Rationale and Objectives: To retrospectively analyze the chest imaging findings in patients with coronavirus disease 2019 (COVID-19) on thin-section CT.Materials and Methods: Fifty-three patients with confirmed COVID-19 infection underwent thin-section CT examination. Two chest radiologists independently evaluated the imaging in terms of distribution, ground-glass opacity (GGO), consolidation, air bronchogram, stripe, enlarged mediastinal lymph node, and pleural effusion.Results: Fourty-seven cases (88.7%) had findings of COVID-19 infection, and the other six (11.3%) were normal. Among the 47 cases, 78.7% involved both lungs, and 93.6% had peripheral infiltrates distributed along the subpleural area. All cases showed GGO, 59.6% of which were round and 40.4% patchy. Other imaging features included "crazy-paving pattern" (89.4%), consolidation (63.8%), and air bronchogram (76.6%). Air bronchograms were observed within GGO (61.7%) and consolidation (70.3%). Neither enlarged mediastinal lymph nodes nor pleural effusion were present. Thirty-three patients (62.3%) were followed an average interval of 6.2 § 2.9 days. The lesions increased in 75.8% and resorbed in 24.2% of patients.Conclusion: COVID-19 showed the pulmonary lesions in patients infected with COVID-19 were predominantly distributed peripherally in the subpleural area.

Background and PurposeStroke of large-artery atherosclerosis and small-artery occlusion are two main subtypes of stroke according to TOAST classification. The underlying mechanisms of how these two subtypes affect dynamic cerebral autoregulation (dCA) might be heterogeneous, resulting in varied clinical conditions and outcomes. We therefore studied the pattern of dCA in these two subtypes.MethodsForty-one patients with acute unilateral middle cerebral artery (MCA) territory stroke (15 with ipsilateral large-artery atherosclerosis and 26 with small-artery occlusion) and 20 healthy volunteers were enrolled. Non-invasive continuous cerebral blood flow velocity and arterial blood pressure were recorded simultaneously from each subject in supine position using transcranial Doppler on MCA bilaterally and servo-controlled plethysmograph on the middle finger, respectively. Transfer function analysis was applied to derive autoregulatory parameters, gain, phase difference (PD), and slope of step response.ResultsIn the large-artery atherosclerosis group, PD in affected hemisphere was 42.9±18.5 degree, which is significantly lower than the unaffected hemisphere (72.4±29.9 degree, P<0.01), and the healthy group (P<0.01). However, PD is similar in the unaffected hemisphere and healthy group (P>0.1). In the small-artery occlusion group, PD in the affected hemisphere was similar to that in the contralateral hemisphere (33.8±17.9 vs. 32.6±21.1 degree, P>0.1), both sides were significantly lower than the healthy group (all P<0.001).The results of the slope of step response agree with the findings in PD.ConclusionsDCA in different subtypes of acute ischemic stroke is heterogeneous, which might be attributed to the varied pathologic changes of cerebral blood vessels.

In response to a number of stresses, including nutrient deprivation, General Control Nonderepressible 2 kinase (GCN2) attenuates mRNA translation by phosphorylating eukaryotic initiation factor 2 alpha (eIF2αSer51). Energy starvation is known to exacerbate congestive heart failure (CHF) and eIF2αSer51 phosphorylation is increased in the failing heart. However, the impact of GCN2 during the evolution of CHF has not been tested. In this study we examined the influence of GCN2 expression in response to a cardiac stress by inducing chronic pressure overload with Transverse Aortic Constriction (TAC) in Wild Type (WT) and GCN2 knockout (GCN2−/−) mice. Under basal conditions, GCN2−/− had normal LV structure or function but following TAC, demonstrated less contractile dysfunction, less increase of lung weight, less increase of lung inflammation and vascular remodeling, and less myocardial apoptosis and fibrosis compared with WT mice, despite an equivalent degree of LV hypertrophy. As expected, GCN2−/− attenuated TAC induced cardiac eif2αSer51 phosphorylation and preserved Sarcoplasmic reticulum Ca2+ ATPase (Serca2a) expression compared with WT mice. Interestingly, expression of the anti-apoptotic protein Bcl-2 was significantly elevated in GCN2−/− hearts, while in isolated neonatal cardiomyocytes, selective knockdown of GCN2 increased Bcl-2 protein expression and enhanced myocyte resistance to an apoptotic stress. Collectively, our data support the notion that GCN2 impairs the ventricular adaptation to chronic pressure overload by reducing Bcl-2 expression and increasing cardiomyocyte susceptibility to apoptotic stimuli. Our findings suggest that strategies to reduce GCN2 activity in cardiac tissue may be a novel approach to attenuate congestive heart failure development.

