Tuning Dzyaloshinskii-Moriya interaction via an electric field at the Co/h-BN interface

The Dzyaloshinsky-Moriya interaction (DMI) at the Co/h-BN interface can emerge and be enhanced by applying a downward electric field. The height of the Co atom relative to the h-BN layer with the electric field determines the variation of DMI. One half reduction of J₁ is beneficial to generate skyrmions. Tuning the DMI by an electric field sheds new light for research on skyrmions.

Tissue factor cytoplasmic domain exacerbates post-infarct left ventricular remodeling via orchestrating cardiac inflammation and angiogenesis

Introduction

The coagulation protein tissue factor (TF) regulates inflammation and angiogenesis via its cytoplasmic domain in infection, cancer and diabetes. While TF is highly abundant in the heart and implicated in cardiac injuries and dysfunction, the contribution of its cytoplasmic domain in cardiac pathology remains unclear.

Purpose

We aimed to investigate the contribution of the cytoplasmic domain of TF to post-infarct myocardial injury and adverse left ventricular (LV) remodeling.

Methods and results

Myocardial infarction was induced by permanent occlusion of the left anterior descending coronary artery. Male mice with C57BL/Jax background were used for the study. Compared with wild-type mice, mice lacking the TF cytoplasmic domain (TFΔCT) had a higher survival rate (90.5% versus 70%, p=0.0298) during a 28-day follow-up after myocardial infarction. Among surviving mice, TFΔCT mice had better cardiac function and less LV remodeling (ESV: 114.5±13.1mL for WT, 67.06±10.8mL for TFΔCT, p<0.001; EDV: 146.6±12.4mL for WT, 99.97±11.71mL for TFΔCT, p<0.001) than wild-type mice. Bone marrow chimerism indicated that deletion of the TF cytoplasmic domain in either bone marrow-derived cells or cardiac resident cells could alleviate post-infarct cardiac dysfunction. Speckle-tracking strain analysis revealed that the overall improvement of post-infarct cardiac performance in TFΔCT mice was attributed to reduced myocardial deformation in the peri-infarct region (strain-%: 11.14±0.97 for WT, 15.34±1.10 for TFΔCT, p=0.007; strain rate-/s: 3.89±0.26 for WT, 5.18±0.21 for TFΔCT, p=0.0005). Histological analysis demonstrated that TFΔCT hearts had in the infarct area greater proliferation of endothelial cells and myofibroblasts accompanied with better scar formation. Compared with wild-type hearts, infarcted TFΔCT hearts showed less infiltration of proinflammatory cells with concomitant lower expression of protease-activated receptor-1 (PAR1)-Rac1 axis. Furthermore, infarcted TFΔCT hearts presented markedly higher peri-infarct vessel density associated with enhanced endothelial cell proliferation and higher expression of PAR2 and PAR2-associated pro-angiogenic pathway factors.

Conclusions

Our findings demonstrate that the TF cytoplasmic domain exacerbates post-infarct cardiac injury and adverse LV remodeling via differential regulation of inflammation and angiogenesis. Targeted inhibition of the TF cytoplasmic domain-mediated intracellular signaling may ameliorate post-infarct LV remodeling without perturbing coagulation.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National University Health System of Singapore

Allergic contact dermatitis in healthcare workers

BACKGROUND

Allergic contact dermatitis is a common occupational skin disease among healthcare workers (HCWs).

AIMS

This study describes causes of allergic contact dermatitis in New Zealand HCWs.

METHODS

All HCWs undergoing patch testing between July 2008 and January 2020 at a public hospital patch test clinic and between June 2019 and January 2020 at a private dermatology clinic were included. Data collected included patient demographics, occupation, results of patch testing and pre- and post-patch test diagnoses.

RESULTS

Out of 837 patients tested, 67 were HCWs. The mean age of HCWs was 41 years (SD 14) and 58 (87%) were female. The most common occupations were nurses (40%), allied health (22%) and doctors (18%). Forty-six (69%) patients had a background of atopic dermatitis. Hand dermatitis was the most common presentation (49%), followed by facial/neck dermatitis (25%). Thirty-eight (57%) had at least one positive reaction on patch testing, including 19 (28%) with a positive result of current relevance. There were 16 relevant reactions to rubber accelerators, 11 to fragrances, 10 to preservatives and 6 to corticosteroids. The most frequent relevant allergens were methylisothiazolinone/methylchloroisothiazolinone (4%), hydroxyisohexyl 3-cyclohexene carboxaldehyde (4%) and methylisothiazolinone (4%).

