Biological Effects of Corticosteroids on Pneumococcal Pneumonia in Mice and Humans (preprint)

Background: Streptococcus pneumoniae is the most common bacterial cause of community acquired pneumonia and the acute respiratory distress syndrome (ARDS). Some clinical trials have demonstrated a beneficial effect of corticosteroid therapy in community acquired pneumonia, COVID-19, and ARDS, but the mechanisms of this benefit remain unclear. The objective of this study was to investigate the effects of corticosteroids on the pulmonary biology of pneumococcal pneumonia in an observational cohort of mechanically ventilated patients and in a mouse model of bacterial pneumonia with Streptococcus pneumoniae. Methods: We studied gene expression with lower respiratory tract transcriptomes from a cohort of mechanically ventilated patients and in mice. We also carried out comprehensive physiologic, biochemical, and histological analyses in mice to identify the mechanisms of lung injury in Streptococcus pneumoniae with and without adjunctive steroid therapy. Results: Transcriptomic analysis identified pleiotropic effects of steroid therapy on the lower respiratory tract in critically ill patients with pneumococcal pneumonia, findings that were reproducible in mice. In mice with pneumonia, dexamethasone in combination with ceftriaxone reduced (1) pulmonary edema formation, (2) alveolar protein permeability, (3) proinflammatory cytokine release, (4) histopathologic lung injury score, and (5) hypoxemia but did not increase bacterial burden. Conclusions: The gene expression studies in patients and in the mice support the clinical relevance of the mouse studies, which replicate several features of pneumococcal pneumonia and steroid therapy in humans. In combination with appropriate antibiotic therapy in mice, treatment of pneumococcal pneumonia with steroid therapy reduced hypoxemia, pulmonary edema, lung permeability, and histologic criteria of lung injury, and also altered inflammatory responses at the protein and gene expression level. The results from these studies provide evidence for the mechanisms that may explain the beneficial effects of glucocorticoid therapy in patients with community acquired pneumonia from Streptococcus Pneumoniae.

Follow-Up In Patients With Respiratory Disability After ARDS Related To COVID-19: A Systematic Review (preprint)

Introduction: Acute Respiratory Distress Syndrome (ARDS) is an acute inflammatory pulmonary process that leads to protein-rich, non-hydrostatic pulmonary edema, undesirable hypoxemia, and lung stiffness. Due to COVID-19, a significant proportion of people who will require hospitalization to treat COVID-19, between 15%-30%, will develop severe respiratory failure, ARDS, and an increased likelihood of intubation for mechanical respiratory support. Aim: To investigate the pulmonary function in COVID-19-related ARDS survivors after hospitalization. Methods: A search was performed on the Greek and international literature, as well as at the online Databases PubMed, Cochrane, Embase, and Google Scholar. Exclusion and integration criteria were set for the studies found, and a flow chart was created for the studies included. Results: Through the search, 352 articles were found matching the subject under study, and after further evaluation, four articles were included. The majority of the articles highlight that after ARDS occurs due to COVID-19, patients face impaired pulmonary function in combination with other physical and psychological symptoms like weakness, anxiety, depression, and generalized functional disability. Conclusions: It is a fact that COVID-19 disease, in severe form and following the need for hospitalization due to the development of ARDS, results in an increased likelihood of prolonged occurrence of some symptoms of impaired respiratory function. Impaired CO2 diffusion is observed in the majority of studies as well as impaired respiratory function regarding prolonged imaging findings and impaired physical function. Keywords: ARDS, SARS-CoV-2, ICU, COVID-19, follow up, respiratory function

Efficacy and safety of intravenous imatinib in COVID-19 ARDS: a randomized, double-blind, placebo-controlled clinical trial.

