Measurement of Prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) Production in Proton-Proton Collisions at sqrt[s]=13 TeV

The p_{T}-differential production cross sections of prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) charmed hadrons are measured at midrapidity (|y|<0.5) in pp collisions at sqrt[s]=13  TeV. This is the first measurement of Σ_{c}^{0,++} production in hadronic collisions. Assuming the same production yield for the three Σ_{c}^{0,+,++} isospin states, the baryon-to-meson cross section ratios Σ_{c}^{0,+,++}/D^{0} and Λ_{c}^{+}/D^{0} are calculated in the transverse momentum (p_{T}) intervals 2<p_{T}<12 and 1<p_{T}<24  GeV/c. Values significantly larger than in e^{+}e^{-} collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the Σ_{c}. The feed-down contribution to Λ_{c}^{+} production from Σ_{c}^{0,+,++} is also reported and is found to be larger than in e^{+}e^{-} collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronization mechanisms implemented in the models.

Measurement of the Cross Sections of Ξ_{c}^{0} and Ξ_{c}^{+} Baryons and of the Branching-Fraction Ratio BR(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/BR(Ξ_{c}^{0}→Ξ^{-}π^{+}) in pp Collisions at sqrt[s]=13 TeV

The p_{T}-differential cross sections of prompt charm-strange baryons Ξ_{c}^{0} and Ξ_{c}^{+} were measured at midrapidity (|y|<0.5) in proton-proton (pp) collisions at a center-of-mass energy sqrt[s]=13  TeV with the ALICE detector at the LHC. The Ξ_{c}^{0} baryon was reconstructed via both the semileptonic decay (Ξ^{-}e^{+}ν_{e}) and the hadronic decay (Ξ^{-}π^{+}) channels. The Ξ_{c}^{+} baryon was reconstructed via the hadronic decay (Ξ^{-}π^{+}π^{+}) channel. The branching-fraction ratio BR(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/BR(Ξ_{c}^{0}→Ξ^{-}π^{+})=1.38±0.14(stat)±0.22(syst) was measured with a total uncertainty reduced by a factor of about 3 with respect to the current world average reported by the Particle Data Group. The transverse momentum (p_{T}) dependence of the Ξ_{c}^{0}- and Ξ_{c}^{+}-baryon production relative to the D^{0} meson and to the Σ_{c}^{0,+,++}- and Λ_{c}^{+}-baryon production are reported. The baryon-to-meson ratio increases toward low p_{T} up to a value of approximately 0.3. The measurements are compared with various models that take different hadronization mechanisms into consideration. The results provide stringent constraints to these theoretical calculations and additional evidence that different processes are involved in charm hadronization in electron-positron (e^{+}e^{-}) and hadronic collisions.

Optofluidic Resonance of a Transparent Liquid Jet Excited by a Continuous Wave Laser

We report a new optofluidic resonating phenomenon that naturally links the optical radiation pressure, total internal reflection, capillary wave, and Rayleigh-Plateau instability together. When a transparent liquid jet is radiated by a focused continuous wave laser beam, the highly ordered periodic jet breakup is unexpectedly triggered and maintained. The capillary wave enables the liquid-gas interface to serve as a rotating mirror reflecting the laser beam in a wide range of angles, including the critical angle for total internal reflection. The liquid jet acts as an optical waveguide to periodically transmit the laser beam to the upstream of the jet. The periodic optical beam transmittance inside the liquid jet exerts time-dependent optical pressure to the jet that triggers the Rayleigh-Plateau instability. The jet breakup process locks in at the frequency corresponding to the peak growth rate of the Rayleigh-Plateau instability of the liquid jet, which agrees with the prediction from the dispersion relation of a traveling liquid jet.

Exploring Destination Choice Intention by Using the Tourism Photographic: From the Perspectives of Visual Esthetic Processing

This study aims to deepen the understanding of tourism photography by developing and testing a theoretical model that accounts for the relationships between visual esthetics and destination choice intention of tourists. Thus, we sought to use a stimulus-organism-response (S-O-R) paradigm to predict destination choice intention, which includes three variables related to visual esthetics: first impression, visual appeal, and esthetic emotion. We used the combination of self-reported and eye movement data to examine the cognitive processes of tourists that visual esthetic formation. We found that compared to the built environment and amateur esthetic images, natural environment and professional esthetic images can get (1) higher visual appeal, (2) better first impression, and (3) higher visual processing fluency (or less cognitive effort) and positive esthetic emotions. Furthermore, visual appeal, first impression, and esthetic emotion deriving from environment esthetics and photograph esthetics have a positive impact on destination choice intention. This study has practical implications for destination planning and management.

