Solid splenic lymphangioma: Unveiling an atypical presentation in lymphatic system malformations.

We present a case study detailing the occurrence of splenic lymphangioma in a 9-year-old girl. The multimodal imaging revealed a significant mass, a finding subsequently validated through histopathological examination. This case underscores the importance of considering splenic lymphangioma as a rare but notable differential diagnosis for solid masses observed in imaging studies.

Intra-Zero-Energy Landau Level Crossings in Bilayer Graphene at High Electric Fields.

The highly tunable band structure of the zero-energy Landau level (zLL) of bilayer graphene makes it an ideal platform for engineering novel quantum states. However, the zero-energy Landau level at high electric fields has remained largely unexplored. Here we present magnetotransport measurements of bilayer graphene in high transverse electric fields. We observe previously undetected Landau level crossings at filling factors ν = -2, 1, and 3 at high electric fields. These crossings provide constraints for theoretical models of the zero-energy Landau level and show that the orbital, valley, and spin character of the quantum Hall states at high electric fields is very different from low electric fields. At high E, new transitions between states at ν = -2 with different orbital and spin polarization can be controlled by the gate bias, while the transitions between ν = 0 → 1 and ν = 2 → 3 show anomalous behavior.

Spin-Momentum Locking Induced Anisotropic Magnetoresistance in Monolayer WTe2.

Monolayer WTe2 is predicted to be a quantum spin Hall insulator (QSHI), and its quantized edge transport has recently been demonstrated. However, one of the essential properties of a QSHI, spin-momentum locking of the helical edge states, has yet to be experimentally validated. Here, we measure and observe gate-controlled anisotropic magnetoresistance (AMR) in monolayer WTe2 devices. Electrically tuning the Fermi energy into the band gap, a large in-plane AMR is observed and the minimum of the in-plane AMR occurs when the applied magnetic field is perpendicular to the current direction. In line with the experimental observations, the theoretical predictions based on the band structure of monolayer WTe2 demonstrate that the AMR effect originates from spin-momentum locking in the helical edge states of monolayer WTe2. Our findings reveal that the spin quantization axis of the helical edge states in monolayer WTe2 can be precisely determined from AMR measurements.

MicroRNA-23a-5p promotes atherosclerotic plaque progression and vulnerability by repressing ATP-binding cassette transporter A1/G1 in macrophages.

Disruption of carotid vulnerable atherosclerotic plaque is responsible for acute ischemic stroke (AIS) and the early detection and intervention approach are greatly limited. Undertaking a microarray of microRNAs (miRNAs) in the plasma of AIS patients with carotid vulnerable plaques, miR-23a-5p was markedly elevated and was positively correlated with the plaque progression and vulnerability. Correspondingly, we found that miR-23a-5p expression was significantly increased in both plasma and macrophages from atherosclerosis mice. Bioinformatics analysis and in vitro knockdown experiments identified that ATP-binding cassette transporter A1/G1 as a novel target of miR-23a-5p. Luciferase reporter assays showed that miR-23a-5p repressed the 3' untranslated regions (UTR) activity of ABCA1/G1. Moreover, functional analyses demonstrated that transfection of miR-23a-5p inhibitor enhanced cholesterol efflux and decreased foam cell formation through upregulating ABCA1/G1 expression levels. Furthermore, long term in vivo systemically delivered miR-23a-5p antagomir significantly increased ABCA1/G1 expression in the aorta of ApoE-/- mice. Importantly, the miR-23a-5p antagomir therapy significantly reduced atherosclerosis progression and promoted plaque stability. Our observations indicate that miR-23a-5p promotes macrophage-derived foam cell formation and might be a key regulator contributing to atherosclerotic plaque progression and vulnerability.

Asiatic acid enhances survival of human AC16 cardiomyocytes under hypoxia by upregulating miR-1290.

