Transthoracic echocardiographic Doppler metrics in evaluating bioprosthetic tricuspid valve dysfunction.

PURPOSE: There is currently limited information on the utility of transthoracic echocardiography (TTE)-derived Doppler parameters for assessing bioprosthetic tricuspid valve (BTV) dysfunction. Our study aimed to establish the precision and appropriate reference ranges for routinely collected transthoracic Doppler parameters in the assessment of BTV dysfunction. METHODS: We retrospectively evaluated 100 BTV patients who underwent TTE. Based on redo surgical confirmation or more than 2 repeat TTE or transesophageal echocardiography (TEE) examinations, patients were allocated to normal (n = 61), regurgitant (n = 24), or stenotic (n = 15) BTV group. Univariate and multivariate binary logistic regression were performed to identify TTE Doppler parameters that detected BTV dysfunction. RESULTS: The VTI ratio (VTITV/VTILVOT) was the most accurate Doppler parameter for detecting BTV dysfunction, with a ratio of >2.8 showing 84.6% sensitivity and 90.2% specificity. VTI ratio > 3.2, mean gradient (MGTV) > 6.2 mmHg and pressure half-time > 218 ms detected significant BTV stenosis, with sensitivities of 100%, 93.3% and 93.3% and specificities of 82.4%, 75.3% and 87.1%, respectively. After multivariate analysis, the VTI ratio > 2.8 (OR = 9.00, 95% CI = 2.13-41.61, p = .003) and MGTV > 5.1 mmHg (OR = 6.50, 95% CI = 1.69-27.78, p = .008) were the independent associations of BTV dysfunction. With these cutoff values, 75.0%-92.2% of normal and 62.5%-96.0% of dysfunctional BTV were identified. CONCLUSIONS: Doppler parameters from TTE can accurately identify BTV dysfunction, particularly with VTI ratio > 2.8 and MGTV > 5.1 mmHg, to assess the need for additional testing with TEE.

Synthesis of Pyrazolo[1,5-a]pyridinyl, Pyrazolo[1,5-a]quinolinyl, and Pyrazolo[5,1-a]isoquinolinyl Sulfonyl Fluorides via a [3 + 2] Annulation.

A [3 + 2] cycloaddition reaction of N-aminopyridines, N-aminoquinolines, and N-aminoisoquinolines with 1-bromoethene-1-sulfonyl fluoride (BESF) was performed to obtain optimum yields of various useful pyrazolo[1,5-a]pyridinyl, pyrazolo[1,5-a]quinolinyl, and pyrazolo[5,1-a]isoquinolinyl sulfonyl fluorides (43-90% yield). The transformation process showed broad substrate specificity, mild reaction conditions, and operational simplicity. Therefore, the reaction has great applicable value in the field of medicinal chemistry and other disciplines.

Echocardiography of a left ventricular apical thrombus after myocardial infarction: A complementary role of the linear transducer array.

We presented a 28-year-old man with myocardial infarction with an apical mass detected by echocardiography. Compared with routine imaging using a phased transducer array, linear transducer arrays were used in two-dimensional and contrast echocardiography to enhance apical visualization and successfully demonstrated the shape and blood perfusion of apical thrombus with precision. We successfully explored the feasibility of imaging the apical thrombus with a linear transducer array.

Intracardiac masses in a giant right atrium: Tumors or thrombus?

The coexist of primary angiosarcoma and thrombosis is a rare clinical entity. A 46-year-old male was presented with multiple right atrial (RA) masses. Two different vascular patterns in these masses were identified by contrast echocardiography. The possibility of coexistence of malignant tumors and thrombus in RA was implicated, which was further confirmed by computed tomography, magnetic resonance imaging, positron emission tomography/computer tomography, and pathologic examination. This case highlights the advantages of contrast echocardiography in the differential diagnosis of cardiac masses.

Euxanthone improves cognitive impairment by attenuating mitochondrial fragmentation and suppressing oxidative stress.