Organic Photovoltaics Printed via Sheet Electrospray Enabled by Quadrupole Electrodes

Developing manufacturing methods that are scalable and compatible with a roll-to-roll process with low waste of material has become a pressing need to transfer organic photovoltaics (OPVs) to a viable renewable energy source. For this purpose, various spray printing methods have been proposed. Among them, electrospray (ES) is an attractive option due to its negligible material waste, tunable droplet size, and tolerance to the substrate defects and roughness. Conventional ES with a circular spray footprint often makes the droplets well separated and unlikely to merge, giving rise to "coffee rings" which cause a rough and flawed film morphology. Here, a quadrupole electrode is introduced to generate a compressing electric field that squeezes the conical ES profile into the shape of a thin sheet. The numerical simulation and experimental data of the trajectories of sprayed droplets show that the quadrupole apparatus can effectively increase the long axis to short axis ratio of the oval spray footprint and hence bring droplets closer to each other and make the merging more likely for the deposited droplets. By promoting the merging of droplets, individual coffee rings are also suppressed. Thus, the quadrupole ES offers untapped opportunities for effectively reducing voids and improving the flatness of the ES-printed active layer. The devices with a PM6:N3 active layer printed by the sheet ES exhibited the highest power conversion efficiency (PCE) of up to 15.98%, which is a noticeable improvement over that (14.85%) of counterparts fabricated by a conventional conical ES. This is the highest PCE reported for ES-printed OPVs and is one of the most efficient spray-deposited OPVs so far. In addition, the all-spray-printed devices reached a PCE of 14.55%, which is also among the most efficient all-spray-printed OPVs.

Λ_{c}^{+} Production and Baryon-to-Meson Ratios in pp and p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV at the LHC

The prompt production of the charm baryon Λ_{c}^{+} and the Λ_{c}^{+}/D^{0} production ratios were measured at midrapidity with the ALICE detector in pp and p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. These new measurements show a clear decrease of the Λ_{c}^{+}/D^{0} ratio with increasing transverse momentum (p_{T}) in both collision systems in the range 2<p_{T}<12  GeV/c, exhibiting similarities with the light-flavor baryon-to-meson ratios p/π and Λ/K_{S}^{0}. At low p_{T}, predictions that include additional color-reconnection mechanisms beyond the leading-color approximation, assume the existence of additional higher-mass charm-baryon states, or include hadronization via coalescence can describe the data, while predictions driven by charm-quark fragmentation processes measured in e^{+}e^{-} and e^{-}p collisions significantly underestimate the data. The results presented in this Letter provide significant evidence that the established assumption of universality (colliding-system independence) of parton-to-hadron fragmentation is not sufficient to describe charm-baryon production in hadronic collisions at LHC energies.

Experimental Evidence for an Attractive p-ϕ Interaction

This Letter presents the first experimental evidence of the attractive strong interaction between a proton and a ϕ meson. The result is obtained from two-particle correlations of combined p-ϕ⊕ p[over ¯]-ϕ pairs measured in high-multiplicity pp collisions at sqrt[s]=13  TeV by the ALICE Collaboration. The spin-averaged scattering length and effective range of the p-ϕ interaction are extracted from the fully corrected correlation function employing the Lednický-Lyuboshits approach. In particular, the imaginary part of the scattering length vanishes within uncertainties, indicating that inelastic processes do not play a prominent role for the p-ϕ interaction. These data demonstrate that the interaction is dominated by elastic p-ϕ scattering. Furthermore, an analysis employing phenomenological Gaussian- and Yukawa-type potentials is conducted. Under the assumption of the latter, the N-ϕ coupling constant is found to be g_{N-ϕ}=0.14±0.03(stat)±0.02(syst). This work provides valuable experimental input to accomplish a self-consistent description of the N-ϕ interaction, which is particularly relevant for the more fundamental studies on partial restoration of chiral symmetry in nuclear medium.