PURPOSE: A hallmark of acute respiratory distress syndrome (ARDS) is hypoxaemic respiratory failure due to pulmonary vascular hyperpermeability. The tyrosine kinase inhibitor imatinib reversed pulmonary capillary leak in preclinical studies and improved clinical outcomes in hospitalized COVID-19 patients. We investigated the effect of intravenous (IV) imatinib on pulmonary edema in COVID-19 ARDS. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled trial. Invasively ventilated patients with moderate-to-severe COVID-19 ARDS were randomized to 200 mg IV imatinib or placebo twice daily for a maximum of seven days. The primary outcome was the change in extravascular lung water index (∆EVLWi) between days 1 and 4. Secondary outcomes included safety, duration of invasive ventilation, ventilator-free days (VFD) and 28-day mortality. Posthoc analyses were performed in previously identified biological subphenotypes. RESULTS: 66 patients were randomized to imatinib (n = 33) or placebo (n = 33). There was no difference in ∆EVLWi between the groups (0.19 ml/kg, 95% CI - 3.16 to 2.77, p = 0.89). Imatinib treatment did not affect duration of invasive ventilation (p = 0.29), VFD (p = 0.29) or 28-day mortality (p = 0.79). IV imatinib was well-tolerated and appeared safe. In a subgroup of patients characterized by high IL-6, TNFR1 and SP-D levels (n = 20), imatinib significantly decreased EVLWi per treatment day (- 1.17 ml/kg, 95% CI - 1.87 to - 0.44). CONCLUSIONS: IV imatinib did not reduce pulmonary edema or improve clinical outcomes in invasively ventilated COVID-19 patients. While this trial does not support the use of imatinib in the general COVID-19 ARDS population, imatinib reduced pulmonary edema in a subgroup of patients, underscoring the potential value of predictive enrichment in ARDS trials. Trial registration NCT04794088 , registered 11 March 2021. European Clinical Trials Database (EudraCT number: 2020-005447-23).

The diagnostic accuracy of lung ultrasound to determine PiCCO-derived extravascular lung water in invasively ventilated patients with COVID-19 ARDS (preprint)

Background: Lung ultrasound (LUS) is a non-invasive method to detect and quantify pulmonary edema. However, it remains uncertain how components of the LUS examination should be aggregated into a score for quantifying pulmonary edema. We examined the diagnostic accuracy of various LUS scores with the extravascular lung water index (EVLWi) assessed with PiCCO in patients with moderate-to-severe COVID-19 ARDS. Methods: In this predefined secondary analysis of a multicenter randomized-controlled trial (InventCOVID), patients were included within 48h after intubation and underwent LUS and EVLWi measurement at two time points (first and fourth study day). EVLWi and ∆EVLWi were used as reference standard. Two 12-region scores (global LUS and LUS-ARDS), an 8-region anterior-lateral score and a 4-region B-line score were used as index tests. Pearson correlation was performed and the area under the receiver operating characteristics curve (AUROCC) for severe pulmonary edema (EVLWi>15mL/kg) was calculated. Results: 26 of 30 patients (87%) had complete LUS and EVLWi measurements at time point 1 and 24 of 29 patients (83%) at time point 2. The global LUS (r=0.54), LUS-ARDS (r=0.58) and anterior-lateral score (r=0.54) were significantly correlated with EVLWi, while the B-line score was not (r=0.32). ∆global LUS (r=0.49) and ∆anterior-lateral LUS (r=0.52) were significantly correlated with ∆EVLWi, while correlation of ∆LUS-ARDS (r=0.43) and ∆B-lines (r=0.32) did not reach statistical significance. AUROCC for EVLWi>15ml/kg was 0.73 for the global LUS, 0.79 for the anterior-lateral and 0.85 for the LUS-ARDS score. Conclusions: The global LUS, LUS-ARDS and antero-lateral score can quantify PiCCO-derived pulmonary edema measurements in COVID-19 ARDS. The LUS-ARDS score showed the highest diagnostic accuracy for severe pulmonary edema. Trial registration: ClinicalTrials.gov identifier NCT04794088, registered on 11 March 2021. European Clinical Trials Database number 2020-005447-23.

Inter-rater reliability and prognostic value of baseline Radiographic Assessment of Lung Edema (RALE) scores in observational cohort studies of inpatients with COVID-19.