Mitophagy and apoptosis significantly contribute to the dynamics of mitochondria and their associated disorders. Euxanthone (EUX) is a xanthone derivative that exhibits several therapeutic effects at a preclinical level. However, its impact in a cerebral ischemia and reperfusion model has not been investigated. The investigation aimed to determine the protective effect of EUX in cerebral ischemia and cognitive impairment and explore its underlying mechanism. A bilateral common carotid artery occlusion (BCCAO) model was employed in the present work. Forty male ICR mice were divided into four groups - Sham, BCCAO, EUX30 (BCCAO + EUX 30 mg/kg) and EUX60 (BCCAO + EUX 60 mg/kg). The mice were then subjected to a Morris water maze study for investigation of learning and memorizing capabilities. The hippocampal specimens of mice were quantified for the presence of oxidative markers. Homogenized hippocampal fractions were determined for the levels of Beclin-1, LC3, p53, Bax, caspase-3, Bnip3, DRP1 and Nrf2. The present investigation revealed that BCCAO caused oxidative stress in mitochondria and led to mitochondrial breakdown. EUX administration markedly attenuated BCCAO triggered mitochondrial stress and related breakdown. EUX treatment normalized Bnip3, Beclin1, Pink1, Parkin, p53, Bax, caspase-3, and LC3 II/I. Altogether, EUX treatment modulated mitophagy and apoptosis induced by mitochondrial stress mediated by mitochondrial fragmentation, due to cerebral ischemia and reperfusion injury.

Multimodality imaging in preparation for resection of a right atrial cavernous hemangioma.

A cardiac cavernous hemangioma is an extremely rare primary benign cardiac tumor. Herein, we report a case of cavernous hemangioma in the right atrium and close to the coronary sinus of an asymptomatic 56-year-old male who underwent multimodality imaging and successful resection of the cavernous hemangioma. Our case highlights that multimodality imaging plays an important role in characterizing cardiac hemangiomas and determining the surgical plan.

Multimodality imaging in preparation for surgery of coronary to pulmonary arterial fistulas complicated with a huge coronary aneurysm.

Coronary to pulmonary arterial fistula complicated with huge coronary aneurysm is a very rare condition. In this paper, we report a patient with bilateral coronary arteries to pulmonary artery fistulas with a giant coronary artery aneurysm. The patient was treated successfully by closure of the fistulas and repair of the coronary artery aneurysm with the preparation of multimodality imaging for surgery.

Protective role of glucocorticosteroid prior to endotoxin exposure in cultured neonatal type II alveolar epithelial cells.

BACKGROUND: Dexamethasone (DEX) is widely used for antenatal lung maturation and has been investigated to prevent premature lung injury by inhibiting postnatal inflammation. Its pharmacological mechanisms in the treatment of bacterial infection-induced injury of neonatal lung parenchymal cells remain to be clarified. We hypothesized that DEX pretreatment may attenuate endotoxin-induced growth suppression and regulate cytokine mRNA expression in cultured neonatal type II alveolar epithelial cells (AEC-II). METHODS: AEC-II of newborn piglets were freshly isolated and cultured. After pretreatment of 0.01, 0.1, 1.0 and 10 µmol/l DEX (E0.01, E0.1, E1.0 and E10 group, respectively) for 24 h, the cells were cultured with 1 µg/ml lipopolysaccharides (LPS) for 7 days with medium replacement every 24 h. Messenger RNA expression of surfactant proteins (SPs), pro-inflammatory cytokines and multiple growth factors (GF) were determined by RT-PCR, along with the cell growth and apoptosis measurements. RESULTS: LPS without DEX pretreatment suppressed cell proliferation, enhanced expression of pro-inflammatory cytokine mRNA and apoptosis, which was ameliorated in all DEX-pretreated groups on day 3. On day 3 and 5, only cells pretreated by E1.0 and E10 showed a 20-fold increase in insulin-like GF-1 mRNA expression whereas the expression of other GFs was down-regulated. LPS exposure reduced the expression of SP-A, B, C and Aquaporin-5 mRNA on day 3-7. However, the expression of SP-C mRNA was increased in E1.0 on day 3, which was supported by in situ expression of pro-SP-C with immunocytochemical assay. CONCLUSION: LPS-induced in vitro AEC-II injury was partially prevented by DEX pretreatment, with 1.0 µmol/l being the potentially optimal concentration. (253 words).