Incorporating heterogeneous information in deep learning with informative meta-paths for community recommendations

Communities of interest promote knowledge sharing and discovery in social network platforms. However, platform users face difficulties of finding suitable communities, given their increasing number. Although recommendations have been proposed to help users find communities of interest, these methods ignore or exclude heterogeneous interactions between users and communities. In addition, widely used meta-paths help capture the complex semantic relation among entities but heavily rely on domain knowledge. In this study, we propose a novel recommendation model based on informative meta-path discovery in heterogeneous information networks and deep learning. Users, communities, relevant items and their relations are considered as entities in a heterogeneous information network, from where informative meta-paths are extracted on the basis of information theory to measure user-community similarities. Finally, similarities are incorporated in a deep learning model to predict whether target users join candidate communities. The proposed recommendation model is evaluated and compared against baseline methods using two data sets. Results demonstrate the superior performance of the present model in terms of precision, recall and F score.

Challenges in simulating and modeling the airborne virus transmission: A state-of-the-art review

Recently, the COVID-19 virus pandemic has led to many studies on the airborne transmission of expiratory droplets. While limited experiments and on-site measurements offer qualitative indication of potential virus spread rates and the level of transmission risk, the quantitative understanding and mechanistic insights also indispensably come from careful theoretical modeling and numerical simulation efforts around which a surge of research papers has emerged. However, due to the highly interdisciplinary nature of the topic, numerical simulations of the airborne spread of expiratory droplets face serious challenges. It is essential to examine the assumptions and simplifications made in the existing modeling and simulations, which will be reviewed carefully here to better advance the fidelity of numerical results when compared to the reality. So far, existing review papers have focused on discussing the simulation results without questioning or comparing the model assumptions. This review paper focuses instead on the details of the model simplifications used in the numerical methods and how to properly incorporate important processes associated with respiratory droplet transmission. Specifically, the critical issues reviewed here include modeling of the respiratory droplet evaporation, droplet size distribution, and time-dependent velocity profile of air exhaled from coughing and sneezing. According to the literature review, another problem in numerical simulations is that the virus decay rate and suspended viable viral dose are often not incorporated; therefore here, empirical relationships for the bioactivity of coronavirus are presented. It is hoped that this paper can assist researchers to significantly improve their model fidelity when simulating respiratory droplet transmission.

Visualization of the interaction of water aerosol and nanofiber mesh

Face masks play a critical role in reducing the transmission risk of COVID-19 and other respiratory diseases. Masks made with nanofibers have drawn increasingly more attention because of their higher filtration efficiency, better comfort, and lower pressure drop. However, the interactions and consequences of the nanofibers and microwater droplets remain unclear. In this work, the evolution of fibers made of polymers with different contact angles, diameters, and mesh sizes under water aerosol exposure is systematically visualized. The images show that capillarity is very strong compared with the elasticity of the nanofiber. The nanofibers coalesce irreversibly during the droplet capture stage as well as the subsequent liquid evaporation stage. The fiber coalescence significantly reduces the effective fiber length for capturing aerosols. The nanofiber mesh that undergoes multiple droplet capture/evaporation cycles exhibits a fiber coalescing fraction of 40%-58%. The hydrophobic and orthogonally woven fibers can reduce the capillary forces and decrease the fiber coalescing fraction. This finding is expected to assist the proper design, fabrication, and use of face masks with nanofibers. It also provides direct visual evidence on the necessity to replace face masks frequently, especially in cold environments.

Neutrophil Extracellular Traps Exacerbate Secondary Injury via Promoting Neuroinflammation and Blood-Spinal Cord Barrier Disruption in Spinal Cord Injury

As the first inflammatory cell recruited to the site of spinal cord injury (SCI), neutrophils were reported to be detrimental to SCI. However, the precise mechanisms as to how neutrophils exacerbate SCI remain largely obscure. In the present study, we demonstrated that infiltrated neutrophils produce neutrophil extracellular traps (NETs), which subsequently promote neuroinflammation and blood–spinal cord barrier disruption to aggravate spinal cord edema and neuronal apoptosis following SCI in rats. Both inhibition of NETs formation by peptidylarginine deiminase 4 (PAD4) inhibitor and disruption of NETs by DNase 1 alleviate secondary damage, thus restraining scar formation and promoting functional recovery after SCI. Furthermore, we found that NETs exacerbate SCI partly via elevating transient receptor potential vanilloid type 4 (TRPV4) level in the injured spinal cord. Therefore, our results indicate that NETs might be a promising therapeutic target for SCI.

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.

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.

