First-principles study of vacancy defects at interfaces between monolayer MoS2 and Au

The performance of MoS₂ based devices is closely related to the quality and defect morphology of the monolayer MoS₂ deposited on metal. First-principles calculations were performed to investigate the vacancy effects of Au–mMoS₂ contact. Four possible S-vacancy and a Mo-vacancy were considered in our calculations. Energetic studies show that S-vacancies are easier to form than Mo-vacancy in Au–mMoS₂ contact, while S-vacancy (hollow site at interface, V_S4) has the lowest formation energy under Mo-rich environments. Electron and charge redistribution analysis of defective Au–mMoS₂ contact indicate that the lower contact resistance and higher electron injection efficiency of defective Au–MoS₂ contact than perfect ones. Notably, the S-vacancy at top layer showed better electronic performance than that at bottom layer of monolayer MoS₂ in the contact. High quality n-type Au–mMoS₂ contact can therefore be expected through defect engineering.

Energetically favorable S(hollow)-vacancy has lower contact resistance and higher electron injection efficiency, resulting in better electronic performance in defective Au–MoS₂ contact.

Coronavirus disease 2019: a clinical review

In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in Wuhan, China, and it subsequently spread in many countries around the world. Many efforts have been applied to control and prevent the spread of COVID-19, and many scientific studies have been conducted in a short period of time. Here we present an overview of the viral structure, pathogenesis, diagnosis, and clinical features of COVID-19 based on the current state of knowledge, and we compare its clinical characteristics with SARS and Middle East Respiratory Syndrome (MERS). Current researches on potentially effective treatment alternatives are discussed. We hope this review can help medical workers and researchers around the world contain the current COVID-19 pandemic.

Current updates on the role of reactive oxygen species in bladder cancer pathogenesis and therapeutics

Bladder cancer (BCa) is the fourth most common urological malignancy in the world, it has become the costliest cancer to manage due to its high rate of recurrence and lack of effective treatment modalities. As a natural byproduct of cellular metabolism, reactive oxygen species (ROS) have an important role in cell signaling and homeostasis. Although up-regulation of ROS is known to induce tumorigenesis, growing evidence suggests a number of agents that can selectively kill cancer cells through ROS induction. In particular, accumulation of ROS results in oxidative stress-induced apoptosis in cancer cells. So, ROS is a double-edged sword. A modest level of ROS is required for cancer cells to survive, whereas excessive levels kill them. This review summarizes the up-to-date findings of oxidative stress-regulated signaling pathways and transcription factors involved in the etiology and progression of BCa and explores the possible therapeutic implications of ROS regulators as therapeutic agents for BCa.

Feasibility of three-dimensional constructive interference in steady state sequences for evaluating the anterolateral ligament

AIM

The purpose of the study was to determine the feasibility of three-dimensional (3D) constructive interference in steady state (CISS) sequences for evaluating the anterolateral ligament (ALL).

MATERIALS AND METHODS

Magnetic resonance imaging (MRI) of the right knee joint in 30 healthy volunteers was performed using a 3 T MRI machine. Axial T2-weighted imaging with fat saturation (T2WI-FS), coronal proton-density-weighted imaging with fat saturation (PDWI-FS), and 3D-CISS were included in the protocol. Multiplanar reconstruction (MPR) and rotating stretched curved planar reconstructions (CPRs) of the ALL at 30°, 60°, 90°, 120°, and 150° were generated from the 3D-CISS images. The visibility of the femoral part, meniscal part, tibial part, meniscal insertion, femoral footprint, and tibial footprint of the ALL on the imaging of all sequences was recorded.

RESULTS

Based on the CPR of 3D-CISS MRI, the presence of tibial and femoral footprints of the ALL was rated superior to MPR and PDWI-FS (96.67% and 96.67%, respectively; p<0.017). Rotating CPR of 3D-CISS MRI imaging was rated superior to PDWI-FS with respect to the tibial part, meniscal part, and meniscal insertion of the ALL (96.67%, 83.33%, and 83.33%, respectively; p<0.05). Rotating CPR of 3D-CISS MRI was rated superior to PDWI-FS with respect to the femoral part of the ALL, but the difference was not statistically significant (p=0.095). The angle between the ALL and lateral collateral ligament (LCL) on the oblique sagittal image was 18.34±1.88°.

CONCLUSIONS

The MRI 3D-CISS sequences significantly enhanced the ability to identify the ALL compared to the 2D MRI sequences.

Search for Sterile Neutrinos in MINOS and MINOS+ Using a Two-Detector Fit

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin^{2}θ_{24} for most values of the sterile neutrino mass splitting Δm_{41}^{2}>10^{-4}  eV^{2}.