Regulation of microglial activation in stroke.

When ischemic stroke occurs, oxygen and energy depletion triggers a cascade of events, including inflammatory responses, glutamate excitotoxicity, oxidative stress, and apoptosis that result in a profound brain injury. The inflammatory response contributes to secondary neuronal damage, which exerts a substantial impact on both acute ischemic injury and the chronic recovery of the brain function. Microglia are the resident immune cells in the brain that constantly monitor brain microenvironment under normal conditions. Once ischemia occurs, microglia are activated to produce both detrimental and neuroprotective mediators, and the balance of the two counteracting mediators determines the fate of injured neurons. The activation of microglia is defined as either classic (M1) or alternative (M2): M1 microglia secrete pro-inflammatory cytokines (TNFα, IL-23, IL-1ß, IL-12, etc) and exacerbate neuronal injury, whereas the M2 phenotype promotes anti-inflammatory responses that are reparative. It has important translational value to regulate M1/M2 microglial activation to minimize the detrimental effects and/or maximize the protective role. Here, we discuss various regulators of microglia/macrophage activation and the interaction between microglia and neurons in the context of ischemic stroke.

Age-related differences in interferon regulatory factor-4 and -5 signaling in ischemic brains of mice.

Stroke is a disease that mainly affects the elderly. Since the age-related differences in stroke have not been well studied, modeling stroke in aged animals is clinically more relevant. The inflammatory responses to stroke are a fundamental pathological procedure, in which microglial activation plays an important role. Interferon regulatory factor-5 (IRF5) and IRF4 regulate M1 and M2 activation of macrophages, respectively, in peripheral inflammation; but it is unknown whether IRF5/IRF4 are also involved in cerebral inflammatory responses to stroke and whether age-related differences of the IRF5/IRF4 signaling exist in ischemic brain. Here, we investigated the influences of aging on IRF5/IRF4 signaling and post-stroke inflammation in mice. Both young (9-12 weeks) and aged (18 months) male mice were subjected to middle cerebral artery occlusion (MCAO). Morphological and biochemical changes in the ischemic brains and behavior deficits were assessed on 1, 3, and 7 d post-stroke. After MCAO, the aged mice showed smaller infarct sizes but higher neurological deficits and corner test scores than young mice. Young mice had higher levels of IRF4 and CD206 microglia in the ischemic brains, whereas the aged mice expressed more IRF5 and MHCII microglia. After MCAO, serum pro-inflammatory cytokines (TNF-α, iNOS, IL-6) were more prominently up-regulated in aged mice, whereas serum anti-inflammatory cytokines (TGF-ß, IL-4, IL-10) were more prominently up-regulated in young mice. Our results demonstrate that aging has a significant influence on stroke outcomes in mice, which is probably mediated by age-specific inflammatory responses.

Progress in extracellular vesicle homeostasis as it relates to cardiovascular diseases.

Extracellular vesicles (EVs) are involved in both physiological and pathological processes in many organ systems and are essential in mediating intercellular communication and maintaining organismal homeostasis. It is helpful to propose new strategies for disease treatment by elucidating the mechanisms of EV release and sorting. An increasing number of studies have shown that there is specific homeostasis in EVs, which is helpful for the human body to carry out physiological activities. In contrast, an EV homeostasis im-balance promotes or accelerates disease onset and development. Alternatively, regulating the quality of EVs can maintain homeostasis and even achieve the purpose of treating conditions. An analysis of the role of EV homeostasis in the onset and development of cardiovascular disease is presented in this review. This article also summarizes the methods that regulate EV homeostasis and their application in cardiovascular diseases. In particular, this study focuses on the connection between EV steady states and the cardiovascular system and the potential value of EVs in treating cardiovascular diseases.

