Precise Regulation on the Bond Dissociation Energy of Exocyclic C-N Bonds in Various N-Heterocycle Electron Donors via Machine Learning

Heterocycles with saturated N atoms (HetSNs) are widely used electron donors in organic light-emitting diode (OLED) materials. Their relatively low bond dissociation energy (BDE) of exocyclic C-N bonds has been closely related to material intrinsic stability and even device lifetime. Thus, it is imperative to realize fast prediction and precise regulation of those C-N BDEs, which demands a deep understanding of the relationship between the molecular structure and BDE. Herein, via machine learning (ML), we rapidly and accurately predicted C-N BDEs in various HetSNs and found that five-membered HetSNs (5-HetSNs) have much higher BDEs than almost all 6-HetSNs, except emerging boron-N blocks. Thorough analysis disclosed that high aromaticity is the foremost factor accounting for the high BDE of 5-HetSNs, and introducing intramolecular hydrogen-bond or electron-withdrawing moieties could also increase BDE. Importantly, the ML models performed well in various realistic OLED materials, showing great potential in characterizing material intrinsic stability for high-throughput virtual-screening and material design efforts.

Enhanced hydrodechlorination of 4-chlorophenol through carboxymethylcellulose-modified Pd/Fe nanosuspension synthesized by one-step methods

Palladized iron (Pd/Fe) represents one of the most common modification strategies for nanoscale zero-valent iron (nZVI). Most studies prepared Pd/Fe by reducing iron salts and depositing Pd species on the surface of pre-synthesized nZVI, which can be called the two-step method. In this study, we proposed a one-step method to obtain Pd/Fe by the concurrent formation of Fe0 and Pd0 and investigated the effects of these two methods on 4-chlorophenol (4-CP) removal, with carboxymethylcellulose (CMC) coated as a surface modifier. Results indicated that the one-step method, not only streamlined the synthesis process, but also Pd/Fe-CMCone-step, synthesized by it, exhibited a higher 4-CP removal rate (97.9%) compared to the two-step method material Pd/Fe-CMCtwo-step (82.4%). Electrochemical analyses revealed that the enhanced activity of Pd/Fe-CMCone-step was attributed to its higher electron transfer efficiency and more available reactive species, active adsorbed hydrogen species (Hads*). Detection of intermediate products demonstrated that, under the influence of Pd/Fe-CMCone-step, the main route of 4-CP was through hydrodechlorination (HDC) to form phenol and H* was the main active specie, supported by EPR tests, quenching experiments and product analysis. Additionally, the effects of initial 4-CP concentration, initial pH, O2 concentration, anions such as Cl-, SO42-, HCO3-, and humic acid (HA) were also investigated. In conclusion, the results of this study suggest that Pd/Fe-CMCone-step, synthesized through the one-step method, is a convenient and efficient nZVI-modifying material suitable for the HDC of chlorinated organic compounds.

Metabolic habitat imaging with hemodynamic heterogeneity predicts individual progression-free survival in high-grade glioma

AIM

We design a feasibility study to obtain a set of metabolic-hemodynamic habitats for tackling tumor spatial metabolic patterns with hemodynamic information.

MATERIALS AND METHODS

Preoperative data from 69 high-grade gliomas (HGG) patients with subsequent histologic confirmation of HGG were prospectively collected (January 2016 to March 2020) after concurrent chemoradiotherapy (CCRT). Four vascular habitats were automatically segmented by multiparametric magnetic resonance imaging (MRI). The metabolic information, either at enhancing or edema tumor regions, was obtained by two neuroradiologists. The relative habitat volumes were used for weight estimation procedures for computing the coefficients of a linear regression model using weighted least squares (WLS) for metabolite semiquantifications (i.e. the Cho/NAA ratio and the Cho/Cr ratio) at vascular habitats. Multivariate Cox proportional hazard regression analyses are used to obtain the odds ratio (OR) and develop a nomogram using weighted estimators corresponding to each covariate derived from Cox regression coefficients.

RESULTS

There was a strongly correlation between perfusion indexes and the Cho/Cr ratio (rCBV, r=0.71) or Cho/NAA ratio (rCBV, r=0.66) at high-angiogenic enhancing tumor habitats (HAT) habitat. Compared isocitrate dehydrogenase (IDH) mutation to their wild type, the IDH wild type had significantly decreased Cho/Cr ratio (IDH mutation: Cho/Cr ratio = 2.44 ± 0.33, IDH wildtype: Cho/Cr ratio = 2.66 ± 0.36, p=0.02) and Cho/NAA ratio (IDH mutation: Cho/Cr ratio = 4.59 ± 0.61, IDH wildtype: Cho/Cr ratio = 4.99 ± 0.66, p=0.022) at the HAT. The C-index for the median progression-free survival (PFS) prediction was 0.769 for the Cho/NAA nomogram and 0.747 for the Cho/Cr nomogram through 1000 bootstrapping validation.

CONCLUSIONS

Our findings suggest that spatial metabolism combined with hemodynamic heterogeneity is associated with individual PFS to HGG patients post-CCRT.

Multimodel habitats constructed by perfusion and/or diffusion MRI predict isocitrate dehydrogenase mutation status and prognosis in high-grade gliomas

AIM

To determine whether tumour vascular and cellular heterogeneity of high-grade glioma (HGG) is predictive of isocitrate dehydrogenase (IDH) mutation status and overall survival (OS) by using tumour habitat-based analysis constructed by perfusion and/or diffusion magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Seventy-eight HGG patients that met the 2021 World Health Organization WHO Classification of Tumors of the Central Nervous System, 5th edition (WHO CNS5), were enrolled to predict IDH mutation status, of which 32 grade 4 patients with unmethylated O6-methylguanine-DNA methyltransferase (MGMT) promoter were enrolled for prognostic analysis. The deep-learning-based model nnU-Net and K-means clustering algorithm were applied to construct the Traditional Habitat, Vascular Habitat (VH), Cellular Density Habitat (DH), and their Combined Habitat (CH). Quantitative parameters were extracted and compared between IDH-mutant and IDH-wild-type patients, respectively, and the prediction potential was evaluated by receiver operating characteristic (ROC) curve analysis. OS was analysed using Kaplan-Meier survival analysis and the log-rank test.

RESULTS

Compared with IDH-mutants, median relative cerebral blood volume (rCBVmedian) values in the whole enhancing tumour (WET), VH1, VH3, CH1-4 habitats were significantly increased in IDH-wild-type HGGs (all p<0.05). Additionally, the accuracy of rCBVmedian values in CH1 outperformed other habitats in identifying IDH mutation status (p<0.001) at a cut-off value of 4.83 with AUC of 0.815. Kaplan-Meier survival analysis highlighted significant differences in OS between the populations dichotomised by the median of rCBVmedian in WET, VH1, CH1-3 habitats (all p<0.05).

CONCLUSIONS

The habitat imaging technique may improve the accuracy of predicting IDH mutation status and prognosis, and even provide a new direction for subsequent personalised precision treatment.

Analysis of the improvement effect of Astragalus extract on oxidative stress injury in viral myocarditis through STAT3/IL-6

The objective of this study was to investigate the improvement effect of Astragalus (AS) extract on oxidative stress (OS) and inflammatory response of myocarditis (MYO) cells through the STAT3/IL-6 axis. For this purpose, The MYO model cells prepared by intervening cardiomyocyte HL-1 with Coxsackievirus B3 (CVB3) were divided into four groups: model group, as well as high- (H-), medium- (M-) and low-dose (L-) AS groups treated by 80, 40, and 20 μg/mL AS, respectively. Conventionally cultured cells were set as the normal group. Cell multiplication and apoptosis, as well as levels of Myocardial injury markers (cTnT, BNP and CK), inflammatory cytokines (ICs; TNF-α, IL-1β and IL-6) and OS indices (SOD, GSH-Px and MDA), were measured. STAT3/IL-6 pathway expression was also observed. Results showed that the model group presented decreased cell multiplication than the normal group, but with increased myocardial injury, apoptosis rate, Caspase3 protein, ICs and OS reaction (P < 0.05); In the three AS-intervened groups, enhanced cell multiplication, while reduced myocardial injury, apoptosis rate, ICs and OS response were observed, especially in H-AS group (P < 0.05). Besides, STAT3 and IL-6 concentrations, statistically increased in the model group, were reduced by AS intervention (P < 0.05). Colivelin, a specific activator of STAT3, further aggravated the apoptosis, inflammatory reaction and OS response of MYO cells (P < 0.05), but its impacts on MYO cells could be reversed by AS. In conclusion, AS can ameliorate MYO, and its mechanism is related to the inhibition of cellular inflammatory response and OS response through the STAT3/IL-6 axis.

A comparison of different approaches for the analysis of 36Cl in graphite samples

This study compares different approaches for the quantification of the massic activity of 36Cl in graphite samples. All approaches consisted of a combustion step in combination with a trapping solution to collect the volatile elements. Two different resins were used to separate 36Cl from the matrix (CL resin and PS resin). Liquid scintillation counting (LSC), scintillation counting (SC) and tandem inductively coupled plasma mass spectrometry (ICP-MS/MS) were used to quantify 36Cl activity. The chemical yield in all approaches was determined by means of ion chromatography (IC). In addition, the methods were applied to a real activated graphite sample.

CTP-based estimated ischemic core: A comparative multicenter study between Olea and RAPID software

BACKGROUND AND PURPOSE

CTP is increasingly used to assess eligibility for endovascular therapy (EVT) in patients with large vessel occlusions (LVO). There remain variability and inconsistencies between software packages for estimation of ischemic core. We aimed to use heterogenous data from four stroke centers to perform a comparative analysis for CTP-estimated ischemic core between RAPID (iSchemaView) and Olea (Olea Medical).

METHODS

In this retrospective multicenter study, patients with anterior circulation LVO who underwent pretreatment CTP, successful EVT (defined TICI ≥ 2b), and follow-up MRI included. Automated CTP analysis was performed using Olea platform [rCBF < 25% and differential time-to-peak (dTTP)>5s] and RAPID (rCBF < 30%). The CTP estimated core volumes were compared against the final infarct volume (FIV) on post treatment MRI-DWI.

RESULTS

A total of 151 patients included. The CTP-estimated ischemic core volumes (mean ± SD) were 18.7 ± 18.9 mL on Olea and 10.5 ± 17.9 mL on RAPID significantly different (p < 0.01). The correlation between CTP estimated core and MRI final infarct volume was r = 0.38, p < 0.01 for RAPID and r = 0.39, p < 0.01 for Olea. Both software platforms demonstrated a strong correlation with each other (r = 0.864, p < 0.001). Both software overestimated the ischemic core volume above 70 mL in 4 patients (2.6%).

CONCLUSIONS

Substantial variation between Olea and RAPID CTP-estimated core volumes exists, though rates of overcalling of large core were low and identical. Both showed comparable core volume correlation to MRI infarct volume.

A Phase 2 Trial of Efficacy and Safety of Intraoperative Radiation Therapy for Locally Advanced Laryngocarcinoma

PURPOSE/OBJECTIVE(S)

For locally advanced laryngeal cancer (LAL), the local recurrence rate remains 19-40% after radical surgery with postoperative radiotherapy alone or with concurrent chemoradiotherapy in patients with unfavorable prognostic factors. We evaluate local control and acute toxicity of intraoperative radiation therapy (IORT) as a tumor bed boost for locally advanced laryngeal cancer in this prospective phase 2 trial.

MATERIALS/METHODS

This phase II clinical study in which a total of 63 LAL patients (T2N1-3/T3N0-3/T4N0-3) were selected and received IORT (T2: 8-10Gy, T3,4:12-15 Gy) as a tumor bed boost during radical surgery, then received external-beam radiation therapy (EBRT) at a total dose of 54-60Gy within 6 weeks after surgery, 5 times per week, 1.8-2Gy per time, 30 times in total. The median follow-up time was 20 months (7 -39 months). The primary outcome was the local control (LC) and 2 - year survival rate determined using the Kaplan-Meier method. This study is registered with ClinicalTrials.gov, NCT04278638.

