinical significance of our in vitro findings was assessed in patients with AATD and severe COPD receiving intravenous AAT replacement therapy. In vitro, AAT significantly inhibited O2 - production by stimulated neutrophils and suppressed receptor stimulation of cyclic adenosine monophosphate and extracellular signal-regulated kinase (ERK)1/2 phosphorylation. In addition, AAT reduced plasma membrane translocation of cytosolic phox components of the NADPH oxidase. Ex vivo, AATD neutrophils demonstrated increased plasma membrane-associated p67phox and p47phox and significantly increased O2 - production. The described variance in phox protein membrane assembly was resolved post-AAT augmentation therapy in vivo, the effects of which significantly reduced AATD neutrophil O2 - production to that of healthy control cells. These results expand our knowledge on the mechanism of neutrophil-driven airways disease associated with AATD. Therapeutic AAT augmentation modified neutrophil NADPH oxidase assembly and reactive oxygen species production, with implications for clinical use in conditions in which oxidative stress plays a pathogenic role.

Integrated atomic force microscopy and x-ray irradiation for in situ characterization of radiation-induced processes.

Understanding radiation-induced chemical and physical transformations at material interfaces is important across diverse fields, but experimental approaches are often limited to either ex situ observations or in situ electron microscopy or synchrotron-based methods, in which cases the radiation type and dose are inextricably tied to the imaging basis itself. In this work, we overcome this limitation by demonstrating integration of an x-ray source with an atomic force microscope to directly monitor radiolytically driven interfacial chemistry at the nanoscale. We illustrate the value of in situ observations by examining effects of radiolysis on material adhesion forces in aqueous solution as well as examining the production of alkali nitrates at the interface between an alkali halide crystal surface and air. For the examined salt-air interface, direct visualization under flexible experimental conditions greatly extends prior observations by enabling the transformation process to be followed comprehensively from source-to-sink with mass balance quantitation. Our novel rad-atomic force microscope opens doors into understanding the dynamics of radiolytically driven mass transfer and surface alteration at the nanoscale in real-time.