CONCLUSIONS

The most common allergens in HCWs were rubber chemicals, fragrances, preservatives and topical corticosteroids. Important allergens for patch testing HCWs are outlined, in particular, those with hand dermatitis should be tested to a rubber series.

Do patient characteristics matter when calculating sample size for eczema clinical trials?

Background

The Patient‐Oriented Eczema Measure (POEM) is the core outcome instrument recommended for measuring patient‐reported atopic eczema symptoms in clinical trials. To ensure that the statistical significance of clinical trial results is meaningful, trials are often designed by specifying the target difference in the primary outcome as part of the sample size calculation. One method used to specify the target difference is a score that corresponds to a standardized effect size.

Objectives

to assess how the standardized effect size of POEM scores vary across age, gender, ethnicity and disease severity.

Methods

This study combined data from five UK‐based randomized clinical trials of eczema treatments in order to assess differences in self‐reported eczema symptoms (POEM) corresponding to a standardized effect size (0.5 SD of baseline POEM scores) across age, gender, ethnicity and disease severity.

Results

POEM scores corresponding to 0.5 SD_(baseline) were remarkably consistent across participants of varying ages, gender, ethnicity and disease severity from datasets of five UK trials in children (range 2.99–3.45).

Conclusions

This study provides information that can support those designing clinical trials to determine their sample size and can aid individuals interpreting trial results. Further exploration of differences in populations beyond the United Kingdom is needed.

Multiharmonic Correlations of Different Flow Amplitudes in Pb-Pb Collisions at sqrt[s_{NN}]=2.76 TeV

The event-by-event correlations between three flow amplitudes are measured for the first time in Pb-Pb collisions, using higher-order symmetric cumulants. We find that different three-harmonic correlations develop during the collective evolution of the medium when compared to correlations that exist in the initial state. These new results cannot be interpreted in terms of previous lower-order flow measurements since contributions from two-harmonic correlations are explicitly removed in the new observables. A comparison to Monte Carlo simulations provides new and independent constraints for the initial conditions and system properties of nuclear matter created in heavy-ion collisions.

P–363 Poor Ovarian Response is Associated with Anti-ovarian Antibody, and Pro-inflammatory Immune Responses in Women Underwent Assisted Reproductive Technology Cycles

Study question

To investigate if the anti-ovarian antibody (AOA) is associated with poor ovarian response (POR) and pro-inflammatory immune responses in women undergoing assisted reproductive technology (ART) cycles.

Summary answer

The POR patients have a higher prevalence of AOAs. Women with autoimmune POR (POR(+)/AOA(+)) have dysregulated pro-inflammatory immune responses and metabolic factors.

What is known already

It has been proved that AOAs play important role in diseases that related to human reproduction such as premature ovarian failure (POF) which also termed as premature ovarian insufficiency (POI), infertility, polycystic ovary syndrome (PCOS), in vitro fertilization (IVF) implantation failure, and in poor ovarian response in IVF stimulation. The POR women had elevated inflammatory immune responses: increased NK cell count and cytotoxicity, B cell counts, Th1/Th2 ratio and elevated metabolic factors such as higher homocysteine and plasminogen activator inhibitor–1 (PAI–1) level.

Study design, size, duration

This study is a retrospective cohort study between December 2015 and February 2019. 248 women who underwent ART cycles were included. Study patients were divided into four groups based on AOA test and POR diagnose defined by the European Society of Human Reproduction and Embryology consensus: POR(-)/AOA (-) group (N = 148), POR(+)/AOA(-) group (N = 34), POR (-)/AOA (+) group (N = 44), POR(+)/AOA(+) group (N = 22). Peripheral blood was collected during the early follicular phase when they enter the program.

Participants/materials, setting, methods

The natural killer (NK) cell levels and cytotoxicity, T helper (Th) 1/Th2 cell ratios were measured by flowcytometry. Anti-phospholipid Antibodies (APA) was tested by enzyme linked immunosorbent assay (ELISA). AOA, 25 (OH) vitamin D level, homocysteine, PAI–1 level was tested by Immunofluorescence Assay.One way ANOVA was applied to compare the continuous variables among study groups. Chi-squared analysis or Fisher’s exact test were performed to compare the categorical variables.