Revealing Color Forces with Transverse Polarized Electron Scattering

The Spin Asymmetries of the Nucleon Experiment measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40° and covered a wide range in Bjorken x (0.3<x<0.8). Proportional to an average color Lorentz force, the twist-3 matrix element, d[over ˜]_{2}^{p}, was extracted from the measured asymmetries at Q^{2} values ranging from 2.0 to 6.0  GeV^{2}. The data display the opposite sign compared to most quark models, including the lattice QCD result, and an unexpected scale dependence. Furthermore, when combined with the neutron data in the same Q^{2} range the results suggest a flavor independent average color Lorentz force.

Skeletal muscle mitoflashes, pH, and the role of uncoupling protein-3

Mitochondrial reactive oxygen species (ROS) are important cellular signaling molecules, but can cause oxidative damage if not kept within tolerable limits. An important proximal form of ROS in mitochondria is superoxide. Its production is thought to occur in regulated stochastic bursts, but current methods using mitochondrial targeted cpYFP to assess superoxide flashes are confounded by changes in pH. Accordingly, these flashes are generally referred to as 'mitoflashes'. Here we provide regulatory insights into mitoflashes and pH fluctuations in skeletal muscle, and the role of uncoupling protein-3 (UCP3). Using quantitative confocal microscopy of mitoflashes in intact muscle fibers, we show that the mitoflash magnitude significantly correlates with the degree of mitochondrial inner membrane depolarization and ablation of UCP3 did not affect this correlation. We assessed the effects of the absence of UCP3 on mitoflash activity in intact skeletal muscle fibers, and found no effects on mitoflash frequency, amplitude or duration, with a slight reduction in the average size of mitoflashes. We further investigated the regulation of pH flashes (pHlashes, presumably a component of mitoflash) by UCP3 using mitochondrial targeted SypHer (mt-SypHer) in skeletal muscle fibers. The frequency of pHlashes was significantly reduced in the absence of UCP3, without changes in other flash properties. ROS scavenger, tiron, did not alter pHlash frequency in either WT or UCP3KO mice. High resolution respirometry revealed that in the absence of UCP3 there is impaired proton leak and Complex I-driven respiration and maximal coupled respiration. Total cellular production of hydrogen peroxide (H₂O₂) as detected by Amplex-UltraRed was unaffected. Altogether, we demonstrate a correlation between mitochondrial membrane potential and mitoflash magnitude in skeletal muscle fibers that is independent of UCP3, and a role for UCP3 in the control of pHlash frequency and of proton leak- and Complex I coupled-respiration in skeletal muscle fibers. The differential regulation of mitoflashes and pHlashes by UCP3 and tiron also indicate that the two events, though may be related, are not identical events.

Accuracy of interferon-γ-induced protein 10 for diagnosing latent tuberculosis infection: a systematic review and meta-analysis

BACKGROUND

Effective diagnostic methods for detecting latent tuberculosis infection (LTBI) are important for its eradication. A number of studies have evaluated the use of interferon-γ-induced protein 10 (IP-10), which is elevated after tuberculosis infection, as a biomarker for LTBI, but conclusive results regarding its effectiveness have not been reported.

OBJECTIVES

Our objective was to assess the diagnostic value of IP-10 for LTBI.

DATA SOURCES

We searched the PubMed, Embase, the Cochrane Library and Web of Science databases to find eligible studies.

STUDY ELIGIBILITY CRITERIA

We included cohort, case-control and cross-sectional studies that evaluated IP-10 in LTBI participants in comparison with tuberculin skin tests (TST) and interferon-γ release assays (IGRA).

PARTICIPANTS

Individuals with LTBI and uninfected participants.

INTERVENTIONS

IP-10 (index test) compared with TST and IGRA (reference standard) for diagnosing LTBI.

METHODS

PubMed, Embase, the Cochrane Library, and Web of Science databases were searched up to June 2018. A hierarchical summary receiver operating characteristic (HSROC) model was used to evaluate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and HSROC curve for the diagnostic efficiency of IP-10.

RESULTS

Twelve studies including 1023 participants and 1122 samples were included. The overall pooled sensitivity was 0.85 (95% CI 0.80-0.88), specificity was 0.89 (95% CI 0.84-0.92), PLR was 7.55 (95% CI 5.20-10.97), NLR was 0.17 (95% CI 0.13-0.22) and DOR was 44.23 (95% CI 28.86-67.79), indicating a high accuracy for diagnosing LTBI. Based on a meta-regression analysis, high-burden countries, study design, IP-10 method, reference standard and the IP-10 cut-off could not explain the heterogeneity (p >0.05).