Asiatic acid (AA) could attenuate ischemia/reperfusion induced myocardial apoptosis through upregulating the Akt/GSK-3ß/HIF-1α pathway. HIF-3α is a negative regulator of HIF-1α, whose mRNA is a potential target of miR-1290. AA could upregulate miR-1290 in non-small-cell lung cancer A549 cells. This work aimed to investigate whether AA could inhibit hypoxia induced cardiomyocyte apoptosis through regulating the miR-1290/HIF3A/HIF-1α axis. The AC16 human myocardial cell line cultured under normoxic or hypoxic conditions was treated with various doses of AA for 24 h. Afterwards cell viability, apoptosis and the expression of miR-1290, HIF3A, and HIF1A were evaluated. Cells transfected with miR-1290 mimic or inhibitor were used to determine the role of miR-1290 in the anti-apoptosis effect of AA and the expression of HIF3A and HIF1A. Dual luciferase assay was performed to confirm miR-1290 targeting of HIF3A. HIF3A overexpression was achieved by transfection of HIF3A1 overexpressing lentivirus, and its effect on miR-1290 and AA-regulated survival of cardiomyocytes was evaluated. AA treatment protected cardiomyocytes from hypoxia-induced apoptosis and upregulated miR-1290 and HIF1A, but downregulated HIF3A under hypoxia. The protective effect of AA was abolished by miR-1290 knockdown, whereas enhanced by miR-1290 overexpression. In addition, miR-1290 knockdown increased HIF1A expression, but reduced HIF3A expression in cardiomyocytes. Dual luciferase assay confirmed miR-1290 direct targeting the 3' UTR of HIF3A. HIF3A overexpression counteracted the anti-apoptosis effect of AA or miR-1290. In conclusion, AA can protect cardiomyocytes against hypoxia-induced apoptosis through regulating the miR-1290/HIF3A/HIF-1α axis, and miR-1290 may be a potential target in the prevention of myocardial ischemia-reperfusion injury. © 2017 IUBMB Life, 69(9):660-667, 2017.

MicroRNA-148a promotes apoptosis and suppresses growth of breast cancer cells by targeting B-cell lymphoma 2.

MicroRNAs (miRNAs) contribute toward tumorigenesis through the modulation of tumor-related genes. MiR-148a has been characterized as a tumor-suppressing miRNA and its downregulation has been reported in tumors of a variety of cancers. However, the functional role of miR-148a in breast cancer is not yet fully understood. Using both in-vitro and in-vivo models, we confirmed that miR-148a acts to inhibit the proliferation of breast cancer cells. Through the use of bioinformatic approaches in miRNA target prediction, we determined that B-cell lymphoma 2 (BCL-2) is a likely target of miR-148a. The overexpression and tumorigenic effects of BCL-2 have already been confirmed in cancerous tumors of the breast. A dual-luciferase assay was performed to confirm that miR-148a targets the 3'-untranslated region of BCL-2. In this study, we first characterized the downregulation of miR-148a in breast cancer tissues. We then found that restoring expression of miR-148a suppressed the expression of BCL-2 at the level of both mRNA and protein. Upregulation of miR-148a caused a subsequent reduction of proliferation and an increase in apoptosis. In conclusion, we have confirmed the role of miR-148a as a pivotal regulator in breast cancer through its targeting of BCL-2. This evidence strongly suggests that miR-148a could prove to be a novel therapeutic target in breast cancer.

Defect introduced paramagnetism and weak localization in two-dimensional metal VSe2.

We have carried out a detailed investigation of the magnetism, valence state, and magnetotransport in VSe2 bulk single crystals, as well as in laminates obtained by mechanical exfoliation. In sharp contrast to the ferromagnetic behavior reported previously, here, no ferromagnetism could be detected for VSe2 single crystal and laminate from room temperature down to 2 K. Neither did we find the Curie paramagnetism expected due to the 3d 1 odd-electronic configuration of covalent V4+ ions. Rather, intrinsic VSe2 is a non-magnetic alloy without local moment. Only a weak paramagnetic contribution introduced by defects is noticeable below 50 K. A weak localization effect due to defects was also observed in VSe2 single crystals for the first time.

Structural Determinant and Its Underlying Molecular Mechanism of STPC2 Related to Anti-Angiogenic Activity.

