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Acute coronary syndrome (ACS) is mainly caused by atherosclerotic coronary artery disease (CAD); however, it can also occur in patients with non-atherosclerotic CAD. Conventional coronary angiography only shows the lumen of arteries, indicating the presence of stenosis or dilatation. Thus, it has limited value in evaluating the coronary artery wall and offers low specificity for diagnosing CAD. Coronary CT angiography provides additional information, including the depiction of the concerned vessel and the aorta, as well as the pulmonary artery, which permits the diagnosis of non-atherosclerotic CAD and the differentiation of various causes of the disease. In this review, we present the pathophysiology and CT imaging features of non-atherosclerotic CAD.
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Objective@#To evaluate the feasibility of single-shot whole thoracic time-resolved MR angiography (TR-MRA) to identify the feeding arteries of pulmonary arteriovenous malformations (PAVMs) and reperfusion of the lesion after embolization in patients with multiple PAVMs. @*Materials and Methods@#Nine patients (8 females and 1 male; age range, 23–65 years) with a total of 62 PAVMs who underwent percutaneous embolization for multiple PAVMs and were subsequently followed up using TR-MRA and CT obtained within 6 months from each other were retrospectively reviewed. All imaging analyses were performed by two independent readers blinded to clinical information. The visibility of the feeding arteries on maximum intensity projection (MIP) reconstruction and multiplanar reconstruction (MPR) TR-MRA images was evaluated by comparing them to CT as a reference. The accuracy of TR-MRA for diagnosing reperfusion of the PAVM after embolization was assessed in a subgroup with angiographic confirmation. The reliability between the readers in interpreting the TR-MRA results was analyzed using kappa (κ) statistics. @*Results@#Feeding arteries were visible on the original MIP images of TR-MRA in 82.3% (51/62) and 85.5% (53/62) of readers 1 and 2, respectively. Using the MPR, the rates increased to 93.5% (58/62) and 95.2% (59/62), respectively (κ = 0.760 and 0.792, respectively). Factors for invisibility were the course of feeding arteries in the anteroposterior plane, proximity to large enhancing vessels, adjacency to the chest wall, pulsation of the heart, and small feeding arteries. Thirty-seven PAVMs in five patients had angiographic confirmation of reperfusion status after embolization (32 occlusions and 5 reperfusions).TR-MRA showed 100% (5/5) sensitivity and 100% (32/32, including three cases in which the feeding arteries were not visible on TR-MRA) specificity for both readers. @*Conclusion@#Single-shot whole thoracic TR-MRA with MPR showed good visibility of the feeding arteries of PAVMs and high accuracy in diagnosing reperfusion after embolization. Single-shot whole thoracic TR-MRA may be a feasible method for the follow-up of patients with multiple PAVMs.
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Unilateral pulmonary vein atresia (PVA) is a rare congenital cardiovascular anomaly occurring after the common pulmonary vein fails to incorporate into the left atrium. It is most commonly diagnosed in childhood, and diagnosis after reaching adulthood is extremely rare. Dyspnea on exertion and hemoptysis are common clinical features in adult PVA patients, whereas lung parenchymal abnormalities are indirect signs of PVA, which can manifest as interstitial lung disease. Herein, we present the case of a 62-year-old female diagnosed with unilateral PVA presenting as unilateral interstitial lung disease and report the changes in her chest radiographs over 12 years.