Main results and the role of chance

The POR patients have a significantly higher prevalence of AOA than non-POR patients (39.3% vs. 22.9%, P = 0.017, OR 2.176 95% CI 1.156–4.099). Peripheral blood CD56+ NK cell level (%), NK cytotoxicity, CD19+CD5+ B–1 cell level (%) and IFN-g/IL–10 producing Th1/Th2 cell ratios were significantly higher in POR(+)/AOA(+) group than those of other groups (P < 0.05, P < 0.05, P < 0.05, P < 0.05, respectively). TNF-a/IL–10 producing Th1/Th2 cell ratio of POR(+)/AOA (+) group was significantly higher than those of POR(+)/AOA(-) and POR(-)/AOA(-) groups (P < 0.05, respectively). Peripheral blood homocysteine and vitamin D levels of the POR(+)/AOA (+) group were significantly lower than those of other groups (P < 0.005, respectively). Peripheral blood PAI–1 level of POR(+)/AOA(+) group was significantly higher than that of POR(-)/AOA(-) group (P < 0.05). In POR(+)/AOA(+) group, the prevalence of antiphospholipid antibody was significantly higher than that of POR(+)/AOA(-) group (54.5% vs 20.5%, P = 0.005, OR 4.667, 95% CI 1.532–14.216).

Limitations, reasons for caution

This was a single center study, results need to be validated across different center and study population.

Wider implications of the findings: The diagnostic and therapeutic approaches for AOA (+) autoimmune POR patients should be differentiated from those for non-autoimmune POR.

Trial registration number

Not applicable

Targeting STING attenuates ROS induced intervertebral disc degeneration

OBJECTIVE

DNA damage induced by ROS is considered one of the main causes of nucleus pulposus (NP) cells degeneration during the progression of intervertebral disc degeneration (IVDD). cGAS-STING pathway acts as DNA-sensing mechanism for monitoring DNA damage. Recent studies have proved that cGAS-STING contributes to the development of various diseases by inducing inflammation, senescence, and apoptosis. This work explored the role of STING, the main effector of cGAS-STING signaling pathway, in NP degeneration.

METHOD

Immunohistochemistry was conducted to measure STING protein levels in the nucleus pulposus tissues from human and puncture-induced IVDD rat models. TBHP induces degeneration of nucleus pulposus cells in vitro. For in vivo experiments, lv-NC or lv-STING were injected into the central intervertebral disc space. The degeneration level of IVDD was assessed by MRI, X-ray, HE, and Safranin O staining.

RESULTS

We found that the expression of STING was upregulated in human and rat degenerated NP tissue as well as in TBHP-treated NP cells. Overexpression of STING promoted the degradation of extracellular matrix; it also promoted apoptosis and senescence of TBHP-treated and untreated NP cells. Knock-down of STING significantly reversed these effects. Mechanistically, STING activated IRF3, whereas blockage of IRF3 attenuated STING-induced apoptosis, senescence and ECM degradation. In vivo experiments revealed that STING knock-down alleviated puncture-induced IVDD development.

CONCLUSION

STING promotes IVDD progress via IRF3, while suppression of STING may be a promising treatment for IVDD.

Soft-Dielectron Excess in Proton-Proton Collisions at sqrt[s]=13 TeV

A measurement of dielectron production in proton-proton (pp) collisions at sqrt[s]=13  TeV, recorded with the ALICE detector at the CERN LHC, is presented in this Letter. The data set was recorded with a reduced magnetic solenoid field. This enables the investigation of a kinematic domain at low dielectron (ee) invariant mass m_{ee} and pair transverse momentum p_{T,ee} that was previously inaccessible at the LHC. The cross section for dielectron production is studied as a function of m_{ee}, p_{T,ee}, and event multiplicity dN_{ch}/dη. The expected dielectron rate from hadron decays, called hadronic cocktail, utilizes a parametrization of the measured η/π^{0} ratio in pp and proton-nucleus collisions, assuming that this ratio shows no strong dependence on collision energy at low transverse momentum. Comparison of the measured dielectron yield to the hadronic cocktail at 0.15<m_{ee}<0.6  GeV/c^{2} and for p_{T,ee}<0.4  GeV/c indicates an enhancement of soft dielectrons, reminiscent of the "anomalous" soft-photon and soft-dilepton excess in hadron-hadron collisions reported by several experiments under different experimental conditions. The enhancement factor over the hadronic cocktail amounts to 1.61±0.13(stat)±0.17(syst,data)±0.34(syst,cocktail) in the ALICE acceptance. Acceptance-corrected excess spectra in m_{ee} and p_{T,ee} are extracted and compared with calculations of dielectron production from hadronic bremsstrahlung and thermal radiation within a hadronic many-body approach.