OBJECTIVES: To reliably quantify the radiographic severity of COVID-19 pneumonia with the Radiographic Assessment of Lung Edema (RALE) score on clinical chest X-rays among inpatients and examine the prognostic value of baseline RALE scores on COVID-19 clinical outcomes. SETTING: Hospitalised patients with COVID-19 in dedicated wards and intensive care units from two different hospital systems. PARTICIPANTS: 425 patients with COVID-19 in a discovery data set and 415 patients in a validation data set. PRIMARY AND SECONDARY OUTCOMES: We measured inter-rater reliability for RALE score annotations by different reviewers and examined for associations of consensus RALE scores with the level of respiratory support, demographics, physiologic variables, applied therapies, plasma host-response biomarkers, SARS-CoV-2 RNA load and clinical outcomes. RESULTS: Inter-rater agreement for RALE scores improved from fair to excellent following reviewer training and feedback (intraclass correlation coefficient of 0.85 vs 0.93, respectively). In the discovery cohort, the required level of respiratory support at the time of CXR acquisition (supplemental oxygen or non-invasive ventilation (n=178); invasive-mechanical ventilation (n=234), extracorporeal membrane oxygenation (n=13)) was significantly associated with RALE scores (median (IQR): 20.0 (14.1-26.7), 26.0 (20.5-34.0) and 44.5 (34.5-48.0), respectively, p<0.0001). Among invasively ventilated patients, RALE scores were significantly associated with worse respiratory mechanics (plateau and driving pressure) and gas exchange metrics (PaO2/FiO2 and ventilatory ratio), as well as higher plasma levels of IL-6, soluble receptor of advanced glycation end-products and soluble tumour necrosis factor receptor 1 (p<0.05). RALE scores were independently associated with 90-day survival in a multivariate Cox proportional hazards model (adjusted HR 1.04 (1.02-1.07), p=0.002). We replicated the significant associations of RALE scores with baseline disease severity and mortality in the independent validation data set. CONCLUSIONS: With a reproducible method to measure radiographic severity in COVID-19, we found significant associations with clinical and physiologic severity, host inflammation and clinical outcomes. The incorporation of radiographic severity assessments in clinical decision-making may provide important guidance for prognostication and treatment allocation in COVID-19.

Lung ultrasound-guided treatment for acute respiratory distress syndrome in a critically ill patient with severe COVID-19: a case report.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a very common disease in the intensive care unit (ICU), with rapid progression and high mortality. Infections caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can easily progress to ARDS in severely ill patients. Early and rapid diagnosis as well as screening for ARDS during treatment is very important. Owing to the particularity of patients with coronavirus disease 2019 (COVID-19), computed tomography (CT) examination is not always possible, and chest radiographs have a low sensitivity and specificity for the diagnosis of lung diseases. Therefore, bedside lung ultrasound (LUS) can be used as a new tool for the diagnosis of ARDS in patients with COVID-19. In the non-gravity-dependent pulmonary field, there are bilateral non-uniform B lines. In the dorsal pulmonary field, the B lines are denser and even appears as "white lung". Areas of consolidation are usually found in the dorsal pulmonary field, especially at the basilar part, with static or dynamic air bronchogram sign. In the fused B-line area, the "lung slip" usually decreases or disappears. The pleural line is irregular, thickened, and rough, with multiple small consolidations. The pulmonary ultrasound findings of primary and secondary ARDS were similar. CASE DESCRIPTION: In the abovementioned context, we share our experience with the treatment of one critical COVID-19 case and review the literature. An 81-year-old male patient with ARDS which is caused by COVID-19. The implementation of prone ventilation was guided by LUS, and we found that the pulmonary edema in the gravity-dependent area did improve over time. After 9 h of prone ventilation, the consolidation of the posterior area began to open. LUS shows the change from fragment sign to B line. After 16 h, the B-line was educed, indicating that pulmonary edema was improving. The oxygenation could be improved. Pulmonary ultrasound makes the monitoring of prone ventilation visualized. As the same time, the patient was accepted high-flow nasal oxygen, mechanical ventilation and treated with oseltamivir, lopinavir/ritonavir, abidol and cefoperazone-sulbactam. CONCLUSIONS: LUS-guided treatment was the key factor in the successful treatment of this case.