RESULTS

A total of 63 patients consented to participate in the study; 59 males and 4 females, median age was 61 years (40-81 years), 14 patients had supraglottic LAL, 44 patients had glottic LAL and 5 patients had subglottic LAL. 10 patients showed high differentiation and 44 patients showed moderate differentiation and 9 patients showed low differentiation with laryngeal squamous cell carcinoma. 3 patients were in T2N1-2 stage, 40 patients in T3N0-2 stage, and 20 patients in T4N0-2 stage, 48 patients received total laryngectomy and 15 patients received hemilaryngectomy; 16 patients were lymph node-positive and 1 patient developed vascular tumor thrombus after surgery. After surgery combined with IORT and EBRT, the 1- and 2- year LC rates were 98.2% and 93.1 %, respectively, 2-year overall survival rate was 97.4%. Pharyngeal fistula was observed in 1 patient (1. 6 %) and wound infection in 3 patients (4.8%). Radiation Therapy Oncology Group (RTOG) grade 3 pain and RTOG grade 4 dyspnea were noted in one patient (1.6%) and 2 patients (3.2 %), respectively.

CONCLUSION

In summary, our prospective phase II trial proved that the addition of intraoperative radiotherapy as a tumor bed boost to postoperative radiotherapy provided local therapeutic benefit to patients with locally advanced laryngeal cancer. Our data support the safety of this combined therapy. Additional investigation is warranted to determine the role of intraoperative radiotherapy in the local treatment of locally advanced laryngeal cancer.

In vitro activities of contezolid (MRX-I) against drug-sensitive and drug-resistant Mycobacterium tuberculosis

A novel oxazolidinone for the treatment of Mycobacterium tuberculosis has been developed, but the activity of contezolid (MRX-I) still needs to be clarified. In this study, we isolated Mycobacterium tuberculosis from 48 clinical patients with pulmonary tuberculosis. Roche drug susceptibility tests identified drug-sensitive and 39 drug-resistant M. tuberculosis isolates. Drug susceptibility assays indicated that MRX-I exhibited anti-Mycobacterium tuberculosis activity against both drug-sensitive and drug-resistant isolates, with an advantage against drug-resistant isolates. The results also showed that the anti-Mycobacterium tuberculosis activity was comparable to that of linezolid. IMPORTANCE Currently, Mycobacterium tuberculosis has exhibited increased drug resistance, leading to ineffective drug treatment in many patients with tuberculosis. Among the anti-Mycobacterium tuberculosis drugs, oxazolidinones have been gradually developed. Contezolid (MRX-I) has been newly developed in China with advantages versus the first oxazolidinone antibiotic approved by the Food and Drug Administration for clinical use, but the anti-M. tuberculosis activity needs to be further clarified. In this study, in vitro activities of MRX-I against M. tuberculosis were tested. The drug susceptibility assays indicated that MRX-I exhibited anti-M. tuberculosis activity comparable to that of linezolid, with an advantage against drug-resistant isolates.

Room-Temperature, Multigram-Scale Synthesis and Conversion Mechanism of Highly Luminescent Lead Sulfide Quantum Dots

PbS quantum dots (QDs) are attractive near-infrared (NIR) materials, but traditional synthetic methods require inert atmosphere and/or high temperature. Herein we develop a facile, room-temperature synthetic route for in situ halide passivated PbS QDs through controllable reactions between lead halide, N,N'-diphenyl thiourea, and oleyamine (OLA) in toluene. Contrast experiments and theoretical calculations reveal that the OLA plays a bifunctional role as a mild base to initiate the formation of PbS monomers and as a dynamic ligand to control the crystallization of PbS QDs and further ligand exchange. The oleic acid-capped PbS QDs exhibit high photoluminescence quantum yields up to 45%. The scaled-up synthesis on multigram scales shows great batch-to-batch consistency. We further demonstrate high-power NIR light-emitting diodes using the PbS QDs as color converters, delivering NIR optical power of 9.2 mW at 160 mA. This work provides a simple and versatile synthetic route for high-quality PbS QDs and boosts the applications of NIR materials.

Relationship between dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus

OBJECTIVE

This study aimed to investigate the relationship between different dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus.

PATIENTS AND METHODS

This study was conducted based on the Chinese Chronic Disease and its Risk Factor Surveillance System. A multi-stage stratified sampling method was used to randomly select two districts (Henghualing District, Taiyuan City, and Yuzi District, Jinzhong City) and two counties (Huguan County, Changzhi City, and Jiang County, Yuncheng City) from the chronic disease surveillance sites in Shanxi Province to collect general information, dietary records, physical measurements, and laboratory tests. In total, 1,227 patients were enrolled according to the study criteria. Factor analysis was performed to construct six dietary patterns, and the relationship between dietary pattern scores and type 2 diabetic microvascular complications was analysed using binary logistic regression after correcting for confounders.

RESULTS

(1) Regarding the prevalence of type 2 diabetic microvascular complications and dietary characteristics, the prevalence of microvascular complications in patients with type 2 diabetes mellitus was 55.3% and was higher in urban than in rural areas. The prevalence of diabetic kidney disease (DKD), diabetic retinopathy, and diabetic peripheral neuropathy (DPN) were 21.4%, 12.7%, and 38.0%, respectively. (2) Six dietary patterns were constructed, namely, 'animal protein', 'coarse grains and plant protein', 'nuts and fruits', 'refined grains and vegetables', 'dairy', and 'added sugars', with factor contributions of 15.42%, 9.99%, 8.23%, 8.16%, 7.56%, and 7.28% respectively, explaining 56.64% of the total dietary variation. (3) After adjusting for confounding variables, the results of binary logistic regression indicated that patients in the highest quartile of dietary pattern scores for 'nuts and fruits' experienced a 43.3% lower risk of DKD compared to those in the lowest quartile [odds ratio (OR) = 0.567; 95% confidence interval (CI), 0.359-0.894; p < 0.001]. Similarly, patients in the highest quartile of dietary pattern scores for 'animal protein' had a 42.8% lower risk of DPN compared with those in the lowest quartile (OR = 0.572; 95% CI, 0.388-0.843; p < 0.05).

CONCLUSIONS

The results of this study suggest that in patients with type 2 diabetes mellitus, a 'nuts and fruits' dietary pattern reduces the risk of DKD and an 'animal protein' dietary pattern reduces the risk of DPN.

LTBI-negative close contacts of tuberculosis are more likely to develop the disease: enlightenment and lessons from a cluster outbreak

Background

Tuberculosis (TB) prevention and control among groups living together, such as students, workers, older adults in nursing homes, and prisoners, present many challenges due to their particular age and environmental factors, which can make them more susceptible to TB clusters with significant societal impact. This study aimed to evaluate a TB cluster outbreak epidemic in a university and provide suggestions for improving TB control strategies for groups living together.

Methods

Pulmonary TB screening and close-contact investigation were conducted using acid-fast staining, sputum culture, GeneXpert testing, tuberculin skin testing (TST), interferon-gamma release assay (IGRA), and chest computed tomography (CT). GraphPad Prism 9.5.1 was utilized for data analysis. Collected epidemic data were comprehensively analyzed by rate comparison.

Results

The TB cluster outbreak epidemic was identified with an index case confirmed positive. The initial screening was conducted on potential close contacts of the index case, and the TST's positive rate (diameter ≥ 5 mm) and strong positive rate (diameter ≥ 15 mm) among these close contacts were 65.60% (21/32) and 34.40% (11/32), respectively. Moreover, the latent TB infection (LTBI) rate (diameter ≥ 10 mm) was 43.75% (14/32), and the IGRA's positive rate was 9.30% (3/32). Chest CT scans did not reveal any abnormalities. Surprisingly, 5 of the close contacts developed active TB in the second screening, accompanied by changes from negative to positive TST and/or IGRA results, after 3 months of follow-up. Accordingly, we expanded the screening scope to include another 28 general contacts. We found that the positive rate (78.00%, 25/32), strong positive rate (50.00%, 16/32), and LTBI rate (62.50%, 20/32) of the 32 close contacts were significantly higher than those of the additional general contacts (28.00%, 8/28; 14.3%, 4/28; 25.00%, 7/28), as indicated by p < 0.05.

Conclusion

In the event of an epidemic TB outbreak, it is essential to rapidly identify the source of infection and initiate timely screening of close contacts. The initial screening should be focused on individuals without LTBI, who are at higher risk of developing TB. In purified protein derivative-negative individuals living in groups, additional vaccination or revaccination with Bacille Calmette-Guérin may help prevent cluster outbreaks of TB.

Longevity gene responsible for robust blue organic materials employing thermally activated delayed fluorescence

The 3^rd-Gen OLED materials employing thermally-activated delayed fluorescence (TADF) combine advantages of first two for high-efficiency and low-cost devices. Though urgently needed, blue TADF emitters have not met stability requirement for applications. It is essential to elucidate the degradation mechanism and identify the tailored descriptor for material stability and device lifetime. Here, via in-material chemistry, we demonstrate chemical degradation of TADF materials involves critical role of bond cleavage at triplet state rather than singlet, and disclose the difference between bond dissociation energy of fragile bonds and first triplet state energy (BDE-E_T1) is linearly correlated with logarithm of reported device lifetime for various blue TADF emitters. This significant quantitative correlation strongly reveals the degradation mechanism of TADF materials have general characteristic in essence and BDE-E_T1 could be the shared "longevity gene". Our findings provide a critical molecular descriptor for high-throughput-virtual-screening and rational design to unlock the full potential of TADF materials and devices.

Thermo-responsive polymer-modified metal-organic frameworks as soft-rigid enzyme-reactors for enhancement of enzymolysis efficiency using a controllable embedding protocol

Enzyme immobilization is a suitable strategy to promote biosensing, biocatalysis and the industrial applications of biomacromolecules. Although considerable efforts have been devoted to the construction of metal-organic frameworks (MOFs)-based porous nano-reactors, their enzymolysis efficiency cannot be tuned by varying the external conditions due to the fixed conformation of the encapsulated enzymes. In this work, a controllable embedding protocol was developed based on the concept of stimuli-responsive polymer modified MOFs. Using MOFs as a rigid template for thermo-responsive polymer modification and consequently utilizing the polymer-MOFs complexes for enzyme (glucose oxidase, horseradish peroxidase, trypsin, cytochrome c, glutaminase) immobilization, different porous nano-reactors were fabricated. Most importantly, the polymer on the MOF surface exhibited good ability to form a "soft nest" at high temperature for inducing the confinement effect and further improving the enzymolysis efficiencies of the nano-reactors 3.75-37.7-fold. Moreover, a colorimetric sensing method was developed to detect serum glucose with the proposed nano-reactors. This strategy is highly versatile and suitable for diverse rigid MOFs modified with stimuli-responsive soft-polymer-nests and enzymes.

[Comparison of intraoperative neurophysiological monitoring between patients with arthrogryposis multiplex congenita and adolescent idiopathic scoliosis]

Objective: To compare the intraoperative neurophysiological monitoring (IONM) results between patients with arthrogryposis multiplex congenita (AMC) and adolescent idiopathic scoliosis (AIS) and to analyze the influence of congenital spinal deformity on IONM in AMC patients, thus to evaluate the efficiency of IONM in AMC patients. Methods: A cross-sectional study. The clinical data of 19 AMC patients underwent correction surgery from July 2013 to January 2022 in Nanjing Drum Tower Hospital were retrospectively reviewed. There were 13 males and 6 females with a mean age of (15.2±5.6) years, and the average Cobb angle of main curve was 60.8°±27.7°. And 57 female AIS patients of similar age and curve type with the AMC patients during the same period were selected as the control group, with an average age of (14.6±4.4) years and a mean Cobb angle of 55.2°±14.2°. The latency and amplitude of samatosensory evoked potentials (SSEPs) and transcranial electric motor evoked potentials (TCeMEPs) were compared between the two groups. The difference in IONM data between AMC patients with and without congenital spinal deformity was also evaluated. Results: The success rates of SSEPs and TCeMEPs were 100% and 14/19 for AMC patients, 100% and 100% for AIS patients. The SSEPs-P40 latency, SSEPs-N50 latency, SSEPs-amplitude, TCeMEPs-latency, TCeMEPs-amplitude showed no significant difference between AMC patients and AIS patients (P>0.05 for all). The side-difference of TCeMEPs-amplitude showed an increasing trend in AMC patients when compared with that in AIS patients, but there was no statistical difference between the two groups [(147.0±185.6) μV vs (68.1±311.4) μV, P=0.198]. The SSEPs-amplitude value was (1.4±1.1) μV on concave side in AMC patients with congenital spinal deformity, and it was (2.6±1.2) μV on concave side in AMC patients without congenital spinal deformity (P=0.041). The SSEPs-amplitude value was (1.4±0.8) μV on convex side in AMC patients with congenital spinal deformity, and it was (2.6±1.3) μV on convex side in AMC patients without congenital spinal deformity (P=0.028). Conclusions: The values of SSEPs-P40 latency, SSEPs-N50 latency, SSEPs-amplitude, TCeMEPs-latency and TCeMEPs-amplitude are similar in AMC and AIS patients. The SSEPs-amplitude of AMC patients with congenital spinal deformity is lower than that of AMC patients without congenital spinal deformity.

