Cytokine release syndrome in severe COVID-19 Moore, John B; June, Carl H
Science (American Association for the Advancement of Science),
05/2020, Letnik:
368, Številka:
6490
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Lessons from arthritis and cell therapy in cancer patients point to therapy for severe disease
In December 2019, a new strain of coronavirus, severe acute respiratory syndrome–coronavirus 2 ...(SARS-CoV-2), was recognized to have emerged in Wuhan, China. Along with SARS-CoV and Middle East respiratory syndrome–coronavirus (MERS-CoV), SARS-CoV-2 is the third coronavirus to cause severe respiratory illness in humans, called coronavirus disease 2019 (COVID-19). This was recognized as a pandemic by the World Health Organization (WHO) in March 2020 and has had considerable global economic and health impacts. Although the situation is rapidly evolving, severe disease manifested by fever and pneumonia, leading to acute respiratory distress syndrome (ARDS), has been described in up to 20% of COVID-19 cases. This is reminiscent of cytokine release syndrome (CRS)–induced ARDS and secondary hemophagocytic lymphohistiocytosis (sHLH) observed in patients with SARS-CoV and MERS-CoV as well as in leukemia patients receiving engineered T cell therapy. Given this experience, urgently needed therapeutics based on suppressing CRS, such as tocilizumab, have entered clinical trials to treat COVID-19.
A prothrombotic coagulopathy is commonly found in critically ill COVID‐19 patients with acute respiratory distress syndrome (ARDS). A unique feature of COVID‐19 respiratory failure is a relatively ...preserved lung compliance and high Alveolar‐arterial oxygen gradient, with pathology reports consistently demonstrating diffuse pulmonary microthrombi on autopsy, all consistent with a vascular occlusive etiology of respiratory failure rather than the more classic findings of low‐compliance in ARDS. The COVID‐19 pandemic is overwhelming the world’s medical care capacity with unprecedented needs for mechanical ventilators and high rates of mortality once patients progress to needing mechanical ventilation, and in many environments including in parts of the United States the medical capacity is being exhausted. Fibrinolytic therapy has previously been used in a Phase 1 clinical trial that led to reduced mortality and marked improvements in oxygenation. Here we report a series of three patients with severe COVID‐19 respiratory failure who were treated with tissue plasminogen activator. All three patients had a temporally related improvement in their respiratory status, with one of them being a durable response.
One of water's unsolved puzzles is the question of what determines the lowest temperature to which it can be cooled before freezing to ice. The supercooled liquid has been probed experimentally to ...near the homogeneous nucleation temperature, T(H) ≈ 232 K, yet the mechanism of ice crystallization-including the size and structure of critical nuclei-has not yet been resolved. The heat capacity and compressibility of liquid water anomalously increase on moving into the supercooled region, according to power laws that would diverge (that is, approach infinity) at ~225 K (refs 1, 2), so there may be a link between water's thermodynamic anomalies and the crystallization rate of ice. But probing this link is challenging because fast crystallization prevents experimental studies of the liquid below T(H). And although atomistic studies have captured water crystallization, high computational costs have so far prevented an assessment of the rates and mechanism involved. Here we report coarse-grained molecular simulations with the mW water model in the supercooled regime around T(H) which reveal that a sharp increase in the fraction of four-coordinated molecules in supercooled liquid water explains its anomalous thermodynamics and also controls the rate and mechanisms of ice formation. The results of the simulations and classical nucleation theory using experimental data suggest that the crystallization rate of water reaches a maximum around 225 K, below which ice nuclei form faster than liquid water can equilibrate. This implies a lower limit of metastability of liquid water just below T(H) and well above its glass transition temperature, 136 K. By establishing a relationship between the structural transformation in liquid water and its anomalous thermodynamics and crystallization rate, our findings also provide mechanistic insight into the observed dependence of homogeneous ice nucleation rates on the thermodynamics of water.