Background and PurposeThe relationship between right-to-left shunts (RLS) and migraine and cryptogenic stroke is not well understood. In this study, we investigated whether RLS are associated with impairment of dynamic cerebral autoregulation (dCA), which may play a role in migraine and cryptogenic stroke.MethodsSixty-six migraineurs were enrolled in the study, including 36 non-RLS patients and 30 RLS patients. Non-invasive continuous cerebral blood flow velocity and arterial blood pressure were recorded simultaneously from each patient by using transcranial Doppler and servo-controlled plethysmograph, respectively. Transfer function analysis was applied to derive autoregulatory parameters of gain, phase difference (PD), and autoregulation index.ResultsThe PD in migraineurs with RLS was 50.6±22.9 degrees, which was significantly lower than that observed in the non-RLS group (67.2±18.2 degrees, P<0.001). The PD in the large RLS group (45.4±22.6 degrees) was significantly lower than that of the small RLS group (64.9±17.1 degrees, P<0.01) and non-RLS group (P<0.001); however, the PD in the small RLS group was similar to that of the non-RLS group. The PD in the permanent group (48.8±19.9 degrees) was similar to that of the latent group (52.6±26.1 degrees), and both were significantly lower than that of the non-RLS group (P<0.05). The autoregulation index results were similar to the PD findings.ConclusionsdCA is impaired in migraineurs with large RLS, and this may represent a potential mechanism linking RLS, migraine, and cryptogenic stroke.

We aimed to retrospectively analyze the imaging changes detected in the follow-up of coronavirus disease 2019 (COVID-19) patients on thin-section computed tomography (CT). METHODSWe included 54 patients diagnosed with COVID-19. The mean interval between the initial and follow-up CT scans was 7.82±3.74 days. Patients were divided into progression and recovery groups according to their outcomes. We evaluated CT images in terms of distribution of lesions and imaging manifestations. The manifestations included ground-glass opacity (GGO), crazy-paving pattern, consolidation, irregular line, and air bronchogram sign. RESULTSCOVID-19 lesions showed mainly subpleural distribution, which was accompanied by bronchovascular bundle distribution in nearly 30% of the patients. The lower lobes of both lungs were the most commonly involved. In the follow-up, the progression group showed more involvement of the upper lobe of the left lung than the recovery group. GGO was the most common sign. As the disease progressed, round GGO decreased and patchy GGO increased. On follow-up CT, consolidation increased in the progression group while decreasing in the recovery group. Air bronchogram sign was more commonly observed at the initial examination (90.9%) than at follow-up (30%) in the recovery group, but there was no significant change in the progression group. Pleural effusion and lymphadenopathy were absent in the initial examination, but pleural effusion was observed in three cases after follow-up. CONCLUSIONAs COVID-19 progressed, round GGOs tended to evolve into patchy GGOs, consolidation increased, and pleural effusion could be occasionally observed. As COVID-19 resolved, the crazy-paving pattern and air bronchogram significantly decreased.

Highlights The incidence of venous thromboembolism is high among mild/moderate COVID-19 cases. Despite of thrombosis, tests for inflammatory, coagulation and biochemistry parameters were all in normal scope. The conventional method by Doppler ultrasound tend to underestimate the rate of thrombosis in comparisons to CTPA + CTV method.

P r e v i o u s s t u d i e s h a v e i d e n t i f i e d a d i v e r s eset of predisposing factors for the occurrence of hemorrhagic transformation (HT), but the independent clinical predictors of HT after intraarterial thrombolysis have not been determined. In this retrospective study, we investigated the characteristics of patients with or without HT who had received intra-arterial thrombolysis therapy, using biochemical analysis, renal function test, routine blood test, blood lipid test, coagulation blood test, liver function test, random blood glucose test, timewindow for intra-arterial thrombolysis, recanalization, National Institutes of Health Stroke Scale (NIHSS) score and systolic blood pressure before intra-arterial thrombolysis. The mortality rates were similar in the HT and non-HT groups (P = 0.944). In the singlefactor analysis, patients with a higher globulin level (P <0.002), prothrombin time activity percentage (PTA; P = 0.026), and NIHSS score (P = 0.002), had a significantly increased risk of developing HT. In the multifactor logistic regression model involving globulin level, PTA, white blood cell count, and NIHSS score, the globulin level (P <0.001; OR, 1.185; 95% confidence interval [CI], 1.090-1.288), PTA (P = 0.018; OR, 1.016; 95% CI, 1.003-1.029), white blood cell count (P = 0.025; OR, 1.097; 95% CI, 1.012-1.190) and NIHSS score (P = 0.003; OR, 1.097; 95% CI, 1.031-1.166) were significantly increased in the HT group. The increase in globulin level is an independent risk factor for HT in patients receiving intra-arterial thrombolysis. The possible mechanisms may involve inflammatory cytokines, matrix metalloproteinase 9, and positive acute-phase reactants synthesized by the liver.

DCE-MRI is useful to differentiate the metastatic LNs from benign LNs. Sizes of LNs has no effect on parameters.