Single-cell immune checkpoint landscape of PBMCs stimulated with Candida albicans

Immune checkpoints play various important roles in tumour immunity, which usually contribute to T cells’ exhaustion, leading to immunosuppression in the tumour microenvironment. However, the roles of immune checkpoints in infectious diseases, especially fungal infection, remain elusive. Here, we reanalyzed a recent published single-cell RNA-sequencing (scRNA-seq) data of peripheral blood mononuclear cells (PBMCs) stimulated with Candida albicans (C. albicans), to explore the expression patterns of immune checkpoints after C. albicans bloodstream infection. We characterized the heterogeneous pathway activities among different immune cell subpopulations after C. albicans infection. The CTLA-4 pathway was up-regulated in stimulated CD4⁺ and CD8⁺ T cells, while the PD-1 pathway showed high activity in stimulated plasmacytoid dendritic cell (pDC) and monocytes. Importantly, we found that immunosuppressive checkpoints HAVCR2 and LAG3 were only expressed in stimulated NK and CD8⁺ T cells, respectively. Their viabilities were validated by flow cytometry. We also identified three overexpressed genes (ISG20, LY6E, ISG15) across all stimulated cells. Also, two monocyte-specific overexpressed genes (SNX10, IDO1) were screened out in this study. Together, these results supplemented the landscape of immune checkpoints in fungal infection, which may serve as potential therapeutic targets for C. albicans infection. Moreover, the genes with the most relevant for C. albicans infection were identified in this study.

POS1135 MONOSODIUM URATE CRYSTALS REDUCE SCHWANN CELLS VIABILITY

Background:

The prevalence of peripheral neuropathy in patients with gout almostly reaches 25%[1]. Demyelination caused by Schwann cell (SCs) injury and apoptosis is the major pathological feature of peripheral[2]. None of study has focused on the effects of monosodium urate (MSU) crystals on SCs.

Objectives:

To assess the effect of MSU crystals on SCs.

Methods:

Mouse-derived Schwann cells (RSC96) are stimulated with different concentrations of MSU crystals (0mg/ml,0.25mg/ml,0.5mg/ml) and time (24h,48h,72h). The migration ability of Schwann cells is evaluated by acratch assay, the proliferation level is assessed by the cell counting kit-8 (CCK-8) assay, and the apoptosis rate is detected by flow cytometry.

Results:

The acratch assay showed that the migration ability of SCs was worsened, CCK-8 assay suggested that proliferation of SCs was reduced in a dose-dependent manner (P<0.05). According to the result of flow cytometry, the survival rate of SCs at 0.5mg/ml(78.60%±2.26%) was lower than that 0.25mg/ml(87.50%±0.95%)and 0mg/ml (98.80%±0.26%)(p<0.05) at 24h. When the stimulation time increased to 72h, the survival rate at 0.5mg/ml(47.90%±11.70%) dropped significantly, which was significantly different from the other two groups(p<0.05).

Conclusion:

MSU crystals can cause damage to Schwann cells. It may help to explain the reason of peripheral neuropathy in gout patients.

References:

[1]López-López, C.O., et al., Peripheral neuropathies in rheumatic diseases: More diverse and frequent than expected. A cross-sectional study. International journal of rheumatic diseases, 2020. 23(2): p. 226-232.

[2]Liu, Y., S. Shao and H. Guo, Schwann cells apoptosis is induced by high glucose in diabetic peripheral neuropathy. Life sciences, 2020. 248: p. 117459.

Figure 1.

Flow cytometry assays of RSC96 on MSU crystals at 72h

Disclosure of Interests:

None declared.

AB0050 A NOVEL METHOD FOR ISOLATION OF EXOSOMES FROM SYNOVIAL FLUID

Background:

Exosomes in synovial fluid (SF) has a close relationship with the pathogenesis of rheumatiod arthritis. As a complex biological fluid, SF presents challenges for exosomes isolation using standard methods, such as ExoquickTM kit and ultracentrifugation.

Objectives:

The study aims to compared the quality of exosomes separated by ExoquickTM kit (TM), ExoquickTM kit+ExoquickTC kit (TM-TC), ultracentrifugation (UC) and TM-TC+UC(TM-TC-UC) from SF.

Methods:

Exosomes was separated by TM, TM-TC, UC and TM-TC-UC respectively. The size and concentrations of exosomes were detected by high sensitivity flow cytometry for nanoparticle analysis. Total protein and RNA were extracted from exosomes. SDS-PAGE was used to detect the protein distribution of exosomes. Western blot was used to examine the level of albumin and exosomes marker (TSG101 and CD81).