Single-scan ultrafast laser inscription of waveguides in IG2 for type-I and type-II operation in the mid-infrared

We demonstrate, for the first time to our knowledge, single-scan ultrafast laser inscription and performance of mid-infrared waveguiding in IG2 chalcogenide glass in the type-I and type-II configurations. The waveguiding properties at 4550 nm are studied as a function of pulse energy, repetition rate, and additionally separation between the two inscribed tracks for type-II waveguides. Propagation losses of ∼1.2 dB/cm in a type-II waveguide and ∼2.1 dB/cm in a type-I waveguide have been demonstrated. For the latter type, there is an inverse relation between the refractive index contrast and the deposited surface energy density. Notably, type-I and type-II waveguiding have been observed at 4550 nm within and between the tracks of two-track structures. In addition, although type-II waveguiding has been observed in the near infrared (1064 nm) and mid infrared (4550 nm) in two-track structures, type-I waveguiding within each track has only been observed in the mid infrared.

Zinc oxide nanoparticles have biphasic roles on Mycobacterium-induced inflammation by activating autophagy and ferroptosis mechanisms in infected macrophages

The ability of zinc oxide nanoparticles (ZnONPs) to induce bacteriostasis in Mycobacterium tuberculosis (M. tb) and their roles in regulating the pathogenic activities of immune cells have been reported previously, but the specific mechanisms underlying these regulatory functions remain unclear. This work aimed to determine how ZnONPs play the antibacterial role against M. tb. In vitro activity assays were employed to determine the minimum inhibitory concentrations (MICs) of the ZnONPs against various strains of M. tb (BCG, H37Rv, and clinical susceptible MDR and XDR strains). The ZnONPs had MICs of 0.5-2 mg/L against all tested isolates. In addition, changes in the expression levels of autophagy and ferroptosis-related markers in BCG-infected macrophages exposed to ZnONPs were measured. BCG-infected mice that were administered ZnONPs were used to determine the ZnONPs functions in vivo. ZnONPs decreased the number of bacteria engulfed by the macrophages in a dose-dependent manner, while different doses of ZnONPs also affected inflammation in different directions. Although ZnONPs enhanced the BCG-induced autophagy of macrophages in a dose-dependent manner, only low doses of ZnONPs activated autophagy mechanisms by increasing the levels of pro-inflammatory factors. The ZnONPs also enhanced BCG-induced ferroptosis of macrophages at high doses. Co-administration of a ferroptosis inhibitor with the ZnONPs improved the anti-Mycobacterium activity of ZnONPs in an in vivo mouse model and alleviated acute lung injury caused by ZnONPs. Based on the above findings, we conclude that ZnONPs may act as potential antibacterial agents in future animal and clinical studies.

Fabrication of Dual-Stimuli-Responsive Polymer Vesicles for Regulation of Enzymolysis Efficiency in A Cascade Reaction

Enzymatic cascade reactions in confined microenvironments play important roles in cellular chemical transformation. Controlling enzymatic efficiency and eliminating substrate interference in cascade reactions is of great significance.  To this end, a vesicle composed of poly(styrene-maleic anhydride-N-isopropylacrylamide)(P(S-M-NIP)) and functionalized with 1,2-bis(10,12- tricosadiynoyl)-sn-glycero-3-phosphocholine (DC89PC) was designed herein. Based on the thermo-sensitive property of P(S-M-NIP) and the photo-responsive property of DC89PC, a serial of dual-stimuli-responsive nanoreactors was constructed via enzymes encapsulation to tune their enzymolysis efficiencies. A kinetics study of the glucose oxidase-encapsulated nanoreactor indicated that its enzymolysis velocity increased 2.1- and 1.6-fold under heating and the UV-light irradiation, respectively. Consequently, an enzymatic cascade reaction in the proposed enzyme reactor encapsulated with β-galactosidase and glucose oxidase was investigated. The results revealed a 2.9-fold enhancement in enzymolysis efficiency by changing the ambient temperature under UV irradiation.  The dual-stimuli-responsive polymer vesicles could also eliminate H2O2 interference during the enzymatic cascade reaction. The vesicles demonstrated potential for switch-membrane-permeability, while, the confined microenvironment played a key role in regulating the reactions upon the temperature change and the presence of UV light. Our synthetic multi-organelle-like system provides a new way to mimic the control of cascade reaction catalytic processes by programming the "open/close" sates of the nanocapsules.

The prenatal diagnostic indicators of placenta accreta spectrum disorders

Placenta accreta spectrum (PAS) disorders refers to a heterogeneous group of anomalies distinguished by abnormal adhesion or invasion of chorionic villi through the myometrium and uterine serosa. PAS frequently results in life-threatening complications, including postpartum hemorrhage and hysterotomy. The incidence of PAS has increased recently as a result of rising cesarean section rates. Consequently, prenatal screening for PAS is essential. Despite the need to increase specificity, ultrasound is still considered a primary adjunct. Given the dangers and adverse effects of PAS, it is necessary to identify pertinent markers and validate indicators to improve prenatal diagnosis. This article summarizes the predictors regarding biomarkers, ultrasound indicators, and magnetic resonance imaging (MRI) features. In addition, we discuss the effectiveness of joint diagnosis and the most recent research on PAS. In particular, we focus on (a) posterior placental implantation and (b) accreta after in vitro fertilization-embryo transfer, both of which have low diagnostic rates. At last, we graphically display the prenatal diagnostic indicators and each diagnostic performance.

Abnormal functional connectivity of the nucleus accumbens subregions mediates the association between anhedonia and major depressive disorder

BACKGROUND

The nucleus accumbens (Nac) is a crucial brain region in the pathophysiology of major depressive disorder (MDD) patients with anhedonia. However, the relationship between the functional imaging characteristics of Nac subregions and anhedonia remains unclear. Thus, this study aimed to investigate the role of resting-state functional connectivity (rsFC) of the Nac subregions between MDD and anhedonia.

METHODS

We performed resting-state functional magnetic resonance imaging (fMRI) to measure the rsFC of Nac subregions in 55 MDD patients and 30 healthy controls (HCs). A two-sample t test was performed to determine the brain regions with varying rsFC among Nac subregions between groups. Then, correlation analyses were carried out to investigate the relationships between the aberrant rsFC of Nac subregions and the severity of anhedonia. Furthermore, we constructed a mediation model to explain the role of the aberrant rsFC of Nac subregions between MDD and the severity of anhedonia.

RESULTS

Compared with the HC group, decreased rsFC of Nac subregions with regions of the prefrontal cortex, insula, lingual gyrus, and visual association cortex was observed in MDD patients. In the MDD group, the rsFC of the right Nac shell-like subregions with the middle frontal gyrus (MFG)/superior frontal gyrus (SFG) was correlated with consummatory anhedonia, and the rsFC of the Nac core-like subdivisions with the inferior frontal gyrus (IFG)/insula and lingual gyrus/visual association cortex was correlated with anticipatory anhedonia. More importantly, the functional alterations in the Nac subregions mediated the association between anhedonia and depression.

CONCLUSIONS

The present findings suggest that the functional alteration of the Nac subregions mediates the association between MDD and anhedonia, which provides evidence for the hypothesis that MDD patients have neurobiological underpinnings of reward systems that differ from those of HCs.

[Clinical study of serum human-βeta-defensin-1 level for evaluating short-term prognosis in patients with acute-on-chronic liver failure]

Objective: To evaluate the diagnostic value of serum human-βeta-defensin-1 level (HBD-1) for short-term (28-day) prognosis in patients with acute-on-chronic liver failure (ACLF). Methods: Fifty cases diagnosed with ACLF were selected. 20 cases with decompensated cirrhosis and 20 cases with compensated cirrhosis who were admitted at the same time were included. Age, gender, serum HBD-1 level, C-reactive protein (CRP), procalcitonin (PCT), neutrophil count/lymphocyte ratio (NLR), blood routine, coagulation function, liver function, kidney function, and other indicators from the three groups of patients were collected. Patients with ACLF were screened for indicators related to the short-term (28-day) prognosis. Patients were divided into an improvement group and a worsening group according to the 28-day disease outcome. The serum HBD-1 level and other above-mentioned indicators were compared between the two patient groups. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of serum HBD-1 levels for short-term prognosis in patients with ACLF. PCT, NLR, and prothrombin activity (PTA) application as a mono indicator and HBD-1 in combination with NLR, PCT, and PTA were compared to evaluate diagnostic efficacy for short-term prognosis in patients with ACLF. The intergroup mean of measurement data was determined using a t-test or analysis of variance. χ (2) test was used for comparison of count data. Spearman's rank correlation analysis was used for correlation analysis. Results: There was no statistically significant difference in age and gender among the three groups: ACLF, decompensated cirrhosis, and compensated cirrhosis (P > 0.05). The expression levels of serum HBD-1 in the ACLF group, decompensated cirrhosis group, and compensated cirrhosis group were (319.1 ± 44.4) ng/ml, (264.5 ± 46.5) ng/ml and (240.1 ± 35.4) ng/ml, respectively, while the ACLF group expression levels were significantly increased, with statistical significance (P < 0.01).The serum HBD-1 level was significantly higher in the ACLF worsening group (346.2 ± 43.6) ng/ml than that in the improvement group (308.5 ± 40.6) ng/ml, and the difference was statistically significant (P < 0.05). Correlation analysis showed that HBD-1, NLR, PCT, prothrombin time (PT), and international standardized ratio (INR) were negatively correlated with the 28-day disease outcome (improvement) of patients (P < 0.05). PTA was positively correlated with 28-day disease outcome (improvement) (P < 0.05). The area under the receiver operating characteristic curve (AUC) for evaluating HBD-1's diagnostic efficacy for short-term prognosis in patients with ACLF was 0.774, with a sensitivity of 0.750, a specificity of 0.786, and a cut-off point of 337.96 ng/ml. PCT, NLR, and PTA had greater diagnostic efficacy. HBD-1 combined with PTA had the highest diagnostic efficacy, with an AUC of 0.802, a sensitivity of 0.778, and a specificity of 0.786. The diagnostic efficacy of HBD-1+PCT, HBD-1+NLR and HBD-1, PCT, and NCR was superior to PTA mono. Conclusion: The serum HBD-1 level gradually increases with the aggravation of liver function injury and is negatively correlated with the short-term prognosis in patients with ACLF. Serum HBD-1 level has high sensitivity and specificity in predicting short-term prognosis in patients with ACLF, and its diagnostic efficacy is superior to that of PCT, NLR, and PTA. The combined application of HBD-1 and PTA has higher diagnostic efficacy; however, when the serum HBD-1 level is greater than 337.96ng/ml, it indicates poor prognosis in patients.

Dipeptide-Capped Copper Nanoparticles as Chiral Nanozymes for Colorimetric Enantioselective Recognition of 3,4-Dihydroxy-d,l-phenylalanine

In pharmaceutical and biomedical applications, it is imperative to identify chiral molecules. However, colorimetric sensing enantiomers relying on chiral nanozymes is still a major challenge in chirality recognition. Herein, we report a facile and simple strategy to prepare copper nanoparticles (CuNPs) using d-cysteine-d-histidine (DCDH), d-cysteine-l-histidine, and l-cysteine-d-histidine as the capping agents. All of these CuNPs exhibited peroxidase-mimicking activity in 3,3',5,5'-tetramethylbenzidine oxidation and presented chiral selectivity toward 3,4-dihydroxy-d,l-phenylalanine (d,l-DOPA). More importantly, DCDH-modified CuNPs (DCDH@CuNPs) showed higher peroxidase-mimicking catalytic activity in the presence of d-DOPA than l-DOPA. This demonstrates that in the stereoselective recognition CuNPs play the catalytic center role and chiral dipeptide ligands play the inducer role. The insights obtained from this study not only provide information to deeply understand the molecular principles of colorimetric chiral recognition upon CuNPs but also guide the design of dipeptide-based chiral nanozymes toward enantiomers.