Multidirectional myocardial function in bicuspid aortic valve stenosis patients: a three-dimensional speckle tracking analysis.

Purpose: The impact of aortic stenosis (AS) severity on multidirectional myocardial function in patients with bicuspid aortic valve (BAV) remains unclear, despite the recognized presence of early left ventricular longitudinal myocardial dysfunction in BAV patients with normal valve function. The aim of the study was to evaluate the multidirectional myocardial functions of BAV patients. Methods: A total of 86 BAV patients (age 46.71 ± 13.62 years, 69.4% men) with normally functioning (BAV-nf), mild AS, moderate AS, and severe AS with preserved left ventricular ejection fraction (LVEF ≥ 52%) were included. 30 healthy volunteers were recruited as the control group. Multidirectional strain and volume analysis were performed by three-dimensional speckle tracking echocardiography(3D-STE). Results: Global longitudinal strain (GLS), and global radial strain (GRS) were reduced in BAV-nf patients compared with the controls. With each categorical of AS severity from BAV-nf to severe AS, there was an associated progressive impairment of GLS and GRS (all P < 0.001). Global circumferential strain (GCS) did not show a significant decrease from BAV-nf to mild AS but began to decrease from moderate AS. Multiple linear regressions indicated that indexed aortic valve area (AVA/BSA), as a measure of AS severity, was an independent determinant of GLS, GCS and GRS. Conclusions: Left ventricular longitudinal myocardial reduction is observed even in patients with well-functioning bicuspid aortic valves. With each categorical increase in the grade of AS severity from normally functioning to severe aortic stenosis, there was an associated progressive impairment of longitudinal myocardial function. Furthermore, circumferential myocardial function was starting damaged from moderate AS. AVA/BSA was independently associated with multidirectional myocardial function injuries.

Risk factors for the recurrence of left atrioventricular valvular regurgitation after surgical repair of partial and transitional atrioventricular septal defect.

Background: Left atrioventricular valvular regurgitation (LAVVR) recurrence after partial and transitional atrioventricular septal defect (AVSD) repair is the main risk factor associated with reoperation or mortality. The purpose of this study was to identify risk factors associated with the recurrence of LAVVR after surgical repair of transitional and partial AVSD at a single institution. Methods: A hundred and fifty-seven patients who underwent anatomical repair for partial and transitional AVSD from January 2013 to December 2021 were included in our institutional database. Demographic characteristics, operative information, comorbidities, complications, and outcomes were retrieved from electronic medical records. Echocardiographic evaluations included cardiac dimensions, the degree of LAVVR, and the anatomy of the atrioventricular valve. Results: After a median follow-up period of 5.8 years, 40 patients had recurrent moderate or even more severe LAVVR. Compared with patients without recurrent LAVVR, those experiencing LAVVR recurrence were more likely to have larger preoperative left atrial (LA) size and larger left ventricular (LV) size after standardization, larger left atrioventricular valve (LAVV) cleft width, higher proportions of preoperative moderate or even more severe LAVVR, and immediately postoperative mild to moderate or even more severe LAVVR. Univariate Cox regression analysis showed that age at first repair, height, LA size after standardization, LV size after standardization, the severity of preoperative LAVVR, immediately postoperative LAVVR, and the LAVV cleft width more than 1cm were risk factors for recurrent LAVVR (P<0.05 for all). Multivariable Cox regression analysis showed that mild to moderate or even more severe LAVVR postoperatively [hazard ratio (HR) 9.53, 95% confidence interval (CI): 3.78-24.01; P<0.001], the width of LAVV cleft more than 1 cm (HR: 3.90, 95% CI: 1.80-8.48; P<0.001) and age at first repair (HR: 0.45, 95% CI: 0.31-0.66; P<0.001) were independently associated with the recurrence of LAVVR. Conclusions: The width of LAVV cleft, mild to moderate or even more severe LAVVR immediately after surgery, and age at initial surgery are risk factors for recurrent LAVVR. The presence of recurrent LAVVR necessitates proactive surveillance to facilitate timely reintervention.