Results:

There was no statistic difference in the diameters of exosomes separated by the four methods. The concentrations of exosomes in TM, TM-TC, TM-TC-UC and UC were (5.65±0.93), (3.02±1.19), (1.67±0.25) and (4.61±0.73) *109Particles/mL. The protein concentrations of exosomes separated by the four methods were consistent with the concentrations of exosomes. SDS-PAGE showed that the protein distribution of exosomes separated by the four methods were different. Low levels of albumin were detected in TM-TC and TM-TC-UC, while high levels of albumin in TM and UC. Total RNA concentrations from exosomes in TM-TC was higher than other groups.

Conclusion:

TM-TC can be used to obtain higher quality exosomes from SF for the study of exosome-enriched components.

References:

[1]Helwa I, et al, A Comparative Study of Serum Exosome Isolation Using Differential Ultracentrifugation and Three Commercial Reagents. PloS one, 2017. 12(1): p. e0170628-e0170628.

Figure 1.

A: SDS-PAGE showed the protein distribution of exosomes; B: the detection of albumin, TSG101 and CD81 by western blot.

Disclosure of Interests:

None declared

Divergent DNA methylation contributes to duplicated gene evolution and chilling response in tea plants

The tea plant (Camellia sinensis) is a thermophilic cash crop and contains a highly duplicated and repeat-rich genome. It is still unclear how DNA methylation regulates the evolution of duplicated genes and chilling stress in tea plants. We therefore generated a single-base-resolution DNA methylation map of tea plants under chilling stress. We found that, compared with other plants, the tea plant genome is highly methylated in all three sequence contexts, including CG, CHG and CHH (where H = A, T, or C), which is further proven to be correlated with its repeat content and genome size. We show that DNA methylation in the gene body negatively regulates the gene expression of tea plants, whereas non-CG methylation in the flanking region enables a positive regulation of gene expression. We demonstrate that transposable element-mediated methylation dynamics significantly drives the expression divergence of duplicated genes in tea plants. The DNA methylation and expression divergence of duplicated genes in the tea plant increases with evolutionary age and selective pressure. Moreover, we detect thousands of differentially methylated genes, some of which are functionally associated with chilling stress. We also experimentally reveal that DNA methyltransferase genes of tea plants are significantly downregulated, whereas demethylase genes are upregulated at the initial stage of chilling stress, which is in line with the significant loss of DNA methylation of three well-known cold-responsive genes at their promoter and gene body regions. Overall, our findings underscore the importance of DNA methylation regulation and offer new insights into duplicated gene evolution and chilling tolerance in tea plants.

AB0791 THE DIAGNOSIS VALUE OF SYNOVIAL FLUID LYMPHOCYTE IN GOUT PATIENTS

Background:

Synovial fluid cell counts have long been recognised to have utility in the diagnosis and management of arthritis. Few studies have explained the diagnosis value of synovial fluid cell counts in gout patients.

Objectives:

The study aims to investigate the diagnosis value of synovial fluid cell counts in gout patients.

Methods:

A total of 185 gout, 64 rheumatoid arthritis(RA), 26 axial spondyloarthritis(axSpA) and 24 osteoarthritis(OA) patients were included into the study. According to serum uric acid(sUA) level on attack, gout patients were divided into normal sUA gout patients and high sUA gout patients. The laboratory data was recorded and ROC curve was performed.

Results:

The synovial fluid WBC, PBMC, monocyte, PMN and neutrophil in gout patients were higher than OA patients (P<0.05). The synovial fluid PBMC and lymphocyte in gout patients were lower than RA and axSpA patients (P<0.05). Compared with RA, axSpA and OA patients, ROC curve showed that the AUC value of lymphocyte and sUA for gout were 0.728 and 0.881, which were higher than other variables. The optimal cut off value of lymphocyte for gout was 1.362, with sensitivity of 83.3% and specificity of 60.6%. The AUC value of lymphocyte and sUA for normal sUA gout patients were 0.694 and 0.643, which were higher than other variables. The optimal cut off value of lymphocyte for normal sUA gout patients was 1.362, with sensitivity of 81.6% and specificity of 60.6%.

Conclusion:

Synovial fluid cell counts of gout patients were different from RA, axSpA, and OA patients. Synovial fluid lymphocyte had a higher diagnosis value for gout.

References:

[1]Scanu A, Oliviero F, Ramonda R, et al. Cytokine levels in human synovial fluid during the different stages of acute gout: role of transforming growth factor β1 in the resolution phase. Ann Rheum Dis. 2012, 71(4): 621-4.

Table 1.

