The COVID-19 pandemic has had devastating medical and economic consequences globally. The severity of COVID-19 is related, in a large measure, to the extent of pulmonary involvement. The role of chest CT in the management of patients with COVID-19 has evolved since the onset of the pandemic. Specifically, the description of CT findings, use of CT chest in various acute and subacute settings and its usefulness in predicting chronic disease have been better defined. We performed a review of published data on CT scans in COVID-19 patients. A summary of the range of imaging findings, from typical to less common abnormalities is provided. Familiarity with these findings may facilitate in the diagnosis and management of this disease. A comparison of sensitivity and specificity of CT chest with RT-PCR testing highlights the potential role of CT imaging in difficult to diagnose cases of Covid-19. The utility of CT imaging to assess prognosis, guide management, and identify acute pulmonary complications associated with SARS-COV-2 is highlighted. Beyond the acute stage, it is important for clinicians to recognize pulmonary parenchymal abnormalities, progressive fibrotic lung disease and vascular changes that may be responsible for persistent respiratory symptoms. A large collection of multi institutional images has been included to elucidate the CT findings described.

Hypoxia leads to free radical production, which has a pivotal role in the pathophysiology of pulmonary hypertension (PH). We hypothesized that treatment with extracellular superoxide dismutase (EC-SOD) could ameliorate the development of PH induced by hypoxia. In vitro studies using pulmonary microvascular endothelial cells showed that cells transfected with EC-SOD had significantly less accumulation of xanthine oxidase and reactive oxygen species than nontransfected cells after hypoxia exposure for 24 h. To study the prophylactic role of EC-SOD, adult male wild-type (WT) and transgenic (TG) mice, with lung-specific overexpression of human EC-SOD (hEC-SOD), were exposed to fraction of inspired oxygen (FiO 2 ) 10% for 10 d. After exposure, right ventricular systolic pressure (RVSP), right ventricular mass (RV/S + LV), pulmonary vascular wall thickness (PVWT) and pulmonary artery contraction/relaxation were assessed. TG mice were protected against PH compared with WT mice with significantly lower RVSP (23.9 ± 1.24 versus 47.2 ± 3.4), RV/S + LV (0.287 ± 0.015 versus 0.335 ± 0.022) and vascular remodeling, indicated by PVWT (14.324 ± 1.107 versus 18.885 ± 1.529). Functional studies using pulmonary arteries isolated from mice indicated that EC-SOD prevents hypoxia-mediated attenuation of nitric oxide-induced relaxation. Therapeutic potential was assessed by exposing WT mice to FiO 2 10% for 10 d. Half of the group was transfected with plasmid containing cDNA encoding human EC-SOD. The remaining animals were transfected with empty vector. Both groups were exposed to FiO 2 10% for a further 10 d. Transfected mice had significantly reduced RVSP (18.97 ± 1.12 versus 41.3 ± 1.5), RV/S + LV (0.293 ± 0.012 versus 0.372 ± 0.014) and PVWT (12.51 ± 0.72 versus 18.98 ± 1.24). On the basis of these findings, we concluded that overexpression of EC-SOD prevents the development of PH and ameliorates established PH.

. 20-HETE-induced mitochondrial superoxide production and inflammatory phenotype in vascular smooth muscle is prevented by glucose-6-phosphate dehydrogenase inhibition. Am J Physiol Heart Circ Physiol 310: H1107-H1117, 2016. First published February 26, 2016 doi:10.1152/ajpheart.00961.2015 produced by cytochrome P-450 monooxygenases in NA-DPH-dependent manner is proinflammatory, and it contributes to the pathogenesis of systemic and pulmonary hypertension. In this study, we tested the hypothesis that inhibition of glucose-6-phosphate dehydrogenase (G6PD), a major source of NADPH in the cell, prevents 20-HETE synthesis and 20-HETE-induced proinflammatory signaling that promotes secretory phenotype of vascular smooth muscle cells. Lipidomic analysis indicated that G6PD inhibition and knockdown decreased 20-HETE levels in pulmonary arteries as well as 20-HETEinduced 1) mitochondrial superoxide production, 2) activation of mitogen-activated protein kinase 1 and 3, 3) phosphorylation of ETS domain-containing protein Elk-1 that activate transcription of tumor necrosis factor-␣ gene (Tnfa), and 4) expression of tumor necrosis factor-␣ (TNF-␣). Moreover, inhibition of G6PD increased protein kinase G1␣ activity, which, at least partially, mitigated superoxide production and Elk-1 and TNF-␣ expression. Additionally, we report here for the first time that 20-HETE repressed miR-143, which suppresses Elk-1 expression, and miR-133a, which is known to suppress synthetic/secretory phenotype of vascular smooth muscle cells. In summary, our findings indicate that 20-HETE elicited mitochondrial superoxide production and promoted secretory phenotype of vascular smooth muscle cells by activating MAPK1-Elk-1, all of which are blocked by inhibition of G6PD.20-HETE; TNF-␣; elk-1; mitogen-activated protein kinase 1 and 3; extracellular signal regulated kinase 2 and 1; protein kinase G; miRs 20-HYDROXYEICOSATETRAEONIC acid (20-HETE), the -hydroxylation metabolite of arachidonic acid (AA), is produced by cytochrome P-450 monooxygenases of the (CYP4A and CYP4F gene) families in an NADPH-dependent manner (49). 20-HETE is proinflammatory and it regulates vascular and renal function (49). It also plays a critical role in the pathogenesis of systemic hypertension, renal stenosis, and atherosclerosis (27,63,65). 20-HETE increased by hypoxia inhibits hypoxia-induced pulmonary artery constriction (69). However, its role in the hypoxia-induced inflammation of pulmonary arteries or lungs is yet unclear. NEWS & NOTEWORTHY 20-Hydroxyeicosatetraeonic acid (20-HETE) plays a criticalRecently, our laboratory also found that 20-HETE is involved in promoting prolonged hypoxia-induced pulmonary vasoconstriction and that glucose-6-phosphate dehydrogenase (G6PD), which is a major producer of NADPH in the cell, and cytochrome P-450 monooxygenase enzymes are functionally coupled in vascular smooth muscle tissue (unpublished observations). G6PD inhibition relaxes pulmonary arteries by decreasing intracellular calcium (20), prevents switching of vascular smooth ...