A Membrane-Targeting Aggregation-Induced Emission Probe for Monitoring Lipid Droplet Dynamics in Ischemia/Reperfusion-Induced Cardiomyocyte Ferroptosis.

Myocardial ischemia/reperfusion injury (MIRI) is the leading cause of irreversible myocardial damage. A pivotal pathogenic factor is ischemia/reperfusion (I/R)-induced cardiomyocyte ferroptosis, marked by iron overload and lipid peroxidation. However, the impact of lipid droplet (LD) changes on I/R-induced cardiomyocyte ferroptosis is unclear. In this study, an aggregation-induced emission probe, TPABTBP is developed that is used for imaging dynamic changes in LD during myocardial I/R-induced ferroptosis. TPABTBP exhibits excellent LD-specificity, superior capability for monitoring lipophagy, and remarkable photostability. Molecular dynamics (MD) simulation and super-resolution fluorescence imaging demonstrate that the TPABTBP is specifically localized to the phospholipid monolayer membrane of LDs. Imaging LDs in cardiomyocytes and myocardial tissue in model mice with MIRI reveals that the LD accumulation level increase in the early reperfusion stage (0-9 h) but decrease in the late reperfusion stage (>24 h) via lipophagy. The inhibition of LD breakdown significantly reduces the lipid peroxidation level in cardiomyocytes. Furthermore, it is demonstrated that chloroquine (CQ), an FDA-approved autophagy modulator, can inhibit ferroptosis, thereby attenuating MIRI in mice. This study describes the dynamic changes in LD during myocardial ischemia injury and suggests a potential therapeutic target for early MIRI intervention.

Platelet membrane-derived biomimetic microbubbles with enhanced targeting ability for the early detection of myocardial ischemia-reperfusion injury.

Myocardial ischemia-reperfusion injury (MIRI) is a widely recognized cardiovascular disease that significantly impacts the prognosis of patients undergoing myocardial infarction recanalization. This condition can be fatal and involves complex pathophysiological mechanisms. Early diagnosis of MIRI is crucial to minimize myocardial damage and reducing mortality. Based on the inherent relationship between platelets and MIRI, we developed biomimetic microbubbles coated with platelet membrane (MB-pla) for early identification of MIRI. The MB-pla were prepared through a recombination process involving platelet membrane obtained from rat whole blood and phospholipids, blended in appropriate proportions. By coating the microbubbles with platelet membrane, MB-pla acquired various adhesion molecules, thereby gaining the capability to selectively adhere to damaged endothelial cells in the context of MIRI. In vitro experiments demonstrated that MB-pla exhibited remarkable targeting characteristics, particularly toward type IV collagen and human umbilical vein endothelial cells that had been injured through hypoxia/reoxygenation procedures. In a rat model of MIRI, the signal intensity produced by MB-pla was notably higher than that of control microbubbles. These findings were consistent with results obtained from fluorescence imaging of isolated hearts and immunofluorescence staining of tissue sections. In conclusion, MB-pla has great potential as a non-invasive early detection method for MIRI. Furthermore, this approach can potentially find application in other conditions involving endothelial injury in the future.

In-Situ TEM Investigation of Helium Implantation in Ni-SiOC Nanocomposites.