Basic characteristics of the participants

Gout(n=185)RA(n=64)axSpA (n=26)OA(n=24)P valueAge (years)48.58±15.5856.19±12.39*32.96±15.19*#69.63±12.43*#&<0.001Gender (male/female)176/911/5321/58/16<0.001WBC(×109/L)18.58±22.9422.24±20.8715.52±15.033.03±5.59*#&0.002PBMC(×109/L)1.85±1.993.68±2.43*3.85±3.34*0.74±1.01*#&<0.001Monocyte(×109/L)1.02±1.591.24±1.111.34±1.520.29±0.37*#&0.030PMN(×109/L)16.77±21.5118.57±19.3215.75±24.172.30±5.00*#&0.008Lymphocyte (×109/L)0.80±0.832.43±1.76*2.50±2.04*0.45±0.80#&<0.001Eosinophil (×109/L)1.32±3.750.56±0.930.11±0.170.49±1.850.098Neutrophil (×109/L)16.42±21.1618.82±20.8911.13±14.232.23±4.87*#0.003UA(μM)497.92±132.24299.31±97.91*351.81±118.93*333.38±75.19*<0.001ESR(mm/h)61.02±37.6882.42±32.87*68.12±36.2542.34±35.91*#&<0.001CRP(mg/L)56.52±45.6444.01±35.27*65.49±39.85#22.11±40.65*#&<0.001

*P<0.05 vs gout group, #P<0.05 vs RA group, &P<0.05 vs axSpA group

Disclosure of Interests:

None declared

POS0133 MONOSODIUM URATE CRYSTALS REDUCE HUMAN LIGAMENT CELLS VIABILITY THROUGH INCREASE OF ROS PRODUCTION

Background:

Ligament destruction is a frequent complication of gout and is strongly associated with tophi. Ligament fibroblasts are important cellular mediators of ligament remodeling. None of study has paid attention to the effects of monosodium urate (MSU) crystals on ligament fibroblasts.

Objectives:

The study aims to investigate the effects and mechanism of MSU crystals on ligament fibroblasts.

Methods:

MSU crystals were added to human ligament fibroblasts(HLFs) cultures or primary ligament cells cultures. Cell counting kit-8 (CCK-8) assay, cell migration assay, Annexin V-FITC/PI assay were conducted. Reactive Oxygen Species(ROS) was tested by ROS Assay Kit.

Results:

The higher concentrations of MSU crystals (0.5-1mg/mL) reduced the viability of HLFs or primary ligament cells after 24 h as assessed by CCK8 assays, with a further reduction in viability observed at the 48 h time point. When observed under light microscopy, HLFs cultured with MSU crystals (0.5mg/mL) appeared unhealthy with fewer cells present. The cell migration ability of HLFs was decreased significantly on MSU crystals (0.5mg/mL). According to the result of Annexin V-FITC/PI assay, the survival rate of HLFs on MSU crystals (0.5mg/mL) was lower than that of 0.25mg/ml and 0 mg/ml at 72h. ROS assay results showed that the production of ROS increased as the concentrations of MSU crystals increased.

Conclusion:

MSU crystals inhibit human ligament cells viability through the increase of ROS production. It may contribute to disordered ligament remodeling in gout patients with ligament destruction.

References:

[1]Ashika Chhana, et al. Monosodium urate crystals reduce osteocyte viability and indirectly promote a shift in osteocyte function towards a proinflammatory and proresorptive state. Arthritis Res Ther. 2018, 20(1): 208.

Figure 1.

MSU crystals reduce human ligament fibroblasts and primary human ligament cells viability over time. A: CCK-8 assay; B: Observation of HLFs morphology; C: Annexin V-FITC/PI assay.

Disclosure of Interests:

None declared

AB0642 CLINICAL CHARACTERISTICS AND FACTORS ASSOCIATED WITH BONE EROSION IN GOUT PATIENTS WITH TOPHI

Background:

Bone erosion is a frequent complication of gout patients with tophi and can lead to joint damage, deformity and musculoskeletal disability. Few studies have focused on clinical characteristics and factors associated with bone erosion in gout patients with tophi.

Objectives:

The aim of this study was to describe clinical characteristics of bone erosion in gout patients with tophi.

Methods:

Bone erosion was detected by X-ray. Gout patients with tophi were divided into bone erosion group and non bone erosion group. The clinical characteristics were recorded. Comparison of clinical characteristics and risk factors for bone erosion were analyzed between two groups. Multivariate logistic regression analysis was conducted.