Severe Respiratory Failure Developing in the Course of High-Altitude Pulmonary Edema in an Alpinist with COVID-19 Pneumonia: A Case Report.

Pigon, Katarzyna, Ryszard Grzanka, Ewa Nowalany-Kozielska, and Andrzej Tomasik. Severe respiratory failure developing in the course of high-altitude pulmonary edema in an alpinist with COVID-19 pneumonia: a case report. High Alt Med Biol. 23:372-376, 2022.-The case of a 38-year-old Polish alpinist, evacuated from base camp (4,200 m) under Lenin's Peak due to severe high-altitude pulmonary edema (HAPE) and symptoms of acute mountain sickness/high-altitude cerebral edema (HACE), is presented. Starting the expedition, the man was asymptomatic and had a negative COVID-19 molecular test. After a few days of trekking, he developed typical HAPE and HACE. After evacuation to the hospital in Bishkek, a diagnosis of acute bronchopneumonia was made by computed tomography (CT) imaging. A COVID-19 test was not performed at that time. After returning to Poland, a complete noninvasive cardiac and pulmonary assessment disclosed no pathology. The initial chest CT reassessment was read as demonstrating the densities typical for COVID-19 pneumonia, and a SARS-CoV-2 antibody test corroborated the diagnosis. Pre-existing lung disease increases the risk of developing HAPE. In the era of the COVID-19 pandemic, people traveling at a high altitude and unaware of the infection are at particular risk.

Alpha-1 antitrypsin protects against phosgene-induced acute lung injury by activating the ID1-dependent anti-inflammatory response (preprint)

Phosgene, a highly dangerous chemical warfare agent, is widely used as an industrial chemical. Phosgene inhalation causes acute lung injury (ALI), which may further progress into pulmonary edema. Currently, there is no known antidote for phosgene poisoning. Alpha-1 antitrypsin (α1-AT) is a protease inhibitor that has been used to treat emphysema patients, who are deficient in α1-AT, for decades. Recent studies have shown that α1-AT has both anti-inflammatory and anti-SARS-CoV-2 effects. In this study, we aimed to investigate the role of α1-AT in phosgene-induced ALI. We observed a time-dependent increase in α1-AT expression and secretion in the lungs of rats exposed to phosgene. Interestingly, α1-AT was derived from neutrophils, but not from macrophages or alveolar type II cells, and α1-AT knockdown aggravated phosgene- and lipopolysaccharide (LPS)-induced inflammation and cell death in human bronchial epithelial cells (BEAS-2B). Conversely, α1-AT administration suppressed the inflammatory response and prevented death in LPS- and phosgene-exposed BEAS-2B cells. Furthermore, α1-AT treatment increased the expression of the inhibitor of DNA binding (ID1) gene, which suppressed NF-κB pathway activation, reduced inflammation, and inhibited cell death. These data demonstrate that neutrophil-derived α1-AT protects against phosgene-induced ALI by activating the ID1-dependent anti-inflammatory response. This study may provide novel strategies for the treatment of patients with phosgene-induced ALI.