Pcsk9 Knockout Aggravated Experimental Apical Periodontitis via LDLR

Apical periodontitis (AP), an inflammatory lesion around the apex of tooth roots, is mostly caused by dental pulp infection. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a vital role in regulating cholesterol homeostasis by targeting low-density lipoprotein receptor (LDLR) and participates in bacterium-induced chronic periodontitis. However, the roles of PCSK9 in AP are unknown. Here, we investigated its role in AP by using Pcsk9^-/- mice. Micro-computed tomography scanning and histological staining revealed that the periapical bone loss of Pcsk9^-/- mice was greater than that of wild-type (WT) mice, and increased expression of inflammation-related factors tumor necrosis factor α (TNF-α) and interleukin (IL)-6 was also observed. Immunofluorescence staining and quantitative real-time polymerase chain reaction showed PCSK9 expression in bone marrow macrophages (BMMs) was increased after treatment with lipopolysaccharide (LPS). This finding was consistent with the in vivo results that the expression level of PCSK9 in exposed WT mice increased compared with that in unexposed WT mice. After LPS challenge, the expression levels of TNF-α, IL-1β, and IL-6 in BMMs were increased, and Pcsk9 knockout aggravated the expression of these inflammatory factors. The number of osteoclasts positive for tartrate-resistant acid phosphatase staining around the apical lesion in Pcsk9^-/- mice was higher than that in WT mice. Then BMMs underwent the osteoclast differentiation. Pcsk9 knockout BMMs induced increased and larger osteoclasts. While this effect of Pcsk9 knockout was abolished by the addition of Ldlr small interfering RNA, revealing that Pcsk9 knockout increased osteoclastogenesis was dependent on the LDLR. Immunohistochemistry staining showed increased expression level of LDLR in exposed Pcsk9^-/- periapical areas. In vitro experiments showed that LPS promoted the expression level of LDLR in Pcsk9^-/- BMMs and increased osteoclast formation ability, indicating that LPS promoted the elevation of osteoclasteogenesis caused by the Pcsk9 knockout. In conclusion, Pcsk9 deficiency aggravated the inflammatory response and promoted the osteoclastogenesis in an LDLR-dependent manner in AP experimental mice.

Elliptic Flow of Electrons from Beauty-Hadron Decays in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The elliptic flow of electrons from beauty hadron decays at midrapidity (|y|<0.8) is measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The azimuthal distribution of the particles produced in the collisions can be parametrized with a Fourier expansion, in which the second harmonic coefficient represents the elliptic flow, v_{2}. The v_{2} coefficient of electrons from beauty hadron decays is measured for the first time in the transverse momentum (p_{T}) range 1.3-6  GeV/c in the centrality class 30%-50%. The measurement of electrons from beauty-hadron decays exploits their larger mean proper decay length cτ≈500  μm compared to that of charm hadrons and most of the other background sources. The v_{2} of electrons from beauty hadron decays at midrapidity is found to be positive with a significance of 3.75  σ. The results provide insights into the degree of thermalization of beauty quarks in the medium. A model assuming full thermalization of beauty quarks is strongly disfavored by the measurement at high p_{T}, but is in agreement with the results at low p_{T}. Transport models including substantial interactions of beauty quarks with an expanding strongly interacting medium describe the measurement within uncertainties.

MicroRNA-147 inhibits myocardial inflammation and apoptosis following myocardial infarction via targeting HIPK2

OBJECTIVE

The incidence of acute myocardial infarction (AMI) is increasing year by year, and it has become one of the diseases with the highest mortality in humans. MicroRNAs (miRNAs) are involved in the regulation of many diseases, including AMI. This study aims to investigate the function of miR-147 in myocardial infarction (MI) and its underlying mechanism of action.

MATERIALS AND METHODS

Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) was used to detect miR-147, Bcl-2 mRNA, and Bax mRNA expressions. Enzyme-linked immunosorbent assay (ELISA) kits were used to detect the levels of inflammatory factors (TNF-α, IL-6, IL-β) and lactate dehydrogenase (LDH). Besides, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay was performed to detect cell viability. Cell apoptosis was observed using terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL). Moreover, echocardiography was utilized to measure cardiac function of rats. HIPK2 expression was detected by Western blot.