Preparation of pH-responsive block copolymers for separation of cephalosporin antibiotics by open-tubular capillary electrochromatography

Stimuli-responsive block copolymers have exhibited their feasibility for drug delivery and analysis of biomolecules. However, study of the electrophoretic behavior of antibiotics by open tubular capillary electrochromatography (OT-CEC) based on smart block copolymers coatings is still a substantial challenge. Herein, we reported an OT-CEC protocol for analysis of cephalosporin antibiotics with pH-responsive block copolymers as coatings. By using the reversible addition-fragmentation chain-transfers radical polymerisation technique, the smart poly(styrene-maleic anhydride-acrylic acid) (P(St-MAn-AA)) was synthesized and subsequently chemical bonded onto the inner walls of amino-grafted capillaries. The pH induced changes in the stretch/curl states of P(St-MAn-AA) chains were used to generate an adjustable hydrophobic/hydrophilic interaction and hydrogen bonds between the polymer coatings and the analytes. The OT-CEC performance was evaluated by varying the monomer ratios, polymer coating amounts and layers, buffer concentrations and pH values. Baseline separation of the three-test antibiotics was achieved at pH 8.0. The proposed OT-CEC technique was further applied to the determination of rat serum antibiotics in the metabolic processes. The present work demonstrates an enhancement in antibiotics separation efficiency, and shows a great potential for the preparation of stimuli-responsive block copolymers coatings and in OT-CEC analysis of real samples in living bio-systems.

Investigation of a new approach for 36Cl determination in solid samples using plastic scintillators

This work reports a new approach for the determination of ³⁶Cl in radioactive waste samples from nuclear decommissioning, wherein novel plastic scintillator (PS) materials were used for the concentration of ³⁶Cl prior to the detection with scintillation counting. Different plastic scintillator (PS) materials were tested for their selective absorption and detection of ³⁶Cl activity in solid samples. PS microspheres (PSm), cross-linked PSm (CPSm) and PS resin have been investigated. PS resin was identified as the most suitable material for ³⁶Cl analysis. Pyrolysis and subsequent trapping of the volatile elements in a bubbler was used. The trapping solution was finally loaded onto a cartridge of the PS resin. Scintillation counting and ion chromatography were used to determine the activity concentration and the chemical recovery, respectively.

In Situ Monitoring of Intracellular ATP Variation Based on a Thermoregulated Polymer Nanocomposite

It is necessary to develop reliable chemiluminescence strategies for determination of intracellular adenosine triphosphate (ATP), which is vital in life science and clinical diagnosis. However, the current chemiluminescence methods based on firefly luciferase suffered from low delivery efficiency, unsatisfied targeting performance, and autohydrolysis in living biosystem. To circumvent these drawbacks, a thermoresponsive polymer nanocomposite modified with firefly luciferase and ATP aptamer (PFLNC@aptamer) was fabricated, which targeted ATP and determined the intracellular ATP levels via measuring the chemiluminescence signals at different temperatures. The PFLNC@aptamer exhibited capability for the enzymolysis efficiency regulation, increased 21.0% with temperature change from 37.0 to 25.0 °C. The ATP detection limit was 3.3 nM with a linear relationship from 10.0 nM to 0.1 mM. Moreover, the thermoresponsive nanocomposite could also effectively avoid the interference during delivering firefly luciferase into the living cells and effectively discriminate ATP via the immobilized ATP aptamer, which further confirmed its reliability for practical applications. It paves a specific avenue for effective intracellular ATP monitoring in fundamental and applied research.

Temperature modulating the peroxidase-mimic activity of poly(N-isopropyl acrylamide) protected gold nanoparticles for colorimetric detection of glutathione

More recently, loading polymer-ligand onto the surface of gold nanoparticles (AuNPs) as nanozymes has gained considerable attention. However, the efficient modulation of the nanozymes catalytic capability depending on external stimuli remains challenging. Herein, utilizing the thermo-responsive poly(N-isopropyl acrylamide) (PNIPAM) as a stabilizer and a reducing agent to make PNIPAM@AuNPs, we reported a straightforward and efficient protocol for modulating the peroxidase-mimic catalytic capability of PNIPAM@AuNPs in oxidation of 3,3',5,5'-tetramethyl benzidine (TMB)-H₂O₂ system by change of environmental temperature. More hydroxylradicals yielded and surface confinement effect induced by the coiled PNIPAM chains at high temperature could further significantly boost the nanozymes catalytic capability. In the presence of glutathione, the generation of oxidized TMB was inhibited and the absorption intensity of the reaction system decreased at 650 nm. The color-fadingproperty provided a highly selective assay for visualized and quantitative test of glutathione ranging 1.0 ～ 17.0 μM (R² = 0.993), the limit of detection was 0.8 μM. Moreover, the proposed method exhibited a promising application in analysis of rat serum glutathione following an intravenous injection. The strategy supplies a facile guideline for preparation of stimuli-responsive polymer@AuNPs with improved peroxidase-mimic catalytic activity toward application in real living bio-systems.

Fabrication of Polymer Membrane Enzyme Reactors with a Dual-Responsive Feature for Cascade Enzyme Reaction Regulation

Enzymes are known to drive biological processes efficiently and uniquely. However, the integration of multienzymes and immobilization technology to improve the stability of enzymes and boost the catalytic efficiency in cascade reactions by controlling the biocatalysis process in complex conditions via an external stimulus is still facing a significant challenge. Herein, we demonstrate a concept for cascade enzyme reaction regulation by controlling the catalytic efficiency step by step based on a dual-stimuli-responsive porous polymer membrane enzyme reactor (DPMER). Poly(styrene-maleicanhydride-acrylic acid-4-[(4-methacryloyloxy)phenylazo] benzoic acid) was designed for the fabrication of the DPMER with glutaminase and alanine aminotransferase as the model modified enzymes. Under UV light irradiation and by regulating the solution pH, the cascade enzyme reaction was carried out step by step. The polymer membrane surface demonstrated a configuration change while improving the enzymolysis efficiency of the DPMER. The enzymatic kinetics of the DPMER was investigated by a chiral capillary electrophoresis technique, and the cascade enzyme reaction regulation capability was evaluated. Under pH of 4.9 and 365 nm UV irradiation, the poly(4-[(4-methacryloyloxy)phenylazo] benzoic acid) and poly(acrylic acid) moieties changed from a "stretched state" to a "curled state" to form surface nanopores, which embedded the enzymes into the surface nanopores while causing the spatial confinement effect and enhancing the enzymolysis efficiency of the DPMER by 9.9-fold in comparison with the free enzymes. This concept provided a potential platform for cascade enzyme reaction regulation and highlighted the perspective of stimuli-responsive polymers.

Redox-Responsive Polymer Nanoreactors Based on Methionine Sulfoxide for Monitoring Cell Adhesion

Expanding the category of redox-responsive monomers suitable for enzymolysis efficiency regulation and application to living biosystems is a prerequisite to complementing the fabrication of stimuli-responsive polymer nanoreactors. However, the development of redox-responsive monomers is severely limited by chemical oxidation and low biocompatibility. This work presents a protocol for overcoming this problem by the self-assembly of redox-responsive polymer nanoreactors containing segments of water-soluble methionine sulfoxide residues and poly(styrene-co-maleic anhydride-l-methionine), and by immobilizing α-l-fucosidase into the nanoreactors. These nanoreactors demonstrate highly selective responses to a mild redox triggered by H₂O₂ from the initial state (V^O) to an oxidation state (V^O1), and are reduced by methionine sulfoxide reductase A to mold the V^O' state. It resulted in significantly enhanced enzymolysis efficiency and maximal reaction rates 8.1-fold (V^O) and 23.3-fold (V^O1) higher than those of the free enzyme. Moreover, cell adhesion was evaluated by the highly selective determination of l-fucose on cell surfaces. Using a combination of chemical oxidation and enzymatic reduction, this work achieves reiterative enzymolysis efficiency regulation of polymer nanoreactors, which has great potential for the construction of redox-responsive nanoreactors and for monitoring cell adhesion.

Poly(N,N-dimethylacrylamide)-stabilized gold nanoparticles as nanozymes with enhancement of catalytic activity for detection of lomefloxacin

Recently, polymer-protected gold nanoparticles (AuNPs) have attracted extensive attention due to their good catalytic activities. However, how to regulate their catalytic activities by changing the polymer chain morphologies or the interactions between the ligands and the analytes through external stimuli is still a great challenge. This study describes a simple synthesis of AuNPs capped by thermo-responsive poly(N,N-dimethylacrylamide) (PDMAM). In comparison with three kinds of PDMAMs@AuNPs, PDMAM-2@AuNPs exhibited better peroxidase-mimic ability via the catalytic oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) with hydrogen peroxide (H₂O₂) to generate oxidized TMB (oxTMB). Interestingly, its catalytic activity could be regulated by changing environmental temperature. Importantly, the addition of the antibiotic lomefloxacin endowed the PDMAM-2@AuNPs with enhancement in catalytic efficiency due to electrostatic interactions and the increased levels of reactive oxygen species. Based on this principle, a protocol for highly selective and sensitive monitoring of lomefloxacin has been constructed with the color change from pale blue to deep blue. The ultraviolet-visible absorbance of oxTMB at the wavelength of 650 nm showed a good linear relationship with antibiotic concentration in the range of 0.25-10.0 µM (R² = 0.990). The limit of detection was 0.1 µM. The practical application of the proposed protocol with the promoted peroxidase-mimic activity for the measurement of lomefloxacin in capsules was realized.

POS0811 CHARACTERISTICS OF INTESTINAL MICROBIOTA AND ITS RELATIONSHIP WITH LYMPHOCYTE SUBSETS AND CYTOKINES IN PATIENTS WITH VASCULITIS

Background

Vasculitis include a group of autoimmune inflammatory diseases with clinical heterogeneous characterized by inflammation of vascular wall, inflammation of perivascular tissues, and cell-like necrosis[1]. Disorder of gut microbiota, which plays a crucial role in regulating immune cells such as Th1, Th17 and Treg, is associated with other autoimmune diseases[2], and may also be involved in the pathogenesis of vasculitis.

Objectives

To investigate the changes of intestinal microbiota and its correlation with peripheral lymphocyte subsets and inflammatory factors levels in patients with vasculitis.

Methods

Combined with clinical manifestations and laboratory examination, 33 patients with vasculitis who met the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides[3] and 33 of age- and gender- matched healthy controls (HCs) were selected from the Second Hospital of Shanxi Medical University. The demographic characteristics, general laboratory indicators such as erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), levels of peripheral lymphocyte subpopulations and serum cytokines detected by modified flow cytometry. Fecal microbiota detected by 16S rRNA gene sequencing and compiled and processed using Qiime2 and OTU-profiling tables were collected and analyzed in this study.

Results

Compared with HCs, the richness and diversity of intestinal flora in patients with vasculitis tended to decrease with a statistically significant difference in β diversity (P = 0.025, Figure 1 A and B). More specifically, vasculitis patients had a lower frequency of Firmicutes while higher Proteobacteria and Bacteroidota at the phylum level (P < 0.001, Figure 1C). In vasculitis patients, the relative abundances of 23 bacteria differed from HCs at the genus level was all decreased, including Gemella, Anaeroglobus, Campylobacter, Fournierella, et al (P < 0.001, Figure 1D and E). More importantly, the relative abundance of Muribaculaceae were positively correlated with the absolute count of Th2 and the proportions of Th1 and CD4+T cells and negatively correlated with CRP and ESR, while relative abundance of [Eubacterium]_ventriosum were positively associated with the absolute number of Treg cells and negatively correlated with the percentages of Th2 and CD8+T cells (Figure 1F).

Figure 1.

Differences in α diversity (A), β diversity (B), phylum (C), genus (D), and microbial composition (E) between vasculitis patients and HC and correlation analysis between differential microflora and clinical data in patients with vasculitis (F).

Conclusion

Disturbance of intestinal flora, mainly manifested by decreased diversity and richness, may be involved in the occurrence and development of vasculitis by inducing disroders in lymphocyte subsets and cytokines. Consequently, further studies on the immune mechanisms and influencing factors of intestinal flora may provide new ideas for the diagnosis and treatment of the disease for vasculitis patients.

References

[1]Aierken X, Zhu Q, Wu T, et al. Increased Urinary CD163 Levels in Systemic Vasculitis with Renal Involvement[J]. Biomed Res Int, 2021, 2021: 6637235. DOI: 10.1155/2021/6637235.

[2]Zhang X, Zhang D, Jia H, et al. The oral and gut microbiomes are perturbed in rheumatoid arthritis and partly normalized after treatment[J]. Nat Med, 2015, 21(8): 895-905. DOI: 10.1038/nm.3914.