Protein nanoparticle-induced osmotic pressure gradients modify pulmonary edema through hyperpermeability in acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS), caused by noncardiogenic pulmonary edema (PE), contributes significantly to Coronavirus 2019 (COVID-19)-associated morbidity and mortality. We explored the effect of transmembrane osmotic pressure (OP) gradients in PE using a fluorescence resonance energy transfer-based Intermediate filament (IF) tension optical probe. Angiotensin-II- and bradykinin-induced increases in intracellular protein nanoparticle (PN)-OP were associated with inflammasome production and cytoskeletal depolymerization. Intracellular protein nanoparticle production also resulted in cytomembrane hyperpolarization and L-VGCC-induced calcium signals, which differed from diacylglycerol-induced calcium increment via TRPC6 activation. Both pathways involve voltage-dependent cation influx and OP upregulation via SUR1-TRPM4 channels. Meanwhile, intra/extracellular PN-induced OP gradients across membranes upregulated pulmonary endothelial and alveolar barrier permeability. Attenuation of intracellular PN, calcium signals, and cation influx by drug combinations effectively relieved intracellular OP and pulmonary endothelial nonselective permeability, and improved epithelial fluid absorption and PE. Thus, PN-OP is pivotal in pulmonary edema in ARDS and COVID-19, and transmembrane OP recovery could be used to treat pulmonary edema and develop new drug targets in pulmonary injury.

Negative-pressure pulmonary edema after mammoplasty: a case report.

Negative-pressure pulmonary edema (NPPE) is a rare but life-threatening postoperative complication that occurs due to the acute obstruction of the upper airway. In our case report, we present a 25-year-old female patient who underwent elective mammoplasty under general anesthesia and developed NPPE 4 hours after extubation. The patient had a preoperative mallampati score of 3. After routine anesthesia induction, the patient was intubated with an endotracheal tube with a guide wire. Aspiration wasn't observed during extubation. The patient was followed in the post-anesthesia care unit (PACU) for 30 minutes with a saturation of 95% and was subsequently transferred to the service. Four hours after the operation, the patient was re-examined due to dyspnea and shortness of breath. Due to oxygen saturation of 88% and pO2of 56mmHg despite mask ventilation, the patient was admitted to the intensive care unit (ICU). A computed tomography (CT) scan revealed extensive diffuse ground-glass opacities and consolidations in both lungs. She did not respond to mask ventilation and was given non-invasive ventilation with continuous positive airway pressure (CPAP). Forced diuresis was induced with furosemide. Tachypnea resolved within 2 hours after CPAP was initiated, the patient did not require oxygen support and COVID-19 polymerase chain reaction (PCR) testing was negative. Subsequently, the patient was discharged to the clinical ward on postoperative day 1. When considering NPPE, early diagnosis and respiratory support are associated with reduced mortality and rapid recovery. Patients who develop laryngospasm during extubation must be closely monitored, and in the case of pulmonary edema, NPPE should be considered in the differential diagnosis.

Severe acute reentry high altitude pulmonary edema in pediatric patients: report of three cases and literature review.

BACKGROUND: High Altitude Pulmonary Edema (HAPE) is a fatal form of severe high-altitude illness. It is a form of noncardiogenic, noninfectious pulmonary edema secondary to alveolar hypoxia. The exact incidence of HAPE in children is unknown; however, most literature reports an incidence between 0.5-15%. There are three proposed HAPE types including classic HAPE, reentry HAPE, and high-altitude resident pulmonary edema (HARPE). CASE: We present three pediatric patients who were diagnosed with re-entry high altitude pulmonary edema and did not have any underlying cardiac abnormalities. All patients reside in areas of high altitude with a history of travelling to places of lower altitude. They had respiratory infections prior to the manifestation of HAPE. CONCLUSIONS: These are the first reported cases of children with reentry HAPE in Saudi Arabia. Reentry HAPE can occur in otherwise healthy children. Rapid ascent to high altitude and recent respiratory infections are the most commonly reported triggers. Prognosis is very favorable with a very rapid response to oxygen therapy. Education about HAPE is mandatory for families and health care workers working in high altitude areas.

Utility of a Pulmonary Oedema Score for Predicting the Need for Mechanical Ventilation in COVID-19 Patients in a General Hospital.

