Urokinase-Type Plasminogen Activator Receptor (uPAR) in Inflammation and Disease: A Unique Inflammatory Pathway Activator.

The urokinase-type plasminogen activator receptor (uPAR) is a unique protease binding receptor, now recognized as a key regulator of inflammation. Initially, uPA/uPAR was considered thrombolytic (clot-dissolving); however, recent studies have demonstrated its predominant immunomodulatory functions in inflammation and cancer. The uPA/uPAR complex has a multifaceted central role in both normal physiological and also pathological responses. uPAR is expressed as a glycophosphatidylinositol (GPI)-linked receptor interacting with vitronectin, integrins, G protein-coupled receptors, and growth factor receptors within a large lipid raft. Through protein-to-protein interactions, cell surface uPAR modulates intracellular signaling, altering cellular adhesion and migration. The uPA/uPAR also modifies extracellular activity, activating plasminogen to form plasmin, which breaks down fibrin, dissolving clots and activating matrix metalloproteinases that lyse connective tissue, allowing immune and cancer cell invasion and releasing growth factors. uPAR is now recognized as a biomarker for inflammatory diseases and cancer; uPAR and soluble uPAR fragments (suPAR) are increased in viral sepsis (COVID-19), inflammatory bowel disease, and metastasis. Here, we provide a comprehensive overview of the structure, function, and current studies examining uPAR and suPAR as diagnostic markers and therapeutic targets. Understanding uPAR is central to developing diagnostic markers and the ongoing development of antibody, small-molecule, nanogel, and virus-derived immune-modulating treatments that target uPAR.

Viral SERPINS-A Family of Highly Potent Immune-Modulating Therapeutic Proteins.

Serine protease inhibitors, SERPINS, are a highly conserved family of proteins that regulate serine proteases in the central coagulation and immune pathways, representing 2-10% of circulating proteins in the blood. Serine proteases form cascades of sequentially activated enzymes that direct thrombosis (clot formation) and thrombolysis (clot dissolution), complement activation in immune responses and also programmed cell death (apoptosis). Virus-derived serpins have co-evolved with mammalian proteases and serpins, developing into highly effective inhibitors of mammalian proteolytic pathways. Through interacting with extracellular and intracellular serine and cysteine proteases, viral serpins provide a new class of highly active virus-derived coagulation-, immune-, and apoptosis-modulating drug candidates. Viral serpins have unique characteristics: (1) function at micrograms per kilogram doses; (2) selectivity in targeting sites of protease activation; (3) minimal side effects at active concentrations; and (4) the demonstrated capacity to be modified, or fine-tuned, for altered protease targeting. To date, the virus-derived serpin class of biologics has proven effective in a wide range of animal models and in one clinical trial in patients with unstable coronary disease. Here, we outline the known viral serpins and review prior studies with viral serpins, considering their potential for application as new sources for immune-, coagulation-, and apoptosis-modulating therapeutics.

RNA Virus Gene Signatures Detected in Patients With Cardiomyopathy After Chemotherapy; A Pilot Study.

Background: Viral infections are pervasive and leading causes of myocarditis. Immune-suppression after chemotherapy increases opportunistic infections, but the incidence of virus-induced myocarditis is unknown. Objective: An unbiased, blinded screening for RNA viruses was performed after chemotherapy with correlation to cardiac function. Methods: High-throughput sequencing of RNA isolated from blood samples was analyzed following chemotherapy for hematological malignancies (N = 28) and compared with left ventricular ejection fraction (LVEF). Results: On initial rigorous analysis, low levels of influenza orthomyxovirus and avian paramyxovirus sequences were detectable, but without significant correlation to LVEF (r = 0.208). A secondary broad data mining analysis for virus sequences, without filtering human sequences, detected significant correlations for paramyxovirus with LVEF after chemotherapy (r = 0.592, P < 0.0096). Correlations were similar for LVEF pre- and post- chemotherapy for orthomyxovirus (R = 0.483, P < 0.0421). Retrovirus detection also correlated with LVEF post (r = 0.453, p < 0.0591), but not pre-chemotherapy, but is suspect due to potential host contamination. Detectable phage and anellovirus had no correlation. Combined sequence reads (all viruses) demonstrated significant correlation (r = 0.621, P < 0.0078). Reduced LVEF was not associated with chemotherapy (P = NS). Conclusions: This is the first report of RNA virus screening in circulating blood and association with changes in cardiac function among patients post chemotherapy, using unbiased, blinded, high-throughput sequencing. Influenza orthomyxovirus, avian paramyxovirus and retrovirus sequences were detectable in patients with reduced LVEF. Further analysis for RNA virus infections in patients with cardiomyopathy after chemotherapy is warranted.