[3]Jennette JC, Falk RJ, Bacon PA, et al. 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides[J]. Arthritis Rheum, 2013, 65(1): 1-11. DOI: 10.1002/art.37715.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No.82001740).

Disclosure of Interests

None declared

AB0202 GUT MICROBIOTA DYSBIOSIS WERE CLOSELY CORRELATED WITH LYMPHOCYTE SUBSETS AND CYTOKINES IN PATIENTS WITH INFLAMMATORY ARTHRITIS

Background

Inflammatory arthritis includes a group of chronic conditions, particularly rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA)[1].Growing evidences link gut microbiota dysbiosis with the development of inflammatory arthritis[2].

Objectives

The aim of this study was to discover the characters of microbiota in inflammatory arthritis patients and compare the relationship between the microbiota and peripheral lymphocyte subsets and cytokines.

Methods

Fecal samples were collected from 73 arthritis patients (13 PsA, 30 AS, 30 RA patients) and 140 sex- and age-matched healthy controls (HCs). The gut microbiota was studied by sequencing the V3-V4 variable regions of bacterial 16S rRNA genes by the Illumina Miseq PE300 system. Peripheral lymphocyte subsets in these participants were assessed by flow cytometry. Measures of disease activity such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) were recorded. Alpha and Beta diversity was assessed using results from QIIME2 and gut microbiome profiles were compared using linear discriminant analysis (LDA) effect size (LEfSe). R (version 4.0.1) was used for comparative statistics, using pearson correlation analysis to assess the correlation between the relative abundance of genus in the sample and clinical parameters.

Results

Compared with HCs, the richness of gut microbiota (ACE and Chao 1) was significantly lower (p < 0.05) in arthritis patients, and bacterial diversity including Shannon and Simpson indices (p < 0.001) was also significant in arthritis decreased (Figure 1A). β-diversity analysis based on Bray-curtis distance revealed significant differences in microbial communities between arthritis and HCs (Figure 1B, r=0.098, p=0.001, ANOSIM). In addition, compared with HCs at the genus level, 9 bacterial groups were significantly different in PsA (p < 0.05), 19 bacterial groups in AS (p < 0.05), and 17 bacterial groups in RA(p < 0.05) (Figure 1C). There was a significant positive correlation between CD4+T and Prevotella(p<0.01), T and Prevotella(p<0.05), Blautia(p<0.05) as well as Megamonas(p<0.05), Th17 and Prevotella(p<0.01), CD8+T and Megamonas(p<0.01), Th1 and Megamonas(p<0.05), Prevotella(p<0.01),Coprococcus(p<0.05), B and Erysipelotricbaceae_UCG-003(p<0.01), and Erysipelotricbaceae_UCG-003(p<0.01), Anaerostipes(p<0.01), CRP and Fusobacterium(p<0.05) as well as Roseburia(p<0.05). There were negative correlations between T and Erysipelotricbaceae_UCG-003 (p<0.05),CD8+T and Fusobacterium(p<0.01), CD4+T and Fusobacterium(p<0.05), NK and Fusicatenibacter(p<0.05).

Conclusion

The gut microbiota of patients with inflammatory arthritis differs from HC and also varies among individual arthritis, which was closely related to lymphocyte subsets.

References

[1]Wu X. Innate Lymphocytes in Inflammatory Arthritis[J]. Front Immunol, 2020, 11: 565275.DOI: 10.3389/fimmu.2020.565275

[2]Breban M. Gut microbiota and inflammatory joint diseases[J]. Joint Bone Spine, 2016, 83(6): 645-649.DOI: 10.1016/j.jbspin.2016.04.005

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS0021 CHANGES OF GUT MICROBIOTA IN CONNECTIVE TISSUE DISEASE AND ITS RELATIONSHIP WITH LYMPHOCYTE SUBSETS AND CYTOKINES

Background

Connective tissue disease (CTD) is a group of autoimmune diseases characterized by the damage of connective tissue components in various parts of the body, which involved multiple organs and systems. Dysbiosis in the gut microbiome is associated with various autoimmune diseases such as CTD.

Objectives

To explore the characters of gut microbiota and their relationship with peripheral lymphocyte subsets and cytokines in patients with CTD.

Methods

Stool samples were collected from 63 CTD patients and 63 age- and sex-matched healthy controls(HCs). Microbial genomes were extracted for 16S rRNA gene sequencing. Gut microbiota characters (alpha diversity, beta diversity, and microbial composition) were analysed by R (version 4.0.1). Peripheral lymphocyte subsets were assessed by flow cytometry. Pearson correlation analysis was used to detect the correlation between the relative abundance of genus in the sample and the activity index; correlations with p < 0.05 were considered significant.

Results

Shannon and Simpson index revealed a decreased alpha diversity in CTD compared with that of HCs (p < 0.05), though not significantly difference in ACE and Chao1 parameters (p > 0.05, Figure 1A). Bray curtis distance-based beta-diversity analysis indicated significant differences in microbial communities between CTD and HCs (p = 0.0014, ANOSIM, Figure 1B). At the genus level, CTD patients had higher abundances of Terrisporobacter (p<0.01), Paraprevotella (p<0.01), CAG−352 (p<0.01), et al. but lower abundances of Streptococcus (p<0.01), Pseudomonas (p<0.01), Bacteroides(p<0.01), et al (Figure 1D). IgM was positively correlated with Lactococcus (p<0.05), Family_XIII_AD3011_group (p<0.05), Streptococcus (p<0.05). Th17 was positively correlated with Pseudomonas (p<0.01). Th2 was positively correlated with Christensenellaceae_R−7_group (p<0.001), UCG−010 (p<0.001) was positively correlated. Treg and Th2 were positively correlated with Christensenellaceae_R−7_group (p<0.01), UCG−010 (p<0.01). Treg was positively correlated with Lachnoclostridium (p<0.05) (Figure 1E).

Conclusion

Pattients with CTD had disbiosis of gut microbiota charaterized by impared diversity and abnomal composition,which was closely correlated with peripheral lymphocyte subsets.

References

[1]Laura Ghezzi,Claudia Cantoni,Gabriela V Pinget,et al.Targeting the gut to treat multiple sclerosis.J Clin Invest.2021 Jul 1;131(13):e143774. doi: 10.1172/JCI143774.

[2]Yoshihiko Tomofuji,Toshihiro Kishikawa,Yuichi Maeda,et al.Whole gut virome analysis of 476 Japanese revealed a link between phage and autoimmune disease.Ann Rheum Dis. 2022 Feb;81(2):278-288. doi: 10.1136/annrheumdis-2021-221267. Epub 2021 Dec 8.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS0745 GUT DYSBIOSIS ASSOCIATED WITH PERIPHERAL LYMPHOCYTES AND CYTOKINES IN PATIENTS WITH SJÖGREN’S SYNDROME

Background

Primary Sjögren’s syndrome (pSS) is a systemic autoimmune disease characterized by disorders of lymphocyte subpopulations with various cytokines and auto-antibodies1. Growing evidences suggest that gut microbiome dysbiosis may contribute to the development of pSS2.

Objectives

To investigate the alterations to the gut microbiome and the correlation with peripheral lymphocytes and serum cytokines as well as inflammatory factors in pSS patients.

Methods

A total of 101 pSS patients and 101 age- and sex- matched healthy controls (HCs) were enrolled in this study from The Second Hospital of Shanxi Medical University (Taiyuan, Shanxi, China). Patients fulfilled the 2019 ACR/EULAR classification criteria. We conducted 16S rRNA gene sequencing using fecal microbiota samples and analyzed the peripheral lymphocyte subsets by flow cytometry. Serum cytokines, erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), unstimulated and stimulated whole saliva (UWS and SWS) secretion rate was also collected, respectively. Sequence data were compiled and processed using Qiime2 and OTU-profiling tables were constructed. Correlations between different taxa and gut microbiome, as well as clinical variables, were calculated by Spearman’s rank test.

Results

Patients with pSS exhibited a significant reduction in the richness and diversity of gut microbiota compared with those of HCs (Figure 1A-B, p < 0.05). Detailly, at the phylum level, pSS patients had a lower frequency of Firmicutes while higher Proteobacteria (Figure 1C, p < 0.05). Compared with HCs, 11 species of flora were discovered to be distinctly different at the genus level (p < 0.05). Patients presented fewer Faecalibacterium and Roseburia but more Lactobacillus (Figure 1D, p < 0.05). Lactobacillus negatively correlated with T cells (r=-0.407), CD8+T (r=-0.417) and Th2 (r=-0.323). There was a significant positive correlation between Faecalibacterium and IL-2(r=0.312), IFN-γ(r=0.338), TNF-α levels(r=0.322) (Figure 1E, p < 0.05). As for clinical disease measures, IL-6 increases were in line with ESR and CRP, while IL-2 levels inversely related to CRP. Additional UWS secretion rate and SWS secretion rate had negative correlation with ESR (Figure 1F, p < 0.05).

Conclusion

The structural disorder of gut microbiota was distinct in pSS which were associated with peripheral lymphocyte subsets and cytokines. Disorders of gut microbiota and immune systems may contribute to the occurrence and development of pSS.

References

[1]Mariette X, Criswell LA. Primary Sjogren’s Syndrome. N Engl J Med 2018;378(10):931-39. doi: 10.1056/NEJMcp1702514

[2]Trujillo-Vargas CM, Schaefer L, Alam J, et al. The gut-eye-lacrimal gland-microbiome axis in Sjogren Syndrome. Ocul Surf 2020;18(2):335-44. doi: 10.1016/j.jtos.2019.10.006

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS0449 CHARACTERISTICS OF GUT MICROBIOTA AND ITS RELATIONSHIP WITH LYMPHOCYTE SUBSETS AND CYTOKINES IN PATIENTS WITH UNDIFFERENTIATED SPONDYLOARTHRITIS

Background

Gastrointestinal microbiota, particularly dysbiosis of gut microbiota composition have been correlated with the progression of autoimmune disorders, such as undifferentiated spondyloarthritis (USPA).

Objectives

This study aimed to identify the changed gut microbiota and its relationship with lymphocyte subsets and cytokines in USPA Patients.

Methods

A total of 210 participants were recruited in this study, comprising 105 USPA patients and 105 age and sex-matched healthy controls (HCs). Microbial genome was extracted from approximately 250mg fresh fecal samples from all participants using QIAamp PowerFecal DNA Kit (Qiagen). The V3-V4 variable regions of bacterial 16S rRNA genes were sequenced with the Illumina Miseq PE300 system. QIIME2 was used to process representative sequence clusters with a similarity cutoff of 100% (ASVs)1. Microbial diversity was estimated by the alpha diversity (observed, chao1, ACE, shannon, simpson, and ivsimpson) and beta diversity (bray distance). Biomarker species were identified based on STEMP between USPA and HC group. Correlations were analyzed with the Spearman rank correlation test.

Results

The alpha-diversity indices have no significant different between two groups (P >0.05, Figure 1A). Gut microbial community structure differed between USPA and HC, as revealed by ASV Bray–Curtis distances (P <0.05, Figure 1B). As for composition of gut microbiota, there were the increased levels of Escherichia_Shigella, Flavonifractor, Hungatella in the USPA group, and Lachnospirales, Roseburia, and Lachnospiraceae in HCs (Figure 1C). The relative abundance of Lachnospiraceae_UCG_001 and Enterobacter was negatively correlated with the absolute numbers of Th17 (P<0.05). Bifidobacterium was positively correlated with the absolute number of Th1 and Tregs (P<0.01, Figure 1D). The relative abundance of Fusobacterium, Incertae_Sedis, and Colidextribacter were negatively correlated with the absolute numbers of Il-10, IL-4, and IL-2 (P<0.05). Prevotella and Enterobacter were positively correlated with the absolute number of IL-6 and IL-4 respectively (P<0.05, Figure 1E). Bifidobacterium and Bilophila were neagtively correlated with the absolute number of NK cell (P<0.05, Figure 1F).

Figure 1.

(A) Comparison of alpha-diversity indexs between HC and USPA groups was shown using boxplot. (B) β diversity of the gut microbiome in USPA patients and HCs. Principal coordinate analysis plot generated from the bray distance analyse. (C) STEMP was used to detect difference in Flora according to USPA and HC. (D-F) Relationship between gut microbiota, and Lymphocyte subsets as well as cytokines. *P<0.05, **P<0.01.