BACKGROUND: The Radiographic Assessment of Lung Edema (RALE) score has been used to estimate the extent of pulmonary damage in patients with acute respiratory distress syndrome and might be useful in patients with COVID-19. AIM OF THE STUDY: To examine factors associated with the need for mechanical ventilation in hospitalized patients with a clinical diagnosis of COVID-19, and to estimate the predictive value of the RALE score. METHODS: In a series of patients admitted between April 14 and August 28, 2020, with a clinical diagnosis of COVID-19, we assessed lung involvement on the chest radiograph using the RALE score. We examined factors associated with the need for mechanical ventilation in bivariate and multivariate analysis. The area under the receiver operating curve (AUC) indicated the predictive value of the RALE score for need for mechanical ventilation. RESULTS: Among 189 patients, 90 (48%) were judged to need mechanical ventilation, although only 60 were placed on a ventilator. The factors associated with the need for mechanical ventilation were a RALE score >6 points, age >50 years, and presence of chronic kidney disease. The AUC for the RALE score was 60.9% (95% CI 52.9-68.9), indicating it was an acceptable predictor of needing mechanical ventilation. CONCLUSIONS: A score for extent of pulmonary oedema on the plain chest radiograph was a useful predictor of the need for mechanical ventilation of hospitalized patients with COVID-19.

Chest Radiograph Severity and Its Association With Outcomes in Subjects With COVID-19 Presenting to the Emergency Department.

BACKGROUND: Severity of radiographic abnormalities on chest radiograph in subjects with COVID-19 has been shown to be associated with worse outcomes, but studies are limited by different scoring systems, sample size, subject age, and study duration. Data regarding the longitudinal evolution of radiographic abnormalities and its association with outcomes are scarce. We sought to evaluate these questions using a well-validated scoring system (the Radiographic Assessment of Lung Edema [RALE] score) using data over 6 months from a large, multihospital health care system. METHODS: We collected clinical and demographic data and quantified radiographic edema on chest radiograph obtained in the emergency department (ED) as well as on days 1-2 and 3-5 (in those admitted) in subjects with a nasopharyngeal swab positive for SARS-CoV-2 by polymerase chain reaction (PCR) visiting the ED for coronavirus disease 2019 (COVID)-19-related complaints between March-September 2020. We examined the association of baseline and longitudinal evolution of radiographic edema with severity of hypoxemia and clinical outcomes. RESULTS: Eight hundred and seventy subjects were included (median age 53.6; 50.8% female). Inter-rate agreement for RALE scores was excellent (interclass correlation coefficient 0.84 [95% CI 0.82-0.87], P < .001). RALE scores correlated with hypoxemia as quantified by SpO2 /FIO2 (r = -0.42, P < .001). Admitted subjects had higher RALE scores than those discharged (6 [2-11] vs 0 [0-3], P < .001). An increase of RALE score ≥ 4 was associated with worse 30-d survival (P = .006). Larger increases in the RALE score were associated with worse survival. CONCLUSIONS: The RALE score was reproducible and easily implementable in adult subjects presenting to the ED with COVID-19. Its association with physiologic parameters and outcomes at baseline and longitudinally makes it a readily available tool for prognostication and early ICU triage, particularly in patients with worsening radiographic edema.

Acute respiratory distress syndrome.

ABSTRACT: Acute respiratory distress syndrome (ARDS) is a severe, often fatal, lung condition frequently seen in patients in the ICU. ARDS is triggered by an inciting event such as pneumonia or sepsis, which is followed by an inappropriate host inflammatory response that results in pulmonary edema and impaired gas exchange, and may progress to fibrosis. With the increased spotlight and discussion focused on ARDS during the COVID-19 pandemic, healthcare providers must be able to identify and manage symptoms based on evidence-based research.

Safety and preliminary efficacy of sequential multiple ascending doses of solnatide to treat pulmonary permeability edema in patients with moderate to severe ARDS in a randomized, placebo-controlled, double-blind trial: preliminary evaluation of safety and feasibility in light of the COVID-19 pandemic.