Results:

A total of 171 gout patients with tophi were enrolled, 121 patients with bone erosion and 50 patients without bone erosion. Bone erosion group were older, with prolonged duration with gout and tophi, higher levels of serum creatinine, lower levels of glomerular filtration rate (GFR), C-reactive protein and BMI. In univariate regression analysis, age, gout duration, tophi duration, GFR were associated with bone erosion. In multivariable logistic regression analysis, tophi duration was independently associated with bone erosion.

Conclusion:

Gout patients with bone erosion present different clinical characteristics compared with those without bone erosion. Tophi duration was strongly associated with bone erosion in patients with gout.

Table 1.

Comparison of clinical characteristics between bone erosion patients and non bone erosion patients.

Non Bone erosionBone erosionP ValueN(male)50(47)121(118)0.255Age(year)45.82±14.1553.74±14.880.002BMI (kg/m2)26.01±4.5824.18±4.720.027WBC(109/mL)9.73±3.4011.37±13.260.404PLT(109/mL)329.86±96.22328.31±124.020.938HGB(g/L)86.58±63.78102.75±51.160.201ALT(U/L)37.74 ±26.5634.26±35.260.561sUA(umol/L)540.16±121.79539.00±121.460.962sCr(umol/L)111.47±25.26135.77±52.43<0.001GFR(ml/min/1.73m2)74.01±27.9456.68±22.840.003ESR(mm/h)61.78±37.3253.08±36.700.181CRP(mg/L)60.00±58.2636.45±42.620.014Gout duration (year)9.22±5.4612.63±7.590.001Tophi duration(year)3.77±3.226.64±4.810.001Hypertension, n17520.277Diabetes, n9120.143Smoking history, n20550.513Drinking history, n14370.737Ulceration, n10350.228

Disclosure of Interests:

None declared.

AB0645 CLINCAL CHARACTERISTICS OF GOUT PATIENTS WITH RENAL CYSTS

Background:

Gout is a crystal-related arthropathy caused by monosodium urate deposition, which is a common and treatable form of inflammatory arthritis and becoming more prevalent[1]. A few studies have found that gout patients have an increased prevalence of simple renal cysts[2, 3]. The relationship between gout and renal cysts is still insufficient.

Objectives:

Compare the difference between gout with renal cyst and without renal cyst.

Methods:

We retrospectively collected data on 200 gout patients. The data includes age, gender, uric acid, creatinine, glomerular filtration rate, 24-hour urine collection, and whether they have kidney stones, renal cysts, coronary heart disease, hypertension, and diabetes. Chi-square and exact Fisher’s tests were utilized, while continuous variables were assessed by Student’s t-test. A P value of less than 0.05 was considered statistically significant.

Results:

Of the 200 gout patients, 56 have kidney cysts(28%). In gout patients who had a renal cyst, were significantly older than patients without renal cysts (59.14 vs. 46.87, P = 0.000), more number of people suffering from coronary heart disease (7 vs. 5, P = 0.016). The glomerular filtration rate was lower (58.5 vs. 71.6, P = 0.000), with lower urinary creatinine, uric acid, and urinary potassium.

Conclusion:

Gout patients with and without simple renal cysts have significant differences in age, hypertension, cardiovascular disease, GFR, serum creatinine, urine creatinine, and urine potassium.

References:

[1]N. Dalbeth, T.R. Merriman, L.K. Stamp, Gout, Lancet 388(10055) (2016) 2039-2052.

[2]E.M. Hasegawa, R. Fuller, M.C. Chammas, F.M. de Mello, C. Goldenstein-Schainberg, Increased prevalence of simple renal cysts in patients with gout, Rheumatol Int 33(2) (2013) 413-6.

[3]Y. Han, M. Zhang, J. Lu, L. Zhang, J. Han, F. Zhao, H. Chen, Y. Bao, W. Jia, Hyperuricemia and overexcretion of uric acid increase the risk of simple renal cysts in type 2 diabetes, Sci Rep 7(1) (2017) 3802.

Table 1.