Ni-SiOC nanocomposites maintain crystal-amorphous dual-phase nanostructures after high-temperature annealing at different temperatures (600 °C, 800 °C and 1000 °C), while the feature sizes of crystal Ni and amorphous SiOC increase with the annealing temperature. Corresponding to the dual-phase nanostructures, Ni-SiOC nanocomposites exhibit a high strength and good plastic flow stability. In this study, we conducted a He implantation in Ni-SiOC nanocomposites at 300 °C by in-situ transmission electron microscope (TEM) irradiation test. In-situ TEM irradiation revealed that both crystal Ni and amorphous SiOC maintain stability under He irradiation. The 600 °C annealed sample presents a better He irradiation resistance, as manifested by a smaller He-bubble size and lower density. Both the grain boundary and crystal-amorphous phase boundary act as a sink to absorb He and irradiation-induced defects in the Ni matrix. More importantly, amorphous SiOC ceramic is immune to He irradiation damage, contributing to the He irradiation resistance of Ni alloy.

A Deep Learning Model for Diagnosing COVID-19 and Pneumonia through X-ray.

BACKGROUND: The new global pandemic caused by the 2019 novel coronavirus (COVID-19), novel coronavirus pneumonia, has spread rapidly around the world, causing enormous damage to daily life, public health security, and the global economy. Early detection and treatment of COVID-19 infected patients are critical to prevent the further spread of the epidemic. However, existing detection methods are unable to rapidly detect COVID-19 patients, so infected individuals are not detected in a timely manner, which complicates the prevention and control of COVID-19 to some extent. Therefore, it is crucial to develop a rapid and practical COVID-19 detection method. In this work, we explored the application of deep learning in COVID-19 detection to develop a rapid COVID-19 detection method. METHODS: Existing studies have shown that novel coronavirus pneumonia has significant radiographic performance. In this study, we analyze and select the features of chest radiographs. We propose a chest X-Ray (CXR) classification method based on the selected features and investigate the application of transfer learning in detecting pneumonia and COVID-19. Furthermore, we combine the proposed CXR classification method based on selected features with transfer learning and ensemble learning and propose an ensemble deep learning model based on transfer learning called COVID-ensemble to diagnose pneumonia and COVID-19 using chest x-ray images. The model aims to provide an accurate diagnosis for binary classification (no finding/pneumonia) and multivariate classification (COVID-19/No findings/ Pneumonia). RESULTS: Our proposed CXR classification method based on selection features can significantly improve the CXR classification accuracy of the CNN model. Using this method, DarkNet19 improved its binary and triple classification accuracies by 3.5% and 5.78%, respectively. In addition, the COVIDensemble achieved 91.5% accuracy in the binary classification task and 91.11% in the multi-category classification task. The experimental results demonstrate that the COVID-ensemble can quickly and accurately detect COVID-19 and pneumonia automatically through X-ray images and that the performance of this model is superior to that of several existing methods. CONCLUSION: Our proposed COVID-ensemble can not only overcome the limitations of the conventional COVID-19 detection method RT-PCR and provide convenient and fast COVID-19 detection but also automatically detect pneumonia, thereby reducing the pressure on the medical staff. Using deep learning models to automatically diagnose COVID-19 and pneumonia from X-ray images can serve as a fast and efficient screening method for COVID-19 and pneumonia.

Advances in metabolomics of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a chronic lung disease with limited airflow. COPD is characterized by chronic bronchitis and emphysema, and is often accompanied by malnutrition with fatigue, muscle weakness, and an increased risk of infection. Although the pulmonary function test is used as the gold criterion for diagnosing COPD, it is unable to identify early COPD or classify the subtypes, thereby impeding early intervention and the precise diagnosis of COPD. Recent evidence suggests that metabolic dysfunction, such as changes in lipids, amino acids, glucose, nucleotides, and microbial metabolites in the lungs and intestine, have a great potential for diagnosing COPD in the early stage. However, a comprehensive summary of these metabolites and their effects on COPD is still lacking. This review summarizes the metabolites that are changed in COPD and highlights some promising early diagnostic markers and therapeutic targets. We emphasize that intensified dietary management may be among the most feasible methods to improve metabolism in the body.