RESULTS

MiR-147 expression was significantly decreased in rat MI model and H2O2 treated H9c2 cells. H2O2 treatment increased the expression of inflammatory factors in H9c2 cells and induced apoptosis, while such effects were inhibited by overexpression of miR-147. Overexpression of miR-147 reversed the decrease in Bcl-2 expression and the increase in Bax expression in H9c2 cells caused by H2O2. In addition, overexpression of miR-147 could improve cardiac function and reduce serum LDH levels in myocardial infarction rats. Through TargetScan, we found that HIPK2 might have a binding site for miR-147. Moreover, overexpression of miR-147 could inhibit the expression of HIPK2.

CONCLUSIONS

In MI, miR-147 expression is decreased in the myocardium and overexpression of miR-147 can inhibit myocardial inflammation and apoptosis and improve cardiac function in rats via targeting HIPK2.

Modeling the Potential Impact of Norovirus Vaccination Among DoD Forces

INTRODUCTION

Norovirus, a contagious disease that spreads rapidly in close-quartered communities, has a debilitating effect in military settings, affecting troops' health, productivity, and mission-readiness. This research presents a model of norovirus transmission, testing the vaccination's effectiveness in military training centers.

METHODS

Transmission was modeled using structured ordinary differential equations, including symptomatic and asymptomatic infection, genetic resistance, vaccination, and herd-immunity effects, within a hypothetical cohort of trainees and support staff. The modeled vaccine had an efficacy of 72%, 4 weeks after a single dose in phase 2 clinical trials. The transmission model was calibrated against data from a norovirus outbreak in a university setting. Sensitivity and uncertainty analyses were performed on 22 parameters.

RESULTS

The greatest reduction in norovirus cases resulted from prophylactic environmental decontamination and vaccination of trainee and staff populations. These combined interventions prevented more than 6,800 cases of norovirus over the 10-year simulated period-a 15% reduction over the baseline scenario of no interventions. Implementing vaccination and environmental decontamination with an outbreak response threshold of 0.1%, prevented more than 5,300 infections; raising the threshold to 0.2% to 0.5% significantly reduced effectiveness. Environmental decontamination and contact reduction alone had little impact on overall norovirus cases.

CONCLUSIONS

Given vaccine characteristics, the model predicted that up to 15% of norovirus cases occurring in training settings over a 10-year period could be prevented by vaccinating all trainees and staff members immediately upon arrival on-base combined with continuous environmental decontamination. There was an impact on morbidity from implementing vaccination of trainees, alone and in combination with staff members. However, vaccinating staff alone prevented few cases over the simulation period, indicating the importance of trainees in norovirus transmission. Likewise, the negligible impact of environmental decontamination or contact reduction alone highlights the importance of addressing both person-to-person and environmental transmission together to minimize illnesses and training downtime.

Modeling Zika Vaccination Combined With Vector Interventions in DoD Populations

INTRODUCTION

Zika virus (ZIKV) is a mild febrile illness generally transmitted via the bite of infected Aedes species mosquitoes, including Aedes aegypti, with the potential to cause neurological complications. Nearly 200 U.S. military installations are located within areas where Aedes mosquitos are found, putting thousands of personnel at risk for infection with ZIKV. This analysis aims to quantify the benefits of interventions, including vaccination, to decrease the risk of ZIKV on U.S. military installations.

METHODS

The authors developed a dynamic transmission model to test the "effectiveness" of vaccination, personal protective measures (PPM), and mosquito control at reducing morbidity within U.S. military populations. ZIKV transmission was modeled as a compartmental susceptible-exposed-infected-recovered model tracking interactions between humans and mosquitos and incorporating seasonality of mosquito populations and the potential for herd immunity. The model included two-dose vaccination as well as symptomatic and asymptomatic infection. The model was calibrated against 2016 public health data in Puerto Rico; sensitivity analyses were performed on model parameters and interventions.

RESULTS

The greatest reduction in total modeled ZIKV cases resulted from vaccination combined with mosquito control and PPM. All three interventions at their highest estimated level of efficiency reduced ZIKV cases by 99.9% over the baseline case of low-level adherence to PPM. The addition of vaccination had limited additional benefit over effective vector control and PPM since the significant lag to vaccine-induced protection limited effectiveness of vaccination.

CONCLUSIONS

Given the current vaccine, the model predicted that up to 92.8% of Zika cases occurring in deployment settings over a 10-year period could be prevented by adding vaccination to current low-level PPM. Combining vaccination with other interventions can reduce cases further. A location-specific cost-benefit analysis would be a valuable contribution to outbreak control policy as it could evaluate the economic impact of the interventions versus the reduced level of illness and downtime in this setting.