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Purpose@#Silent information regulator 1 (SIRT1) in the brain is essential for maintaining cellular homeostasis and plays a neuroprotective role in cerebral ischemia and neurodegenerative disorders. The effect of preischemic treadmill exercise on chronic cerebral hypoperfusion (CCH)-induced spatial learning memory impairment, microvascular injury, and blood-brain barrier (BBB) disruption in relation with SIRT1 expression was evaluated. @*Methods@#Prior to bilateral common carotid artery occlusion (BCCAO) surgery, the rats in the exercise groups performed low-intensity treadmill running for 30 minutes once daily during 8 weeks. BCCAO surgery was performed on male Wistar rats at 12 weeks of age. Spatial learning memory was measured using the Morris water maze test. Neuronal nuclear antigen, SIRT1, and rat endothelial cells antigen 1 were determined by immunohistochemistry and platelet-derived growth factor receptor beta was determined by immunofluorescence. @*Results@#Preischemic treadmill exercise ameliorated spatial learning memory impairment and enhanced SIRT1 expression in the BCCAO rats. Preischemic treadmill exercise ameliorated BCCAO-induced damage to microvasculature and pericytes that make up the BBB. The effect of preischemic treadmill exercise was lost with sirtinol treatment. @*Conclusions@#These results can apply treadmill exercise prior to cerebral ischemia as a rational preventive and therapeutic intervention strategy to improve cognitive dysfunction in CCH patients.
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Extracellular vesicles (EVs) are sub-micrometer lipid vesicles secreted from parental cells with their information such as DNA, RNA, and proteins. EVs can deliver their cargo to recipient cells and regulate the signaling pathway of the recipient cells to determine their destiny. Depending on the cargo of EVs, the recipient cells can be changed into abnormal state or be relieved from diseases. Therefore, EVs has been spotlighted as emerging therapeutics in biomedical research. However, slow EV secretion rate is the major limitation for the clinical applications of EVs. EV secretion is highly environmental dependent and can be regulated by various stimulants such as chemicals, oxygen levels, pH, radiation, starvation, and culture methods. To overcome the limitation of low productivity of EVs, EV stimulation methods have been widely studied and applied to massive EV productions. Another strategy is the synthesis of artificial EVs from cells by physical methods such as nitrogen cavitation, extrusion via porous membrane, and sonication. These physical methods disrupt cellular membrane and reassemble the membrane to lipid vesicles containing proteins or drugs. In this review, we will focus on how EV generation can be enhanced and recent advances in large scale EV generation strategies.
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Extracellular vesicles (EVs) are sub-micrometer lipid vesicles secreted from parental cells with their information such as DNA, RNA, and proteins. EVs can deliver their cargo to recipient cells and regulate the signaling pathway of the recipient cells to determine their destiny. Depending on the cargo of EVs, the recipient cells can be changed into abnormal state or be relieved from diseases. Therefore, EVs has been spotlighted as emerging therapeutics in biomedical research. However, slow EV secretion rate is the major limitation for the clinical applications of EVs. EV secretion is highly environmental dependent and can be regulated by various stimulants such as chemicals, oxygen levels, pH, radiation, starvation, and culture methods. To overcome the limitation of low productivity of EVs, EV stimulation methods have been widely studied and applied to massive EV productions. Another strategy is the synthesis of artificial EVs from cells by physical methods such as nitrogen cavitation, extrusion via porous membrane, and sonication. These physical methods disrupt cellular membrane and reassemble the membrane to lipid vesicles containing proteins or drugs. In this review, we will focus on how EV generation can be enhanced and recent advances in large scale EV generation strategies.
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Objective@#Lung segmentation using volumetric quantitative computed tomography (CT) analysis may help predict outcomes of patients with coronavirus disease (COVID-19). The aim of this study was to investigate the relationship between CT volumetric quantitative analysis and prognosis in patients with COVID-19. @*Materials and Methods@#CT images from patients diagnosed with COVID-19 from February 18 to April 15, 2020 were retrospectively analyzed. CT with a negative finding, failure of quantitative analysis, or poor image quality was excluded. CT volumetric quantitative analysis was performed by automated volumetric methods. Patients were stratified into two risk groups according to CURB-65: mild (score of 0–1) and severe (2–5) pneumonia. Outcomes were evaluated according to the critical event-free survival (CEFS). The critical events were defined as mechanical ventilator care, ICU admission, or death.Multivariable Cox proportional hazards analyses were used to evaluate the relationship between the variables and prognosis. @*Results@#Eighty-two patients (mean age, 63.1 ± 14.5 years; 42 females) were included. In the total cohort, male sex (hazard ratio [HR], 9.264; 95% confidence interval [CI], 2.021–42.457; p = 0.004), C-reactive protein (CRP) (HR, 1.080 per mg/dL;95% CI, 1.010–1.156; p = 0.025), and COVID-affected lung proportion (CALP) (HR, 1.067 per percentage; 95% CI, 1.033– 1.101;p < 0.001) were significantly associated with CEFS. CRP (HR, 1.164 per mg/dL; 95% CI, 1.006–1.347; p = 0.041) was independently associated with CEFS in the mild pneumonia group (n = 54). Normally aerated lung proportion (NALP) (HR, 0.872 per percentage; 95% CI, 0.794–0.957; p = 0.004) and NALP volume (NALPV) (HR, 1.002 per mL; 95% CI, 1.000–1.004;p = 0.019) were associated with a lower risk of critical events in the severe pneumonia group (n = 28). @*Conclusion@#CRP in the mild pneumonia group; NALP and NALPV in the severe pneumonia group; and sex, CRP, and CALP in the total cohort were independently associated with CEFS in patients with COVID-19.