CONCLUSIONS

Our results suggested that IP-10 is a promising biomarker for the diagnosis of LTBI.

[Safety and efficacy of percutaneous intervention for children with combined congenital heart abnormality solely guided by transthoracic echocardiography]

Objective: To investigate the safety and efficacy of percutaneous intervention of children with combined congenital heart abnormality solely guided by transthoracic echocardiography (TTE) . Methods: From September 2015 to June 2017, 21 children with combined congenital heart abnormality undergoing percutaneous interventional guided by TTE in Fuwai hospital were enrolled in our study, and the clinical data were retrospective analyzed. The atrial septal defect(ASD) closure, ventricular septal defect(VSD) closure, patent ductus arteriosus(PDA) closure or balloon pulmonary valvuloplasty were performed under the guidance of TTE. The procedural effect was evaluated by TTE after operation. The patients were followed up after discharged from the hospital. Results: The age was (37.3±11.6) months, and there were 9 male and 12 female patients. There were 4 cases with ASD and VSD, 6 cases with VSD and PDA, 6 cases with ASD and PDA, 2 cases with VSD and pulmonary stenosis, 3 cases with ASD and pulmonary stenosis. The operations were successfully performed in all patients. No one required extra X ray guidance or open heart surgery. The operation time was (44.6±7.5)min. All patients did not require blood transfusion, inotropic support, and analgesia. There were no complications such as peripheral vascular injury and pericardialeffusion after the operation. The length of hospital stay time was (3.5±0.6) days. All patients were recovered well. The follow-up was (17.6±5.2) months, and post-procedural conduction disturbances, residual shunts, occlude fall off, thrombosis, and new onset of valvular regurgitation were not observed in these patients. Conclusion: Percutaneous interventional of children with combined congenital heart abnormality solely guided by TTE is safe and effective, and the procedure can avoid the potential injuries of X ray and contrast agent.

Gestational dyslipidaemia and adverse birthweight outcomes: a systematic review and meta-analysis

BACKGROUND

Low and high birthweight is known to increase the risk of acute and longer-term adverse outcomes, such as stillbirth, infant mortality, obesity, type 2 diabetes and cardiovascular diseases. Gestational dyslipidaemia is associated with a numbers of adverse birth outcomes, but evidence regarding birthweight is still inconsistent to reliably inform clinical practice and treatment recommendations.

OBJECTIVE

The aim of this study was to explore the relationship between maternal gestational dyslipidaemia and neonatal health outcomes, namely, birthweight, metabolic factors and inflammatory parameters.

METHODS

We searched systematically Embase, MEDLINE, PubMed, CINAHL Plus and Cochrane Library up to 1 August 2016 (with an updated search in MEDLINE at the end of July 2017) for longitudinal studies that assessed the association of maternal lipid levels during pregnancy with neonatal birthweight, or metabolic and inflammatory parameters up to 3 years old.

RESULTS

Data from 46 publications including 31,402 pregnancies suggest that maternal high triglycerides and low high-density-lipoprotein cholesterol levels throughout pregnancy are associated with increased birthweight, higher risk of large for gestational age and macrosomia and lower risk of small-for-gestational age. The findings were consistent across the studied populations, but stronger associations were observed in women who were overweight or obese prior to pregnancy.

CONCLUSIONS

This meta-analysis suggested that the potential under-recognized adverse effects of intrauterine exposure to maternal dyslipidaemia may warrant further investigation into the relationship between maternal dyslipidaemia and birthweight in large prospective cohorts or in randomized trials.

PIG3 suppresses gastric cancer proliferation by regulating p53- mediated apoptosis

Gastric cancer (GC), the third leading cause of cancer mortality and the fifth most common cancer in the world, still is an important health problem worldwide. P53-inducible gene 3 (PIG3) was initially isolated in an investigation to identify the genes that were induced by p53 in human colorectal cancer cells. PIG3 can also regulate the stability of p53 through suppressing the process of the MDM2-mediated ubiquitination of p53. The aim of this study is to explore the expression level of PIG3 in human GC and further investigate the function and mechanism of PIG3 in human GC. Five cell lines and 30 matched GC tissue samples and adjacent tissue samples were used for this study, and MTT assay, colony formation assay, flow cytometry analysis and Western blot were carried out. Expression of PIG3 was found to be frequently reduced in GC. Restoration of the expression of PIG3 inhibited cell proliferation, induced cell apoptosis and further activated P53 signaling in BGC823 cells. In conclusion, we demonstrated that expression of PIG3 is frequently reduced in GC tissue, and PIG3 suppressed human GC growth through p53- mediated apoptosis. PIG3 may act as a potential diagnostic marker and a potential therapeutic target of GC.