Conclusion

Gut dysbiosis in USPA patients mainly characterized by reduced the diversity and impaired abundance of the intestinal flora, which was closely related to the disturbance of lymphocyte subpopulations and cytokines.

References

[1]Han L, Zhao K, Li Y, et al. A gut microbiota score predicting acute graft-versus-host disease following myeloablative allogeneic hematopoietic stem cell transplantation. Am J Transplant 2020;20(4):1014-27. doi: 10.1111/ajt.15654 [published Online First: 2019/10/13]

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared.

POS0330 DIFFERENCES IN GUT MICROBIOTA ASSOCIATED WITH LYMPHOCYTE SUBSETS, CYTOKINES AND DISEASE ACTIVITY IN ANKYLOSING SPONDYLITIS

Background

Ankylosing spondylitis (AS), a common chronic inflammatory disease, is a prototype of spondyloarthritis affecting sacroiliac joints and spine with or without peripheral arthritis and other systemic symptoms[1]. Environmental factors, especially microorganisms have been suggested to implicate with AS pathogenesis[2].

Objectives

Utilizing 16S rRNA genes sequencing on the feces of untreated AS patients and healthy controls (HCs), our study aimed to provide an in-depth understanding of AS gut microbiota and identifying a feasible diagnostic strategy for AS.

Methods

Fecal samples were collected from 62 AS patients and 62 age-and-gender- matched HCs. Microbial genome was extracted from approximately 250mg fresh fecal samples from all participants using QIAamp PowerFecal DNA Kit (Qiagen). The V3-V4 variable regions of bacterial 16S rRNA genes were sequenced with the Illumina Miseq PE300 system. QIIME2 based pipeline was used to process the raw sequence data. Alpha and beta diversities were assessed using result from QIIME2, and comparisons of gut microbiome profile were performed using linear discriminant analysis (LDA) effect size (LEfSe) to examine differences between AS and HCs. R (version 4. 0.1) was used for comparative statistics, and pearson’s correlation was used to assess the correlations between the relative abundances of bacterial genera and clinical parameters; correlations with p<0.05 were considered significant.

Results

AS for alpha-diversity, ACE and Chao1 indices were lower in AS compared with those HCs(Figure 1A, p<0.05), though no significant differences observed in Shannon and Simpson index. Bray curtis distance-based beta-diversity analysis revealed significant differences in the microbial community between AS and HCs (Figure 1B, p=0.003, ANOSIM). Fecal microbial communities in AS differed significantly from those in HCs, driven by higher abundances of Escherichia-Shigella, Turicibacter, Enterococcus, et al. and a lower abundance of Agathobacter, Roseburia, Eubacterium_eligens_group, et al (Figure 1C, p<0.05). There was a significant positive correlation between ESR and Klebsiella, Butyricicoccus, Roseburia, CRP and Faecalibacterium, Muribaculaceae, ASDAS-CRP score and Faecalibacterium, Ruminococcus, total lymphocyte cells and Agathobacter, Ruminococcus, T cell and Agathobacter, CD4+T cell and Agathobacter, B cell and Agathobacter, Streptococcus, Th1 and Prevotella, CAG−352, Th2 and Agathobacter, Th17 and Prevotella, Agathobacter, IL-2 and Agathobacter, IL-4 and Agathobacter, IL-6 and Lachnospiraceae_UCG−004, Muribaculaceae, IL-17 and Eubacterium_hallii_group, IFN-gama and Phascolarctobacterium.There were negative correlations between total lymphocytes and Escherichia−Shigella, CD4+T cell and Enterobacteriaceae, Th2 cell and Escherichia−Shigella, IL-10 and CAG−352, Ruminococcus (Figure 2, p<0.05).

Figure 1.

Feature of gut microbiota in AS patients and HCs. (A) Alpha-diversity assessed by richness (Chao1, ACE) and diversity (Shannon, Simpson), Median estimates compared across cohorts. (B) PCoA plot based on the Bray curtis distance of gut microbiota samples from AS patients vs. HC group(p=0.003, ANOSIM). (C) Panel demonstrated the average relative abundance of different genus in AS and HCs. (D) Distribution of gut microbiota at genus level.

Figure 2.

Correlations between the relative abundance of significantly different bacteria and clinical variables. *p<0.05, **p < 0.01, ***p <0 .001, ****p < 0.0001.

Conclusion

Human gut microbiome in patients with AS differed from that of the HCs. Characters of bacteria communities were associated with disease activity.

References

[1]Simone D, Al Mossawi M H, Bowness P. Progress in our understanding of the pathogenesis of ankylosing spondylitis [J]. Rheumatology (Oxford), 2018, 57(suppl_6): vi4-vi9.

[2]Zhou C, Zhao H, Xiao X Y, et al. Metagenomic profiling of the pro-inflammatory gut microbiota in ankylosing spondylitis [J]. J Autoimmun, 2020, 107(102360.

Acknowledgements

This project was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS1353 COMPOSITION AND ASSOCIATIONS OF THE GUT MICROBIOTA IN BECHET’S DISEASE WITH PERIPHERAL LYMPHOCYTE SUBSETS AND CYTOKINES

Background

Bechet’s disease (BD) is a chronic multisystemic vasculitis with genetic and abnormal immune response. Growing evidences suggests gut microbiota compositional alteration may have an association with immune dysfunction in patients with BD.

Objectives

This study aims to investigate the gut microbiota between BD and healthy controls (HCs) and analyse relevancy between bacterial and peripheral lymphocyte subsets and cytokines.

Methods

Fecal samples obtained from 22 BD patients and 22 normal-age and gender-matched HCs in this study. The gut microbiota were assessed with 16s rRNA sequencing and the flow cytometry was used to dectect peripheral lymphocyte subsets. C-reaction protein (CRP), Erythrocyte sedimentation rate (ESR), complement C3 and C4 were also assigned for disease activity measure. The edgeR package was used for differential abundance analysis. Difference of alpha diversity indices, bacterial abundances, and the F/B ratio were carried out using the Wilcoxon rank-sum test (R v.4.0.1). The differential abundance of flora and CRP, ESR, C3 and C4 between BD patients and HCs was assessed by pearson’s correlation analysis.

Results

As for alpha diversity, the Shannon (p < 0.05) and Simpsonance analysis. Difference of alpha diversity indices, bacterial abundances, and the F/B ratio were carried out using the Wilcoxon rank-sum test (R v.4.0.1). The differential abundamicrobial community structures between BD and HCs (R = 0.053, p = 0.051; Figure 1B). The gut microbiota compositions of BD differed form those of HCs (Figure 1C). Four species of flora distinctly difference were found in BD (p < 0.05; Figure 1D). There was significant positive correlations between Tregs and Verrucomicrobiota (p < 0.05), and Proteobacteria (p < 0.05), Th1 and Proteobacteria (p < 0.05), ESR and Verrucomicrobiota (p < 0.01), but negatives correlation between TNF-α and Desulfobactbiota (p < 0.05; Figure 1E).

Conclusion

Pattients with CTD had disbiosis of gut microbiota charaterized by impared diversity and abnomal composition, which was closely correlated with peripheral lymphocyte subsets and disease activity measures.

References

[1]Margaret Alexander, Qi Yan Ang, Renuka R Nayak, et al. Human gut bacterial metabolism drives Th17 activation and colitis. Cell Host Microbe. 2022 Jan 12;30(1):17-30.e9. doi: 10.1016/j.chom.2021.11.001. Epub 2021 Nov 24.

[2]Yi-Wen Tsai, Jia-Ling Dong, Yun-Jie Jian, et al. Gut Microbiota-Modulated Metabolomic Profiling Shapes the Etiology and Pathogenesis of Autoimmune Diseases. Microorganisms. 2021 Sep 10;9(9):1930. doi: 10.3390/microorganisms9091930.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

AB0492 INTESTINAL MICROBIOLOGICAL DISORDER CLOSELY ASSOCIATED WITH PERIPHERAL LYMPHOCYTE SUBSETS AND CYTOKINES IN SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by widespread inflammation and tissue damage in multiple organs[1]. Microbiome is one of environmental factors that has been suggested to contribute to the occurrence and development of SLE[2].

Objectives

This study aims to the understanding of the pathogenesis of SLE from the perspective of intestinal microorganisms and investigate the associations between flora and peripheral lymphocyte subpopulations and cytokines in SLE patients.

Methods

Fecal samples were collected from 96 patients with SLE, and 96 sex-and age-matched healthy controls (HCs). The gut microbiota were investigated via 16s rRNA sequencing and the peripheral T lymphocyte subsets of these participants were assessed by flow cytometry. Indicators of disease activity such as erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), complement C3 and C4 were recorded. Differential abundance analysis was carried out using the edgeR algorithm. The Wilcoxon rank-sum test was used to compare alpha diversity indices, bacterial abundances, and the F/B ratio between groups. R (version 4.0.1) was used for comparative statistics, and pearson’s correlation analysis was used to assess the correlations between the relative abundances of bacterial genera and serum levels of ESR, CRP, C3 and C4 in the samples; correlations with p < 0.05 were considered significant.

Results

The alpha estimators of richness (ACE and Chao 1) were significantly reduced in SLE feces samples compared with those of HCs (p < 0.0001). Bacterial diversity estimators, including the Shannon (p < 0.001) and Simpson’s (p < 0.01) indices, were also significantly lower in SLE (Figure 1A-D). The microbial community structures of the SLE and HCs could be separated by unweighted UnFrac-based principal coordinates analysis (PCoA) (R = 0.186, and p = 0.001; Figure 1E). Significant differences in gut microbiota composition between SLE and HCs were found using the edgeR algorithm. Compared with HCs, 24 species of flora were discovered to be distinctly different(p < 0.05). Moreover, there was a significant positive correlation between Tregs and Corynebacterium(p < 0.05), CD8+T and Corynebacterium (p < 0.05), CD4+T and Corynebacterium (p < 0.05), T and Corynebacterium (p < 0.05), Th1 and Escherichia−Shigella (p < 0.01), Th2 and Dielma (P<0.001) as well as Eubacterium eligens group (p < 0.05), NK and Faecalibacterium (p < 0.01). as well as Corynebacterium (p < 0.001), IL-6 and Coprococcus (p < 0.05), IL-10 and Eubacterium eligens group (p < 0.001) as well as Veillonella (p < 0.05). and Lachnospira (p < 0.01). As for clinical disease measures, there were positive correlations between CRP and Eubacterium ventriosum (p < 0.05). and Coprococcus (p < 0.05), C4 and the abundance of Corynebacterium (p < 0.05) (Figure 1F).

Conclusion

Patients with gut dysbiosis that mainly characterized by reduced the diversity and impaired abundance of the intestinal flora. Abnormality of T cell subsets and cytokines, especially the level of CD4+T, CD8+T, NK, Treg, Th, IL-6 and IL-10 cells contributes to the occurrence and progression of SLE, which may be related to the disturbance of gut microbiota. The discovery of the associated intestinal microbiota of SLE may provide a new idea for treatment.

References

[1]Fava A, Petri M. Systemic lupus erythematosus: diagnosis and clinical management. J Autoimmun. (2019) 96:1–13. 10.1016/j.jaut.2018.11.001

[2]He Z, Shao T, Li H, Xie Z, Wen C: Alterations of the gut microbiome in Chinese patients with systemic lupus erythematosus. Gut pathogens 2016, 8:64.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS0556 ALTERATION OF THE GUT MICROBIOTA IN CHINESE POPULATION WITH RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is an aggressive immune-mediated joint disease characterized by synovial proliferation and inflammation, cartilage destruction, and joint destruction. Growing evidences suggests a chronic inflammatory response induced by gut microbiome critically contribute to the development of rheumatoid arthritis.

Objectives

The aim of this study was to evaluate and quantify differences in the composition of gut microbiota in RA patients and investigate the associations between flora and clinical variables in RA patients.

Methods

Fecal samples from 145 RA patients and 145 age- and gender- matched healthy controls (HCs) were collected for bacterial 16S rRNA genes sequencing. The alpha-diversity, beta-diversity and the microbial composition (at the phylum and genus level) analysis of the gut microbiome were used to define the difference of gut microbiota profiles between RA patients and HCs. The peripheral lymphocytes of these patients were assessed by flow cytometry, and inflammatory biomarkers (ESR, CRP), auto-antibodies(ACPA, MCV) and cytokines measured by ELISA were recorded. Correlations between different taxa and clinical variables, were calculated by Spearman’s rank test.