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PURPOSE@#To evaluate the feasibility of comprehensive left ventricle (LV) functional parameters on routine coronary computed tomographic angiography (CCTA) based on two-dimensional echocardiography (2DE).@*MATERIALS AND METHODS@#Ninety-nine patients who underwent CCTA accompanied by 2DE were included in the study. The volumetric LV systolic functional parameters were acquired from 10-phase reconstruction of CCTA data. By differentiating the time-LV volume curve by time domain and measuring mitral valvular orifice areas, transmitral time-velocity curves were drawn and the early (E) to late (A) mitral inflow peak velocities ratio (E/A ratio) was acquired. By measuring a longitudinal jerking velocity of the mitral valvular annulus on a four-chamber view, the mitral peak velocity of early filling (E) to early diastolic mitral annular velocity (E') ratio (E/E' ratio) was evaluated. All functional parameters were compared with the 2DE results.@*RESULTS@#The LV end diastolic volume, LV end systolic volume, ejection fraction, stroke volume, cardiac output, and LV myocardial mass measured by CCTA and 2DE showed moderate to strong correlations (r = 0.732, 0.821, 0.416, 0.394, 0.328, and 0.764, respectively; p < 0.05). The E/A and E/E' ratios showed strong correlation between CCTA and echocardiography (r = 0.807 and 0.751, respectively; p < 0.05).@*CONCLUSION@#When CCTA is performed with retrospective electrocardiographic gating, additional information about the LV function can be acquired as reliably as with echocardiography.
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PURPOSE: This study was done to identify whether pre-conditioning exercise has neuroprotective effects against cerebral ischemia, through enhance brain microvascular integrity. METHODS: Adult male Sprague-Dawley rats were randomly divided into four groups: 1) Normal (n=10); 2) Exercise (n=10); 3) Middle cerebral artery occlusion (MCAo), n=10); 4) Exercise+MCAo (n=10). Both exercise groups ran on a treadmill at a speed of 15 m/min, 30 min/day for 4 weeks, then, MCAo was performed for 90 min. Brain infarction was measured by Nissl staining. Examination of the remaining neuronal cell after MCAo, and microvascular protein expression on the motor cortex, showed the expression of Neuronal Nuclei (NeuN), Vascular endothelial growth factor (VEGF) & laminin. RESULTS: After 48 hr of MCAo, the infarct volume was significantly reduced in the Ex+MCAo group (15.6+/-2.7%) compared to the MCAo group (44.9+/-3.8%) (p<.05), and many neuronal cells were detected in the Ex+MCAo group (70.8+/-3.9%) compared to the MCAo group (43.4+/-5.1%) (p<.05). The immunoreactivity of laminin, as a marker of microvessels and Vascular endothelial growth factor (VEGF) were intensively increased in the Ex+MCAo group compared to the MCAo group. CONCLUSION: These findings suggest that the neuroprotective effects of exercise pre-conditioning reduce ischemic brain injury through strengthening the microvascular integrity after cerebral ischemia.