Surgical and clinical efficacy of minimally invasive sacroiliac joint fusion surgery: a meta-analysis protocol.

INTRODUCTION: Sacroiliac joint (SIJ) dysfunction has been shown to cause significant morbidity. Current treatment includes conservative management and surgical intervention. Previously published data reporting clinical and surgical outcomes reached conflicting conclusions. This protocol aims to conduct a meta-analysis to determine fusion rates and patient-reported outcomes of minimally invasive (MIS) SIJ fusions compared with conservative treatment. METHODS AND ANALYSIS: We drafted our protocol according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. We will search PubMed, Embase and the Cochrane Library, supplemented by manual search when necessary. Two independent reviewers will screen for eligibility by title/abstract, then full text, arbitrated by a third reviewer if necessary. The two reviewers will carry out a risk of bias assessment using the Cochrane Collaboration Risk of Bias tool for randomised controlled trial and the Methodological Index for Non-Randomised Studies tool for observational cohort studies. A third reviewer will arbitrate any disagreement. We will perform data synthesis using Review Manager (RevMan for Windows, V.5.4.1, The Cochrane Collaboration, 2020) and Comprehensive Meta-Analysis (V.3.3.070). Meta-bias will be evaluated and confidence determined using the Grading of Recommendations, Assessment, Development and Evaluation guidelines. ETHICS AND DISSEMINATION: Ethical approval for this review will not be required as no patient data is being collected. The results of this study will be submitted for publication in peer-reviewed journals. PROSPERO REGISTRATION NUMBER: CRD42021273481.

Distinct Coagulopathy With Myocardial Injury and Pulmonary Embolism in COVID-19.

In this article, we report a case of a 61-year-old male who was diagnosed with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), presenting with acute respiratory distress syndrome requiring intubation and hemodynamic support, marked D-Dimer and troponin I elevation, worsening ST-elevation myocardial infarction on repeat electrocardiograms, and a negative coronary angiogram ruling out a coronary artery thrombosis or occlusion. With worsening diffuse ST-segment elevation on electrocardiograms and reduced ejection fraction on echocardiography in the setting of systemic inflammation, fulminant myocarditis was highly suspected. Despite optimal medical treatment, the patient's condition deteriorated and was complicated by cardiac arrest that failed resuscitation. Although myocarditis was initially suspected, the autopsy revealed no evidence of myocarditis or pericarditis but did demonstrate multiple microscopic sites of myocardial ischemia together with thrombi in the left atrium and pulmonary vasculature. Additionally, scattered microscopic cardiomyocyte necrosis with pathological diagnosis of small vessel micro-thrombotic occlusions. These findings are potentially exacerbated by inflammation-induced coagulopathy, hypoxia, hypotension, and stress, that is, a multifactorial etiology. Further research and an improved understanding are needed to define the precise pathophysiology of the coagulopathic state causing widespread micro-thrombosis with subsequent myocardial and pulmonary injury.

Incidental Finding of a Large Right Atrial Thrombus in a Patient With Cerebral Lymphoma.

Right atrial (RA) masses are rare, challenging to diagnose, and potentially life-threatening with high mortality if untreated. We present a patient presenting with diffuse large B-cell lymphoma in the brain that was incidentally found to have a large RA mass. For a better definition of the RA mass, extensive workup using multimodality imaging including chest computed tomography, transthoracic echocardiography, transesophageal echocardiography, cardiac magnetic resonance imaging, and left heart catheterization was warranted. The imaging demonstrated a large RA mass extending through the tricuspid valve into the right ventricle and superior and inferior vena cava without a mobile component. The mass was then successfully resected, and further histology examination was performed to rule out lymphoma and rare subtypes of diffuse large B-cell lymphoma. The comprehensive workup proved the RA mass to be a calcified thrombus rather than a direct metastatic spread of lymphoma.