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Background Fibrinolysis is a physiologic process to maintain microvascular patency by breaking down excessive fibrin clot. Hyperfibrinolysis (HF) is associated with a doubling of mortality. ...Fibrinolysis shutdown (SD), an acute impairment of fibrinolysis, has been recognized as a risk factor for increased mortality. The purpose of this study was to assess the incidence and outcomes of fibrinolysis phenotypes in two urban trauma centers. Study Design Injured patients admitted 2010-2013, who were ≥18 years of age, had an injury severity score (ISS) >15 were included in the analysis. Admission fibrinolysis phenotypes were determined by the clot lysis at 30 minutes (LY30): SD ≤0.8%, physiologic 0.9-2.9%, HF ≥3%. Logistic regression was used to adjust for age, arrival blood pressure, ISS, mechanism, and facility. Results 2540 patients met inclusion. Median age was 39(IQR 26-55) and median ISS was 25(IQR 20-33) with a mortality rate of 21%. Fibrinolysis shutdown was the most common phenotype (46%) followed by physiologic (36%) and hyperfibrinolysis(18%). HF was associated with the highest death rate (34%), followed by SD(22%), and physiologic (14%, p<0.001). The risk of mortality remained increased for HF(OR=3.3, 95%C: 2.4-4.6, p<0.0001) and SD(OR 1.6 95%CI 1.3-2.1, p=0.0003) compared to physiologic when adjusting for age, ISS, mechanism, head injury, and blood pressure (AUROC=0.82, 95% CI 0.80-0.84). Conclusions Fibrinolysis SD is the most common phenotype upon admission and is associated with increased mortality. Moreover, these data provide additional evidence of distinct phenotypes of coagulation impairment and that individualized hemostatic therapy may be required.
Context. The consistency of planet formation models suffers from the disconnection between the regime of small and large bodies. This is primarily caused by so-called growth barriers: the direct ...growth of larger bodies is halted at centimetre-sized objects and particular conditions are required for the formation of larger, gravitationally bound planetesimals. Aims. We aim to connect models of dust evolution and planetesimal formation to identify regions of protoplanetary discs that are favourable for the formation of kilometre-sized bodies and the first planetary embryos. Methods. We combine semi-analytical models of viscous protoplanetary disc evolution, dust growth and drift including backreaction of the dust particles on the gas, and planetesimal formation via the streaming instability into one numerical code. We investigate how planetesimal formation is affected by the mass of the protoplanetary disc, its initial dust content, and the stickiness of dust aggregates. Results. We find that the dust growth and drift leads to a global redistribution of solids. The pile-up of pebbles in the inner disc provides local conditions where the streaming instability is effective. Planetesimals form in an annulus with its inner edge lying between 0.3 AU and 1 AU and its width ranging from 0.3 AU to 3 AU. The resulting surface density of planetesimals follows a radial profile that is much steeper than the initial disc profile. These results support formation of terrestrial planets in the solar system from a narrow annulus of planetesimals, which reproduces their peculiar mass ratios.
Animal models of fibrotic lung disease B Moore, Bethany; Lawson, William E; Oury, Tim D ...
American journal of respiratory cell and molecular biology
49, Številka:
2
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Interstitial lung fibrosis can develop as a consequence of occupational or medical exposure, as a result of genetic defects, and after trauma or acute lung injury leading to fibroproliferative acute ...respiratory distress syndrome, or it can develop in an idiopathic manner. The pathogenesis of each form of lung fibrosis remains poorly understood. They each result in a progressive loss of lung function with increasing dyspnea, and most forms ultimately result in mortality. To better understand the pathogenesis of lung fibrotic disorders, multiple animal models have been developed. This review summarizes the common and emerging models of lung fibrosis to highlight their usefulness in understanding the cell-cell and soluble mediator interactions that drive fibrotic responses. Recent advances have allowed for the development of models to study targeted injuries of Type II alveolar epithelial cells, fibroblastic autonomous effects, and targeted genetic defects. Repetitive dosing in some models has more closely mimicked the pathology of human fibrotic lung disease. We also have a much better understanding of the fact that the aged lung has increased susceptibility to fibrosis. Each of the models reviewed in this report offers a powerful tool for studying some aspect of fibrotic lung disease.