In this study, we aimed to use different strategies to further uncover the anti-angiogenic molecular mechanism of a fucoidan-like polysaccharide STPC2, isolated from brown alga Sargassum thunbergii. A desulfated derivative, STPC2-DeS, was successfully prepared and identified. The native polysaccharide and desulfated product were subjected to evaluate their anti-angiogenic effects. In the tube formation assay, STPC2 showed dose-dependent inhibition. In addition, STPC2 could distinctly inhibit the permeation of HUVEC cells into the lower chamber. Moreover, a significant reduction of microvessel density was observed in chick chorioallantoic membrane assay treated with STPC2. Meanwhile, STPC2 was found to repress the VEGF-induced neovessel formation in the matrigel plug assay in vivo. However, STPC2-DeS failed to suppress the anti-angiogenic activity via these in vitro and in vivo strategies. In addition, we demonstrated that STPC2 could significantly downregulate the phosphorylation of VEGFR2 and its related downstream Src family kinase, focal adhesion kinase, and AKT kinase. Furthermore, surface plasmon resonance assay revealed that STPC2 bound strongly to VEGF to interfere with VEGF-VEGFR2 interaction. Taken together, these results evidently demonstrated that STPC2 exhibited a potent anti-angiogenic activity through binding to VEGF via sulfated groups to impede VEGF-VEGFR2 interaction, thus affected the downstream signaling molecules.

Are cancer stem cells the sole source of tumor?

Tumors are believed to consist of a heterogeneous population of tumor cells originating from rare cancer stem cells (CSCs). However, emerging evidence suggests that tumor may also originate from non-CSCs. To support this viewpoint, we are here to present definitive evidence indicating that the number of tumorigenic tumor cells is greater than that of CSCs in tumor, and tumor can also derive from non-CSCs. To achieve this, an idealized mathematical model was employed in the present study and theoretical calculation revealed that non-CSCs could initiate the occurrence of tumor if their proliferation potential was adequate. Further, experimental studies demonstrated that 17.7%, 38.6% and 5.2% of tumor cells in murine B16 solid melanoma, H22 hepatoma and Lewis lung carcinoma, respectively, were potentially tumorigenic. Thus, based on the aforementioned findings, we propose that the scarce CSCs, if exist, are not the sole source of a tumor.

Modality alignment contrastive learning for severity assessment of COVID-19 from lung ultrasound and clinical information.

The outbreak of COVID-19 around the world has caused great pressure to the health care system, and many efforts have been devoted to artificial intelligence (AI)-based analysis of CT and chest X-ray images to help alleviate the shortage of radiologists and improve the diagnosis efficiency. However, only a few works focus on AI-based lung ultrasound (LUS) analysis in spite of its significant role in COVID-19. In this work, we aim to propose a novel method for severity assessment of COVID-19 patients from LUS and clinical information. Great challenges exist regarding the heterogeneous data, multi-modality information, and highly nonlinear mapping. To overcome these challenges, we first propose a dual-level supervised multiple instance learning module (DSA-MIL) to effectively combine the zone-level representations into patient-level representations. Then a novel modality alignment contrastive learning module (MA-CLR) is presented to combine representations of the two modalities, LUS and clinical information, by matching the two spaces while keeping the discriminative features. To train the nonlinear mapping, a staged representation transfer (SRT) strategy is introduced to maximumly leverage the semantic and discriminative information from the training data. We trained the model with LUS data of 233 patients, and validated it with 80 patients. Our method can effectively combine the two modalities and achieve accuracy of 75.0% for 4-level patient severity assessment, and 87.5% for the binary severe/non-severe identification. Besides, our method also provides interpretation of the severity assessment by grading each of the lung zone (with accuracy of 85.28%) and identifying the pathological patterns of each lung zone. Our method has a great potential in real clinical practice for COVID-19 patients, especially for pregnant women and children, in aspects of progress monitoring, prognosis stratification, and patient management.

Wave intensity analysis of carotid artery: a noninvasive technique for assessing hemodynamic changes of hyperthyroid patients.