Serine Proteases and Chemokines in Neurotrauma: New Targets for Immune Modulating Therapeutics in Spinal Cord Injury.

Progressive neurological damage after brain or spinal cord trauma causes loss of motor function and treatment is very limited. Clotting and hemorrhage occur early after spinal cord (SCI) and traumatic brain injury (TBI), inducing aggressive immune cell activation and progressive neuronal damage. Thrombotic and thrombolytic proteases have direct effects on neurons and glia, both healing and also damaging bidirectional immune cell interactions. Serine proteases in the thrombolytic cascade, tissue- and urokinase-type plasminogen activators (tPA and uPA), as well as the clotting factor thrombin, have varied effects, increasing neuron and glial cell growth and migration (tPA), or conversely causing apoptosis (thrombin) and activating inflammatory cell responses. tPA and uPA activate plasmin and matrix metalloproteinases (MMPs) that break down connective tissue allowing immune cell invasion, promoting neurite outgrowth. Serine proteases also activate chemokines. Chemokines are small proteins that direct immune cell invasion but also mediate neuron and glial cell communication. We are investigating a new class of therapeutics, virus-derived immune modulators; One that targets coagulation pathway serine proteases and a second that inhibits chemokines. We have demonstrated that local infusion of these biologics after SCI reduces inflammation providing early improved motor function. Serp-1 is a Myxomavirus-derived serine protease inhibitor, a serpin, that inhibits both thrombotic and thrombolytic proteases. M-T7 is a virus-derived chemokine modulator. Here we review the roles of thrombotic and thrombolytic serine proteases and chemoattractant proteins, chemokines, as potential therapeutic targets for SCI. We discuss virus-derived immune modulators as treatments to reduce progressive inflammation and ongoing nerve damage after SCI.

Elective Inguinal Hernia Surgery in the Setting of Unfollowed Congenital Complete Heart Block With No Postponement.

Most preoperatively discovered complete heart block cases without cardiac clearance in a non-emergent situation are managed with deferral of elective surgery until a cardiology workup can be completed. The medical consequences of surgical delays can manifest in increased costs to the healthcare system via the treatment of more advanced disease, often requiring more intense and more costly treatment in addition to the emotional burden of delay on a patient that has been waiting months for a particular surgery. Delays in surgery have real impacts on patient health outcomes, hospital finances, and patient satisfaction. We present a rare case in which a proactive anesthesiologist was able to take measures to stratify patient safety risk and safely prevent the delay of the surgery in an asymptomatic and unfollowed congenital third-degree heart block patient. The anesthesiologist demonstrates the use of established guidelines for non-elective noncardiac surgery to safely and effectively prevent the delay of an elective inguinal hernia repair in the setting of a situation that normally warrants its delay. Using these pre- and intraoperative measures, the anesthesiologist was able to prevent the delay of elective surgery, and this should set a precedent of the necessary steps involved to safely manage a patient with an unfollowed third-degree congenital heart block.

Chronological Impact of Earthquakes on Blood Pressure: A Literature Review and Retrospective Study of Hypertension in Haiti Before and After the 2010 Earthquake.

Objective: We review prior studies on the incidence of hypertension (HTN) after earthquakes and present a retrospective analysis of HTN after the 2010 earthquake in Haiti. Methods: Prior reports on HTN incidence were reviewed and a retrospective chart review for diagnosis of HTN in 4,308 patient charts was performed over a 7 year period (five clinics). A retrospective cohort study (RCS) was then performed on 11 patients with linear follow-up. Results: The Literature review revealed a significant increase in acute and subacute HTN following earthquakes. However, the chronic effects of earthquakes varied. Our chart review uncovered no significant difference in diagnosed HTN in a Fort-Liberté clinic 128 kilometers (km) distant and 4 weeks post-event. A secondary linear RCS for 11 individuals, prior to and after the earthquake, also did not detect a significant change in HTN prevalence. Conclusion: Prior studies demonstrate acute and subacute, increases in HTN after earthquakes, but late changes have varied. Retrospective studies in the Fort-Liberté clinic, 128 km distant and 4 weeks post-event, revealed no significant change in HTN, confirming prior findings that changes in HTN after earthquakes are early and local events. Further work examining HTN after earthquakes is needed to improve early health care after natural disasters.