Results

Consistent with trends observed for diversity, patients with RA had a lower richness compared with those of HCs (p < 0.01, Figure 1a), suggesting gut microbiome was markedly less diverse in composition in RA. Bray curtis distance-based beta diversity analysis revealed significant differences in the microbial community between RA and HCs (ANOSIM, R2=0.061, p=0.001, Figure 1b). Ten selected taxonomic biomarkers at different phylogenetic levels showed great discriminant ability, with Log10 LDA score > 4.0 (Figure 1e-g). Detailly, at the phylum level, RA patients had a lower frequency of Firmicutes while higher Proteobacteria. RA patients presented fewer Faecalibacterium but more Escherichia_Shigella at the genus level (Figure 1c-d). PICRUSt analysis found that in the KEGG pathways, the microbial gene functions related to Propanoate metabolism were higher in the fecal microbiome of RA patients (Figure 1h). Escherichia_Shigella positively correlated with ACPA antibodies (r=0.176, p < 0.05) and IL-4 (r=0.204, p < 0.05, Figure 1i), wheras Faecalibacterium as a probiotic showed no significant correlation with our clinical measures.

Figure 1.

Conclusion

Specific gut microbiota played an important role in the pathogenesis of RA, which may aid in the diagnosis or determination of the susceptibility of individuals to RA via detection of the gut microbiome.

References

[1]de Oliveira GLV, Leite AZ, Higuchi BS, et al. Intestinal dysbiosis and probiotic applications in autoimmune diseases. Immunology 2017;152(1):1-12. doi: 10.1111/imm.12765

[2]Chen J, Wright K, Davis JM, et al. An expansion of rare lineage intestinal microbes characterizes rheumatoid arthritis. Genome Med 2016;8(1):43. doi: 10.1186/s13073-016-0299-7

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared.

POS0143 COMPOSITION AND ASSOCIATIONS OF THE GUT MICROBIOTAWITH PERIPHERAL LYMPHOCYTE SUBSETS AND CYTOKINES IN IDIOPATHIC INFLAMMATORY MYOPATHIES

Background

The idiopathic inflammatory myopathies (IIM) are a group of acquired myopathies characterized by inflammatory lymphocytes infiltrates in muscle tissue1.Gut microbiota serves as a critical environmental component of autoimmune disease pathogenesis such as IIM2.

Objectives

This study sought to investigate the composition of gut microbiota and the relationship between microbiota structure and lymphocyte subpopulations and cytokines in IIM patients to recommend feasible intervention strategies.

Methods

Faecal samples were taken from 37 IIM patients and 37 age- and gender- matched healthy controls (HCs) in a sterile environment placed into the Second Hospital of Shanxi Medical University. Microbiome profiling was performed by sequencing of the V3-V4 variable regions of the 16S rRNA gene and the peripheral T lymphocyte subsets of these participants were assessed by flow cytometry. The clinical laboratory data such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and immunoglobulin were also determined. In terms of gut microbia, the diversity and richness was evaluated from two aspects: alpha diversity and beta diversity with the indices of ACE, Chao1, Shannon and Simpson. Analyses were conducted using R version 4.0.1. Pearson correlation was applied to assess the relationship between the relative abundances of bacterial genera and clinical parameters, and p < 0.05 was considered to be statistically significant.

Results

The α-diversity analysis of the richness (Chao1) and diversity (Shannon and Simpson) were reduced in IIM samples compared with those of HCs (Figure 1A, p < 0.05). Bray curtis distance-based beta diversity analysis revealed significant differences in the microbial community between IIM and HCs (Figure 1B, p = 0.001, ANOSIM). Detailly, at the genera level, IIM patients had a higher abundance of Enterococcus, Veillonella, Streptococcus, et al. and a lower abundance of Roseburia, Lachnospira, Klebsiella, et al(Figure 1D, p < 0.05). In IIM patients, Fusobacteriota correlated positively with the ratio of Th1 cells (Figure 1E, p < 0.01), and there was a significant positive correlation between Synergistota and B lymphocyte (Figure 1E, p < 0.01). Besides, Euryarchaeota and Cyanobacteria were both positively and significantly related to IL-6, IFN-γ and C-reactive protein (CRP) (Figure 1E, p < 0.001).

Conclusion

Richness and diversity of intestinal flora in IIM patients were impaired, which might participate in the pathogenesis of IIM by disturbing lymphocyte subpopulations and cytokines. Regulating intestinal flora and restoring homeostasis might become a critical therapeutic methods of IIM.

References

[1]Xu Y, Sun J, Wan K, et al. Multiparametric cardiovascular magnetic resonance characteristics and dynamic changes in myocardial and skeletal muscles in idiopathic inflammatory cardiomyopathy. J Cardiovasc Magn Reson 2020;22(1):22. doi: 10.1186/s12968-020-00616-0.

[2]Mariampillai K, Granger B, Amelin D, et al. Development of a New Classification System for Idiopathic Inflammatory Myopathies Based on Clinical Manifestations and Myositis-Specific Autoantibodies. JAMA Neurol 2018;75(12):1528-1537. doi: 10.1001/jamaneurol.2018.2598.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

AB0500 THE LEVEL OF PERIPHERAL BLOOD LYMPHOCYTE SUBSETS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS WITH RESPIRATORY TRACT INFECTION AND ITS CLINICAL SIGNIFICANCE

Background

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disorder. Infections are a most common cause of morbidity and mortality in this patient population[1] and at least 50% of patients with SLE are suffered with infections during the course of their disease [2]. Lymphocytes and Natural killer (NK) cells play an important role in the occurrence and development of SLE[3]. In this study, peripheral blood lymphocyte subsets were detected in these patients, providing reference for early diagnosis and treatment of SLE patients with respiratory tract infection.

Objectives

To analyze the detection level and clinical significance of peripheral blood lymphocyte subsets in patients with SLE with respiratory tract infection.

Methods

A total of 333 SLE patients with no recent infection, 95 SLE patients with respiratory tract infection, and 132 healthy individuals matched in age and sex were enrolled in the second Hospital of Shanxi Medical University from July 2014 to December 2016. The characteristics of lymphocyte subsets in the three groups were compared and receiver operating characteristic (ROC) curves were drawn to analyze the predictive value of lymphocyte subsets in SLE patients with respiratory tract infection.

Results

The counts of T, B, CD4 + T, CD8 + T, NK, Th1, Th2, Th17 and Tregs in SLE non-infection group and SLE infection group were [(1094.235 ± 574.495) / (702.781 ± 432.152), t= -7.169, P < 0.001], [(208.338 ± 210.448) / (177.55 ± 170.256), t = -1.306, P = 0.192], [(503.382 ± 303.498) / (304.075 ± 215.497), t = -7.168, P < 0.001], [(536.705 ± 344.218) / (358.034 ± 235.234), t = -5.802, P < 0.001], [(113.898 ± 101.48) / (61.768 ± 50.127), t = -6.831, P < 0.001], [(86.268 ± 89.081) / (47.92 ± 54.174), t = -3.367, P = 0.001], [(11.363 ± 9.834) / (6.628 ± 6.434), t = -3.622, P < 0.001], [(9.537 ± 10.12) / (5.346 ± 4.731), t = -3.646, P < 0.001], [(25.736 ± 27.013) / (20.78 ± 28.083), t =-1.037,P=0.301] (Figure 1).The above indexes in SLE infection group were lower than those in SLE non-infection groups. When lymphocyte subsets predict pulmonary infection in SLE, the AUC value of CD4 + count is the highest, and the cut-off is 387/ μ l(Table 1). The sensitivity and specificity of predicting SLE pulmonary infection were 75.8% and 38.6%(Figure 2).

Table 1.

Predictive value of peripheral blood lymphocyte subsets in SLE complicated with respiratory tract infection

IndicatorAUCP valueJordan indexcut-offSusceptibilitySpecificity(%)(%)B0.5690.04083.99500.1830.4210.238CD40.714<0.0010.3723870.7580.386CD80.682<0.0010.3254050.7260.401CD4+ T /CD8+ T0.5690.0410.0000.7850.5370.370NK0.687<0.0010.30982.50.7680.460

Conclusion

The absolute number of these subsets in infected SLE patients is significantly lower than that in uninfected patients, which indicates that the low absolute number of these cells can be used as an indicator of high infection risk in SLE patients. CD4 + T lymphocytes and NK cells in patients with respiratory tract infection are significantly lower, and can play a certain predictive value for SLE respiratory tract infection to a certain extent.

References

[1]Kedves M, Kosa F, Kunovszki P, Takacs P, Szabo MZ, et al. 2020. Large-scale mortality gap between SLE and control population is associated with increased infection-related mortality in lupus. Rheumatology (Oxford) 59:3443-51

[2]Wang J, Niu R, Jiang L, Wang Y, Shao X, et al. 2019. The diagnostic values of C-reactive protein and procalcitonin in identifying systemic lupus erythematosus infection and disease activity. Medicine (Baltimore) 98:e16798

[3]Luo Q, Kong Y, Fu B, Li X, Huang Q, et al. 2021. Increased TIM-3(+)PD-1(+) NK cells are associated with the disease activity and severity of systemic lupus erythematosus. Clin. Exp. Med.

Disclosure of Interests

None declared

POS0212 THE REDUCTION OF TURICIBACTER IN GUT MICROBIOTA ASSOCIATED WITH SJOGREN’S SYNDROME SECONDARY TO RHEUMATOID ARTHRITIS

Background

Secondary Sjogren’s syndrome(SS) is a common extra-articular manifestation of rheumatoid arthritis (RA)[1]. RA patients combined with SS have different outcomes from those without SS[2]. However, the studies investigated the characteristics of gut microbiota in patients with RA and SS is limited.

Objectives

To investigate the characteristics of gut microbiome and the associations between flora and peripheral lymphocyte subpopulations in RA patients with or without Sjogren’s syndrome.

Methods

A total of 326 samples from 145 RA patients without SS, 23 RA combined with SS patients(RA-SS) and 168 healthy controls (HCs) were recruit in this study from The Second Hospital of Shanxi Medical University (Taiyuan, Shanxi, China). The gut microbiota were investigated via 16s rRNA sequencing and the peripheral T lymphocyte subsets of these participants were assessed by flow cytometry. The Wilcoxon rank-sum test was used to compare alpha diversity indicesbetween groups. Differential abundance analysis was carried out the STAMP software. Spearman’s correlation analysis was used to assess the correlations between the relative abundances of bacterial genera and clinical meatures.

Results

Patients with RA and RA-SS exhibited a significant reduction in the richness and diversity of gut microbiota compared with those of HCs (Figure 1 A-B, p < 0.05), whereas there was no significant difference between RA and RA-SS patients. Principal co-ordinates analyses based on bray curtis distance suggested that these there microbiota states explained a definable proportion of observed variance in microbiota composition (ANOSIM R2 = 0.074, p < 0.001; Figure 1 C). Compared with HCs, 58 species of flora were discovered to be distinctly different in RA patients without SS at the genus level of which 6 species of flora unique to RA-SS patients were presented much fewer ([Eubacterium]_hallii_group, Anaerostipes, CAG-56, Fusobacterium, Turicibacter and Enterococcus). Among these RA-SS patients‘ unique species of flora, it seems that Turicibacter is the key species of flora, owing to whose has a positive correlation with most of lymphocytes such as T, B, CD4+T, CD8+T and NK cells suggesting a close association with intestinal immunity.(Figure 1 F-G,P<0.05)

Conclusion

RA patients with deficiency of Turicibacter in flora had higer occurrence of Sjögren’s syndrome sjogren’s syndrome complication, which was correlated with peripherial lymphocyte subpopulations and cytokines.

References

[1]Chen Y, Ma C, Liu L, He J, Zhu C, Zheng F, Dai W, Hong X, Liu D, Tang D et al: Analysis of gut microbiota and metabolites in patients with rheumatoid arthritis and identification of potential biomarkers. Aging 2021, 13(20):23689-23701.

[2]Brown LE, Frits ML, Iannaccone CK, Weinblatt ME, Shadick NA, Liao KP: Clinical characteristics of RA patients with secondary SS and association with joint damage. Rheumatology (Oxf) 2015, 54(5):816-820.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

AB0523 THE ENTEROTYPES OF THE GUT MICROBIOTA IN CHINESE POPULATION WITH AUTOIMMUNE DISEASE

Background

An increasing number of autoimmune disorders (AD) have been associated with microbial dysbiosis[1, 2]. However, this dysbiosis is difficult to characterize for individual patients owing to the high heterogeneity of the gut microbiota. Thus, researchers must find an accurate method of characterizing the AD gut microbiota that is meaningful to clinical diagnosis.