BACKGROUND: In May 2018, the first patient was enrolled in the phase-IIb clinical trial "Safety and Preliminary Efficacy of Sequential Multiple Ascending Doses of Solnatide to Treat Pulmonary Permeability Edema in Patients with Moderate to Severe ARDS." With the onset of the COVID-19 pandemic in early 2020, the continuation and successful execution of this clinical study was in danger. Therefore, before the Data Safety Monitoring Board (DSMB) allowed proceeding with the study and enrollment of further COVID-19 ARDS patients into it, additional assessment on possible study bias was considered mandatory. METHODS: We conducted an ad hoc interim analysis of 16 patients (5 COVID-19- ARDS patients and 11 with ARDS from different causes) from the phase-IIB clinical trial. We assessed possible differences in clinical characteristics of the ARDS patients and the impact of the pandemic on study execution. RESULTS: COVID-19 patients seemed to be less sick at baseline, which also showed in higher survival rates over the 28-day observation period. Trial specific outcomes regarding pulmonary edema and ventilation parameters did not differ between the groups, nor did more general indicators of (pulmonary) sepsis like oxygenation ratio and required noradrenaline doses. CONCLUSION: The DSMB and the investigators did not find any evidence that patients suffering from ARDS due to SARS-CoV-2 may be at higher (or generally altered) risk when included in the trial, nor were there indications that those patients might influence the integrity of the study data altogether. For this reason, a continuation of the phase IIB clinical study activities can be justified. Researchers continuing clinical trials during the pandemic should always be aware that the exceptional circumstances may alter study results and therefore adaptations of the study design might be necessary.

Evaluation of Pulmonary Edema Using Ultrasound Imaging in Patients With COVID-19 Pneumonia Based on a Non-local Channel Attention ResNet.

Recent research has revealed that COVID-19 pneumonia is often accompanied by pulmonary edema. Pulmonary edema is a manifestation of acute lung injury (ALI), and may progress to hypoxemia and potentially acute respiratory distress syndrome (ARDS), which have higher mortality. Precise classification of the degree of pulmonary edema in patients is of great significance in choosing a treatment plan and improving the chance of survival. Here we propose a deep learning neural network named Non-local Channel Attention ResNet to analyze the lung ultrasound images and automatically score the degree of pulmonary edema of patients with COVID-19 pneumonia. The proposed method was designed by combining the ResNet with the non-local module and the channel attention mechanism. The non-local module was used to extract the information on characteristics of A-lines and B-lines, on the basis of which the degree of pulmonary edema could be defined. The channel attention mechanism was used to assign weights to decisive channels. The data set contains 2220 lung ultrasound images provided by Huoshenshan Hospital, Wuhan, China, of which 2062 effective images with accurate scores assigned by two experienced clinicians were used in the experiment. The experimental results indicated that our method achieved high accuracy in classifying the degree of pulmonary edema in patients with COVID-19 pneumonia by comparison with previous deep learning methods, indicating its potential to monitor patients with COVID-19 pneumonia.

C allele of rs479200 of the host EGLN1 gene - a risk factor for severe COVID-19 (pilot study) (preprint)