Clinical characteristics of gout patients

Renal cyst(n=56)Without Renal cyst(n=144)PDisease duration, (month)98.7(±64.1)91.2(±67.0)0.468Age, (year)59.14(±14.3)46.78(±15.9)0.000Gender, n(F/M)7/4911/1330.281Smoking history, n(%)18(32.1%)47(32.6%)0.946Drinking history, n(%)10(17.9%)32(22.2%)0.496Hypertension, n(%)31(55.3%)49(34.0%)0.006Diabetes, n(%)9(16.1%)15(10.4%)0.269CVDs, n(%)7(12.5%)5(3.4%)0.016Nephrolithiasis, n(%)14(25%)43(29.9%)0.494UA, (μmol/L)494.8(±158.0)544.3(±121.0)0.037Serum creatinine, (μmol/L)139.4(±57.2)116.5(±35.45)0.007GFR, (ml/L)58.5(±22.5)71.6(±22.3)0.000FEUA, (%)7.0(±3.2)6.0(±3.2)0.052Urine creatinine, (μmol/L)4687.09(±1832.9)5565.2(±2599.8)0.008Urine Uric acid, (μmol/L)1204.9(±772.0)1542.1(±1048.5)0.030Urine sodium, (mmol)132.1(±68.7)131.2(±76.6)0.939Urine potassium, (mmol)25.6(±12.5)31.8(±14.2)0.005

Disclosure of Interests:

None declared.

Feasibility of quantitative and volumetric enhancement measurement to assess tumor response in patients with breast cancer after early neoadjuvant chemotherapy

Objective

To evaluate the feasibility of quantitative enhancing lesion volume (ELV) for evaluating the responsiveness of breast cancer patients to early neoadjuvant chemotherapy (NAC) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

Methods

Seventy-five women with breast cancer underwent DCE-MRI before and after NAC. Lesions were assessed by ELV, response evaluation criteria in solid tumors 1.1 (RECIST 1.1), and total lesion volume (TLV). The diagnostic and pathological predictive performances of the methods were compared and color maps were compared with pathological results.

Results

ELV identified 29%, 67%, and 4% of cases with partial response, stable disease, and progressive disease, respectively. There was no significant difference in evaluation performances among the methods. The sensitivity, specificity, positive predictive value, negative predictive value (NPV), and accuracy of ELV for predicting pathologic response were 72%, 92%, 81.8%, 86.8%, and 85.3%, respectively, with the highest sensitivity, NPV, and accuracy of the three methods. The area under the receiver operating characteristic curve was also highest for ELV. Pre- and post-NAC color maps reflecting tumor activity were consistent with pathological necrosis.

Conclusions

ELV may help evaluate the responsiveness of breast cancer patients to NAC, and may provide a good tumor-response indicator through the ability to indicate tumor viability.

[Prognosis and related risk factors of acute respiratory distress syndrome in elder patients]

Objective: To study the risk factors associated with the hospital survival rate of elder patients with acute respiratory distress syndrome (ARDS) in Medical/Respiratory Intensive Care Units (MICUs/RICUs) by evaluating the prognosis, and therefore to provide insight into patient treatment strategy. Methods: Twenty MICUs/RICUs of 19 general hospitals in mainland China participated in the multicenter prospective cohort study carried out from Mar 1^st, 2016 to Feb 28^th, 2018. Patients who met the criteria of Berlin ARDS and older than 65 years were recruited. Baseline data, risk factors of ARDS, ventilator setup and prognosis data were collected from all patients. Univariant and multivariant regression analysis were conducted to analyze the factors associated with the prognosis. Results: 170 elder ARDS patients (age≥65 years) met the Berlin ARDS criteria, among whom 8.8% (15/170), 42.9% (73/170) and 48.2% (82/170) patients had mild, moderate and severe ARDS, respectively. The most common predisposing factor for elder ARDS was pneumonia, which was present in 134 patients (78.8%). 37.6% (64/170) patients were treated with noninvasive mechanical ventilation (NIV), but 43.8% (28/64) cases experienced treatment failure. 76.5% (130/170) patients were treated with invasive mechanical ventilation. All patients 80 years or older were given invasive mechanical ventilation. 51.8% (88/170) cases had complications of non-pulmonary organ failure. 61.8% (105/170) patients deceased during hospital stay. Multivariant logistic analysis showed that the independent risk factors for hospital survival rate in elder patients with ARDS were SOFA score (P=0.030, RR=0.725, 95% CI 0.543-0.969), oxygen index after 24 hours of ARDS diagnosis (P=0.030, RR=0.196, 95% CI 0.045-0.853), accumulated fluid balance within 7 days after diagnosis of ARDS (P=0.026, RR=1.000, 95% CI 1.000-1.000) and shock (P=0.034, RR=0.140, 95% CI 0.023-0.863). Conclusion: Among 20 ICUs, the high mortality rate of elder patients with ARDS was correlated with higher 24 hour SOFA score, lower 24 hour oxygen index after ARDS diagnosis, more positive fluid balance within 7 days and concomitant shock. The conservative fluid strategy within 7 days of ARDS diagnosis may benefit the elder ARDS patients.