IL-17 in the lung: the good, the bad, and the ugly Gurczynski, Stephen J; Moore, Bethany B
American journal of physiology. Lung cellular and molecular physiology,
01/2018, Letnik:
314, Številka:
1
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The IL-17 family of cytokines has emerged over the last two decades as a pleiotropic group of molecules that function in a wide variety of both beneficial and detrimental (pathological) processes, ...mainly in mucosal barrier tissue. The beneficial effects of IL-17 expression are especially important in the lung, where exposure to foreign agents is abundant. IL-17A plays an important role in protection from both extracellular bacteria and fungi, as well as viruses that infect cells of the mucosal tracts. IL-17 coregulated cytokines, such as IL-22, are involved in maintaining epithelial cell homeostasis and participate in epithelial cell repair/regeneration following inflammatory insults. Thus, the IL-17/IL-22 axis is important in both responding to, and recovering from, pathogens. However, aberrant expression or overexpression of IL-17 cytokines contributes to a number of pathological outcomes, including asthma, pneumonitis, and generation or exacerbation of pulmonary fibrosis. This review covers the good, bad, and ugly aspects of IL-17 in the lung.
The COVID-19 pandemic has introduced a global public health threat unparalleled in our history. The most severe cases are marked by ARDS attributed to microvascular thrombosis. Hypercoagulability, ...resulting in a profoundly prothrombotic state, is a distinct feature of COVID-19 and is accentuated by a high incidence of fibrinolysis shutdown. The aims of this review were to describe the manifestations of fibrinolysis shutdown in COVID-19 and its associated outcomes, review the molecular mechanisms of dysregulated fibrinolysis associated with COVID-19, and discuss potential implications and therapeutic targets for patients with severe COVID-19.
Viral infections are important contributors to exacerbation of asthma and chronic obstructive pulmonary disease; however, the role of viruses in the pathogenesis of idiopathic pulmonary fibrosis ...(IPF) is less clear. This likely reflects that fact that IPF acute exacerbations are defined clinically as "noninfectious," and little attention has been paid to the outcomes of patients with IPF with diagnosed infections. However, accumulating evidence suggests that infections (both bacterial and viral) may influence disease outcomes either as exacerbating agents or initiators of disease. Support for a viral role in disease initiation comes from studies demonstrating the presence of herpesviral DNA and epithelial cell stress in the lungs of asymptomatic relatives at risk for developing familial IPF. In addition, the number of studies that can associate viral (especially herpesviral) signatures in the lung with the development of IPF is steadily growing, and activated leukocyte signatures in patients with IPF provide further support for infectious processes driving IPF progression. Animal modeling has been used to better understand how a gamma herpesvirus infection can modulate the pathogenesis of lung fibrosis and has demonstrated that preceding infections appear to reprogram lung epithelial cells during latency to produce profibrotic factors, making the lung more susceptible to subsequent fibrotic insult, whereas exacerbations of existing fibrosis, or infections in susceptible hosts, involve active viral replication and are influenced by antiviral therapy. In addition, there is new evidence that bacterial burden in the lungs of patients with IPF may predict a poor prognosis.
The development of culture-independent techniques for microbiological analysis has uncovered the previously unappreciated complexity of the bacterial microbiome at various anatomic sites. The ...microbiome of the lung has relatively less bacterial biomass when compared with the lower gastrointestinal tract yet displays considerable diversity. The composition of the lung microbiome is determined by elimination, immigration, and relative growth within its communities. Chronic lung disease alters these factors. Many forms of chronic lung disease demonstrate exacerbations that drive disease progression and are poorly understood. Mounting evidence supports ways in which microbiota dysbiosis can influence host defense and immunity, and in turn may contribute to disease exacerbations. Thus, the key to understanding the pathogenesis of chronic lung disease may reside in deciphering the complex interactions between the host, pathogen, and resident microbiota during stable disease and exacerbations. In this brief review we discuss new insights into these labyrinthine relationships.
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