Abstract Background Coronavirus disease-2019 (COVID-19) symptoms can range from asymptomatic, moderate to severe manifestations that result in an overall global case fatality rate of 2-7 %. While each variant has had it challenges, and some variants are more severe than others, risk factors of severe COVID-19 are still under investigation. In this context, the host genetic predisposition is also a crucial factor to investigate. In the present study, we investigated host genotypes of the SNP rs479200 of the host EGLN1 gene, previously implicated in high altitude pulmonary edema (HAPE), some of whose symptoms such as hypoxia profoundly overlap with severe COVID-19. Methods After informed consent, 158 RT-PCR confirmed COVID-19 patients (March 2020 to June 2021) were enrolled in the study. Based on their clinical manifestations, disease severity was categorized by the clinical team. Blood samples were drawn and DNA was extracted from the clot to infer different genotypes of the SNP rs479200 of the host EGLN1 gene. PCR-RFLP analysis of the SNP rs479200 (C > T) was performed with an amplicon size of 367 bp. Various genotypes (TT, TC and CC) were assigned based on the presence/absence of a restriction site (T/GTACA) for restriction enzyme BsrGI. Allele frequencies, Hardy-Weinberg Equilibrium (HWE) and multinomial logistic regression were performed using statistical tool SPSS version 23 (IBM). Findings We observed that the severe COVID-19 category was composed of comparatively younger patients with mean age (34.9), compared to asymptomatic and moderate categories whose mean age was 49.7 and 54.3, respectively. Preponderance of males and high heterozygosity (TC) was observed across the clinical categories. Notably, the frequency of C allele (0.664) was 2-fold higher than the T allele (0.336) in severe COVID-19 patients, whereas the allele frequencies were similar in asymptomatic and moderate category of COVID-19 patients. Multinomial logistic regression showed an association of genotypes with increasing clinical severity; odds ratio (adjusted OR- 11.414 (2.564-50.812)) and (unadjusted OR- 6.214 (1.84-20.99)) for the genotype CC in severe category of COVID-19. Interestingly, the TC genotype was also found to be positively associated with severe outcome (unadjusted OR-5.816 (1.489-22.709)), indicating association of C allele in imparting the risk of severe outcome. Interpretation The study provides strong evidence that the presence of C allele of SNP (rs479200) of the EGLN1 gene associates with severity in COVID-19 patients. Thus, the presence of C allele may be a risk factor for COVID-19 severity. This study opens new avenues towards risk assessment that include EGLN1 (rs479200) genotype testing and identifying patients with C allele who might be prioritized for critical care.

SARS-CoV-2 membrane protein causes the mitochondrial apoptosis and pulmonary edema via targeting BOK.

Deaths caused by coronavirus disease 2019 (COVID-19) are largely due to the lungs edema resulting from the disruption of the lung alveolo-capillary barrier, induced by SARS-CoV-2-triggered pulmonary cell apoptosis. However, the molecular mechanism underlying the proapoptotic role of SARS-CoV-2 is still unclear. Here, we revealed that SARS-CoV-2 membrane (M) protein could induce lung epithelial cells mitochondrial apoptosis. Notably, M protein stabilized B-cell lymphoma 2 (BCL-2) ovarian killer (BOK) via inhibiting its ubiquitination and promoted BOK mitochondria translocation. The endodomain of M protein was required for its interaction with BOK. Knockout of BOK by CRISPR/Cas9 increased cellular resistance to M protein-induced apoptosis. BOK was rescued in the BOK-knockout cells, which led to apoptosis induced by M protein. M protein induced BOK to trigger apoptosis in the absence of BAX and BAK. Furthermore, the BH2 domain of BOK was required for interaction with M protein and proapoptosis. In vivo M protein recombinant lentivirus infection induced caspase-associated apoptosis and increased alveolar-capillary permeability in the mouse lungs. BOK knockdown improved the lung edema due to lentivirus-M protein infection. Overall, M protein activated the BOK-dependent apoptotic pathway and thus exacerbated SARS-CoV-2 associated lung injury in vivo. These findings proposed a proapoptotic role for M protein in SARS-CoV-2 pathogenesis, which may provide potential targets for COVID-19 treatments.

An antagonist of growth hormone-releasing hormone protects against LPS-induced increase of bronchoalveolar lavage fluid protein concentration.

Growth Hormone-Releasing Hormone (GHRH) is a neuropeptide regulating the release of Growth Hormone (GH) from the anterior pituitary gland, and acts as a growth factor in a diverse variety of tissues. GHRH antagonists (GHRHAnt) have been developed to counteract those events, and the beneficial effects of those peptides toward homeostasis have been associated with anti-inflammatory activities. Our lab is interested in delineating the mechanisms governing endothelial barrier function. Our goal is to establish new grounds on the development of efficient countermeasures against Acute Respiratory Distress Syndrome (ARDS), which has been associated with thousands of deaths worldwide due to COVID-19. Herein we demonstrate in vivo that GHRHAnt suppresses LPS-induced increase in bronchoalveolar lavage fluid (BALF) protein concentration, thus protecting the lungs against edema and inflammation.