This study examined the wave intensity (WI) of the carotid artery in patients with hyperthyroid in order to assess the hemodynamic changes of hyperthyroid patients. A total of 86 hyperthyroid patients without cardiac morphological changes and arrhythmia, and 80 healthy control subjects were enrolled in the study. Right common carotid artery (RCCA) was selected for ultrasonic imaging to obtain WI indices, including amplitude of the peak during early systole (W1), amplitude of the peak during late systole (W2), area of the negative wave during mid-systole (NA), interval between R wave of electrocardiogram and W1 (R-1st), interval between W1 and W2 (1st-2nd). The levels of serum thyroid hormones, consisting of free triiodothyronine (FT3), free thyroxin (FT4) and thyroid stimulating hormone (TSH), were measured in hyperthyroid patients. Echocardiographic indices including left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were determined in each subject. The results showed that the W1, W2, NA, and (1st-2nd×HR) in hyperthyroid patients were significantly higher than those in healthy controls. There was no significant difference in LVEF and LVFS between the two groups. FT3 was correlated with W1, W2, NA, (1st-2nd×HR), pulse pressure (PP) and heart rate (HR) in hyperthyroid patients. Several abnormal waves on WI curves were present in 19 hyperthyroid patients during mid-systole. It was concluded that WI technique may prove a real-time, noninvasive, sensitive and convenient tool for assessing the cardiac function and hemodynamic alterations in hyperthyroid patients.

The protective role of carnosic acid in ischemic/reperfusion injury through regulation of autophagy under T2DM.

IMPACT STATEMENT: We have provided, for the first time, evidence that carnosic acid (CA) attenuates ischemia-reperfusion injury of diabetic myocardium, i.e. diabetic myocardial ischemia/reperfusion (DMI/R) injury, via enhancement of autophagy. A greater understanding of the target molecule in CA-enhanced autophagy is necessary for the development of potential chemotherapy for DMI/R injury.

Predictive Value of Duplex Ultrasound for Significant In-Stent Restenosis after Percutaneous Transluminal Renal Artery Stent Placement: A Propensity Score Matching Analysis.

To evaluate the value of pre-stenting and early post-stenting (<1 mo) duplex ultrasound parameters in predicting significant in-stent restenosis (ISR), we matched significant ISR patients 1:1 with controls without ISR in pre-stenting and early post-stenting (<1 mo) periods, respectively, using propensity score matching. Duplex ultrasound parameters, such as renal length difference between non-lesion side and lesion side within patient, trans-lesion peak systolic velocity and renal aortic ratio, were compared between cases and controls, and the area under the receiver operating characteristic curve (AUROC) was charted to predict ISR. After propensity score matching, 28 cases were matched in the pre-stenting period and 16 cases in the early post-stenting time period. Pre-stenting renal length difference, early post-stenting peak systolic velocity and renal aortic ratio showed significant differences in case-control comparisons. Early post-stenting peak systolic velocity (AUROC: 0.826, cutoff: 141 cm/s) and renal aortic ratio (AUROC: 0.770, cutoff: 1.75) performed well in predicting significant ISR and may serve as non-invasive markers in ISR surveillance.

A room-temperature ferroelectric semimetal.

Coexistence of reversible polar distortions and metallicity leading to a ferroelectric metal, first suggested by Anderson and Blount in 1965, has so far remained elusive. Electrically switchable intrinsic electric polarization, together with the direct observation of ferroelectric domains, has not yet been realized in a bulk crystalline metal, although incomplete screening by mobile conduction charges should, in principle, be possible. Here, we provide evidence that native metallicity and ferroelectricity coexist in bulk crystalline van der Waals WTe2 by means of electrical transport, nanoscale piezoresponse measurements, and first-principles calculations. We show that, despite being a Weyl semimetal, WTe2 has switchable spontaneous polarization and a natural ferroelectric domain structure at room temperature. This new class of materials has tantalizing potential for functional nanoelectronics applications.

A Low-Cost Highly Configurable Phantom for Simulation of Imaging-Guided Endocavitary Procedures.

We developed a method to create customizable phantoms suitable for endocavitary imaging and interventional research, based on the fabrication of an acrylic phantom mold, and development of a phantom matrix composed of gelatin, agar, graphite particles, and propanol. Our phantom was mechanically stable, easily fabricated, and highly adjustable, and its ultrasound (US) and magnetic resonance imaging (MRI) scans showed the qualification for the procedure guidance compared with the human prostate image using the same US system. To test the feasibility of the phantom for the research, the seeds placement guided by MRI/US fusion was performed, and the overall test error (distance from the seed center to the virtual lesion center in olives) was 2.59 ± 0.59 mm. We have created a simple, low-cost, configurable, gelatin-based phantom and tested its feasibility for simulating endorectal interventional US procedures. The design of the phantom mold and matrix is likely to be useful to the broader medical training community, and the preliminary data from the experiment of MRI/US-guided seeds placement showed its potential to test the clinical hypothesis in US research.

Antisymmetric magnetoresistance in van der Waals Fe3GeTe2/graphite/Fe3GeTe2 trilayer heterostructures.

With no requirements for lattice matching, van der Waals (vdW) ferromagnetic materials are rapidly establishing themselves as effective building blocks for next-generation spintronic devices. We report a hitherto rarely seen antisymmetric magnetoresistance (MR) effect in vdW heterostructured Fe3GeTe2 (FGT)/graphite/FGT devices. Unlike conventional giant MR (GMR), which is characterized by two resistance states, the MR in these vdW heterostructures features distinct high-, intermediate-, and low-resistance states. This unique characteristic is suggestive of underlying physical mechanisms that differ from those observed before. After theoretical calculations, the three-resistance behavior was attributed to a spin momentum locking induced spin-polarized current at the graphite/FGT interface. Our work reveals that ferromagnetic heterostructures assembled from vdW materials can exhibit substantially different properties to those exhibited by similar heterostructures grown in vacuum. Hence, it highlights the potential for new physics and new spintronic applications to be discovered using vdW heterostructures.

The value of conventional echocardiographic and tissue doppler imaging in the diagnosis of cardiac amyloidosis.

Transthoracic echocardiographic characteristics of 17 cases of cardiac amyloidosis (CA), a rare disease in China, were analyzed in order to improve the understanding of the disease. Seventeen cases of biopsy-proven CA, admitted to Wuhan Union Hospital from June 1994 to September 2008 were retrospectively reviewed. Twenty normal volunteers served as control group. Left atrial and ventricular functions and mitral inflow velocity were measured by two-dimensional, and Doppler echocardiography, and tissue Doppler imaging (TDI)-derived peak systolic wall motion velocities (Sv), peak early diastolic wall motion velocities (Ev), and peak late diastolic wall motion (Av) were measured at the septum, lateral, inferior and anterior corners of mitral annulus from the apical 4- and 2 chamber views. Compared with the control group, the interventricular septal thickness (IVSd), the left ventricular posterior wall (LVPWd), right ventricular transverse diameter (RVTDd) near the end of diastole and the interauricular septum thickness (IASs), left atrial anteroposterior diameter (LAADs), right atrial transverse diameter (RATDs) near the end of systole were increased significantly (all P<0.05) and left ventricular ejection fraction (LVEF) decreased (P<0.05) in the CA group. Compared with the control group, Sv, Ev at each wall and Av at almost all walls were significantly decreased in the CA group. In the CA group, Myocardial echoes of interventricular septum and free wall of left ventricle were enhanced evidently and distributed unevenly. The echoes presented as ground glass-like images, with some spotty hyper echoes. Both atria were enlarged, and LVEF decreased, with diastolic function impaired, and mild-moderate hydropericardium found in the CA group. It was concluded that echocardiography was a relatively sensitive and highly specific non-invasive method for the diagnosis of CA.

[Left ventricular rotation and twist in patients with hypertrophic cardiomyopathy evaluated by two-dimensional ultrasound speckle-tracking imaging].

OBJECTIVE: To assess the left ventricular rotation and twist in patients with hypertrophic cardiomyopathy (HCM) by 2-dimensional ultrasound speckle-tracking imaging (STI). METHODS: Two-dimensional images of left ventricule (LV) at basal and apical short-axis views were acquired in 20 patients with HCM and 20 healthy subjects to evaluate LV rotation. LV twist were defined as rate of apical LV rotation to the basal. Peak rotation (Prot) and the time to Prot in basal and apical short axis views were measured separately. Peak twist (Ptw), twist at aortic valve closure (AVCtw), twist at mitral valve opening (MVOtw), untwisting rate (Untw R), and half time of untwisting (HTU) were calculated. RESULTS: Compared with the control group, the value of Prot-MV, Prot-AP, Ptw, time to Ptw, AVCtw, MVOtw, and HTU significantly increased (all P < 0.05) and the Untw R significantly decreased (P < 0.05) in the HCM group. In the HCM group, time to Prot in apical view was significantly higher than that in basal view. CONCLUSION: STI can noninvasively evaluate the characteristics of LV twist and rotation in patients with HCM.