Objectives

The aim of this study was to investigate the enterotype characters of intestinal flora in AD and their associations with peripheral lymphocyte subpopulations and cytokines.

Methods

A total of 339 AD patients and 339 age- and sex- matched healthy controls (HCs) were enrolled in this study. Mathematical modeling using Dirichlet multinomial mixtures (DMM) was applied to describe the variability in the microbiome data and cluster samples into enterotypes. The peripheral lymphocyte subsets were detected by flow cytometry and the cytokines were assessed by ELISA. Differential abundance analysis was carried out the STAMP software. R (version 4.1.0) was used for comparative statistics, and spearman’s correlation analysis was used to assess the correlations between the relative abundances of bacterial genera and clinical variables.

Results

Laplace approximation of DMM suggested gut microbiota of AD patients and HCs both can be divided into two distinct enterotypes (Figure 1 A-B), and AD E1 and HC E1 were primarily dominated by Prevotella while AD E2 and HC E2 by Bacteroides. Interestingly, the Prevotella-enriched enterotype (AD E1 and HC E1) had a higher alpha diversity than The Bacteroides-enriched enterotype (AD E2 and HC E2). Patients with AD always had a lower richness and diversity compared with those of HCs in each enterotype (p< 0.001), suggesting gut microbiome was markedly less diverse in composition in AD. Bray curtis distance-based beta-diversity were also different (P<0.001, ANOSIM.R =0.23, Figure 1 C-H). Significant differences in gut microbiota composition at the genus level between AD patients and HCs were found using the STAMP software in each enterotype. Compared with HCs, 37 species in AD E1 patients and 40 species in AD E2 patients of flora were discovered to be distinctly different. In the co-upregulated flora of both enterotypes, Lactobacillus was inversely associated with a variety of lymphocytes such as T, CD4+T, NK, Th2, Th17, Treg cells(P<0.05), and positive correlation with IL-10 and IFN-γ(P<0.05,Figure 1 I). However, in the co-downregulated floras Coprococcus had a positive correlation with B, NK and Treg cells, and anaerostipes had a negativate corrleation with IL-2 and IL-4(P<0.05,Figure 1 J).

Conclusion

There were both two enterotypes in patients and HCs with autoimmune disease, E2 exhibited a loss of Prevotella but a growth of Bacteroides, while E1 presented the opposite results, which were closely correlated with peripheral lymphocyte subsets and cytokines.

References

[1]Levy M, Thaiss CA, Zeevi D, Dohnalová L, Zilberman-Schapira G, Mahdi JA, David E, Savidor A, Korem T, Herzig Y et al: Microbiota-Modulated Metabolites Shape the Intestinal Microenvironment by Regulating NLRP6 Inflammasome Signaling. Cell 2015, 163(6):1428-1443.

[2]Belkaid Y, Hand TW: Role of the microbiota in immunity and inflammation. Cell 2014, 157(1):121-141.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS1153 CHARACTERISTICS OF GUT MICROBIOME AND THEIR ASSOCIATIONS WITH PERIPHERAL LYMPHOCYTE SUBPOPULATIONS AND CYTOKINES IN RHEUMATOID ARTHRITIS PATIENTS COMPLICATED WITH OSTEOPOROSIS

Background

Osteoporosis(OP) is one of the major comorbidities of rheumatoid arthritis(RA) which is associated with immune disorders[1]. The gut microbiota has been highlighted to be an important environmental factor to influence immune system in maintaining bone health and regulating bone remodeling[2]. However, the alterations of intestinal flora and its relationship with immune system in RA patients with OP are unclear.

Objectives

To investigate the characteristics of gut microbiome as well as the associations between flora and peripheral lymphocyte subpopulations and cytokines in rheumatoid arthritis patients complicated with osteoporosis.

Methods

Total 28 RA patients were divided into 14 RA-non-OP and 14 gender- and age-matched RA-OP groups according to their bone mineral density (BMD) and the history of fragility fracture. Gut microbiota of participants were investigated by 16s rRNA and peripheral lymphocyte subsets and cytokines were assessed via flow cytometry. Indicators like erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), anti-cyclic citrullinated peptide antibody (ACPA) and anti-mutated citrullinated vimentin (MCV) antibody were recorded meanwhile. Alpha diversity (ACE, Chao1, Simpson, Shannon) and beta diversity indices were analyzed using QIIME2. Biomarker species were recognized based on STEMP. Spearman analysis was adopted for correlation of two variables. All P-values reported herein were two-tailed and P-value<0.05 was taken as statistically significant.

Results

The alpha-diversity have no significant difference between RA-non-OP and RA-OP groups (P >0.05, Figure 1A). The community structure of microflora differed between two groups (P <0.05, Figure 1B). As for the composition of intestinal flora at genus level, Faecalibacterium, Proteus, Catenibacterium, Enterobacter and Erysipelatoclostridium in RA-OP group as well as Lachnospiraceae_ND3007_group, Parasutterella, Megasphaera, Tyzzerella, UCG-005, Clostridium_sensu_stricto_1, UCG-002, Lachnospiraceae_NK4A136_group, Christensenellaceae_R-7_group, Prevotella, Parabacteroides in RA-non-OP group were significantly increased (Figure 1C). There were positive correlations between Lachnospiraceae_NK4A136_group and the level of T, Th1 and Th17 cells, but negative relevance with ESR, CRP and IL-10 (P <0.05). The relative abundance of Faecalibacterium was negatively correlated with IL-2, IL-4, TNF-α and positively with MCV (P <0.05). Clostridium_sensu_stricto_1 and Lachnospiraceae_ND3007_group were negatively correlated with ACPA and MCV respectively as well as IL-2 (P <0.05, Figure 1D-E).

Conclusion

Abnormality of immune system may contribute directly or indirectly to OP in RA, which may be related to the disturbance of gut microbiota.

References

[1]Horta-Baas G, Romero-Figueroa MDS, Montiel-Jarquín AJ, et al. Intestinal Dysbiosis and Rheumatoid Arthritis: A Link between Gut Microbiota and the Pathogenesis of Rheumatoid Arthritis. J Immunol Res. 2017;2017:4835189.

[2]Raterman HG, Bultink IE, Lems WF. Osteoporosis in patients with rheumatoid arthritis: an update in epidemiology, pathogenesis, and fracture prevention. Expert Opin Pharmacother. 2020 Oct;21(14):1725-1737.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

AB0844 Characterizing Gut Microbial Enterotypes in undifferentiated spondyloarthritis

Background

The presence of dysbiosis in the gut microbiome is responsible for the initiation of autoinflammatory and autoimmune diseases. However, such dysbiosis is difficult to characterize in sweeping generalization owing to the high dimensional complexity of the gut microbiota.

Objectives

This study designed to characterize the gut microbial enterotype in patients with undifferentiated spondyloarthritis (USpA) from lower dimensionality and describe the dysbiosis.

Methods

The Fecal samples of 105 patients were diagnosed with USpA and gender- and age- matched 105 healthy controls (HC) were included in the intestinal microbiota composition analyses via Illumina sequencing of bacterial 16S rRNA genes. Microbiota-derived clustering was performed using Dirichlet multinomial mixtures (DMM) modeling. To identify discriminative features in abundance between enterotypes, the Linear Discriminant Analysis Effect Size (LEfSe) algorithm was used with the online interface Galaxy (Log10 LDA score > 4.0). The phyloseq R package to compute alpha diversity (ACE, Chao1, Shannon and Simpson indices), beta diversity (Bray-Curtis dissimilarity) and the microbial composition (at the genus level) to describe the richness and diversity of the microbiota between two enterotypes.

Results

As showed in Figure 1A and C, by evaluating the Laplace approximation to the negative log mode, 2 distinctly enterotypes were identified in the USpA and HC microbiota dataset. LEfSe Analysis indicated the distinctive abundant microbial clades between the 2 enterotypes (LDA score >4) in both the USpA and HC group respectively. At the genus level, Faecalibacterium and Prevotella was the driving genus of enterotype 1 and Bacteroides contributed to enterotype 2 (Figure 1B, D). The alpha-diversity and beta diversity between the distinctive enterotypes was highly significantly different (P < 0.01, Figure 1E, F). Distinct bacterial profiles were also observed in enterotype 1 and 2 (Figure 1G). Interestingly, no significant differences were found between USpA patients and HC for the corresponding same intestinal type. This may be because USpA was at a comparatively early stage of spondyloarthritis (SpA).

Conclusion

Two significantly distinct bacterial microbiota structures existed in the USpA patients which was consistent with the general healthy population.

References

[1]Belkaid Y, Hand TW: Role of the microbiota in immunity and inflammation. Cell 2014, 157(1):121-141.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

OP0087 INTEGRATED SYSTEMS ANALYSIS OF THE GUT MICROBIOTA PHENOTYPES IN THE RHEUMATOID ARTHRITIS

Background

Patients with rheumatoid arthritis (RA) displays extreme dysbiosis in microbiota. However, such dysbiosis is difficult to characterize owing to the high dimensional complexity of the gut microbiota1,2.

Objectives

The aim of this study was to discover the enterotype characters of intestinal flora in RA.

Methods

Fecal samples from 145 RA patients were collected for bacterial 16S rRNA genes sequencing. Mathematical modeling using Dirichlet multinomial mixtures (DMM) was applied to describe the variability in the microbiome data and cluster samples into enterotypes. The alpha-diversity, beta-diversity and the microbial composition analysis of the gut microbiome were used to define the difference of gut microbiota profiles between different enterotypes. The nonredundant taxonomic biomarkers for each enterotype were selected by using LEfSe. Inflammatory biomarkers (ESR, CRP), auto-antibodies(ACPA, MCV), peripheral lymphocytes subsets and cytokines were analyzed in our cohort using the Kruskal-Wallis test.

Results

Laplace approximation of DMM indicated two significantly distinct bacterial microbiota structures (RAE1 and RA E2) existed in the dataset (Figure 1a). Principal co-ordinates analyses confirmed that these two microbiota states explained a reasonable proportion of observed variance in microbiota composition(ANOSIM R2 = 0.267, p = 0.001; Figure 1b), with distinct bacterial genus distribution of in each enterotype (Figure 1c). RA E1 were primarily dominated by Prevotella while RA E2 by Bacteroides. Interestingly, Chao1, ACE, Shannon and Simpson revealed a higher alpha diversity in Prevotella-enriched enterotype (p< 0.001, Figure 1d). Fourteen selected taxonomic biomarkers at different phylogenetic levels showed great discriminant ability, with Log10 LDA score > 4.0 (Figure 1e-g). Further, inflammatory biomarkers (ESR, CRP) and auto-antibodies(ACPA, MCV) as well as the number of T, B and CD4+T, Th1, Th2, Th17, and Treg were consistent in RA E1 and RA E2 (p > 0.05, Figure 2h). But CD8+T were significantly higher in RA E2 than in RA E2 (p < 0.05).

Conclusion

Despite RA gut microbiota being of different dysbiosis, two patterns of dysbiosis, designated as RA-enterotypes, were predominant among the RA patient cohort. RA E2 exhibited a loss of Prevotella but a growth of Bacteroides, while RA E1 presented the opposite results.

References

[1]Arumugam M, Raes J, Pelletier E, et al. Enterotypes of the human gut microbiome. Nature 2011;473(7346):174-80. doi: 10.1038/nature09944

[2]Costea PI, Hildebrand F, Arumugam M, et al. Enterotypes in the landscape of gut microbial community composition. Nat Microbiol 2018;3(1):8-16. doi: 10.1038/s41564-017-0072-8

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared.

Polymer-capped gold nanoparticles as nanozymes with improved catalytic activity for the monitoring of serum ciprofloxacin

More recently, gold nanoparticle (AuNP)-based nanozymes have become one of the burgeoning research hot topics. However, few studies have focused on these AuNP-nanozymes with polymers as ligands. A significant challenge is to reveal their catalytic mechanism and to improve their catalytic activity by changing the structures of the polymers. In this study, polyacrylamide (PAM) with different chain lengths was synthesized and used as the ligand to prepare PAM@AuNPs. The resultant nanozymes exhibited good peroxidase-like activity for catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H₂O₂). In particular, due to the electrostatic interaction between the negatively charged PAM@AuNPs and the positively charged drug, the addition of ciprofloxacin in the oxidation system induced the aggregation of PAM@AuNPs and produced more amount of reactive oxygen species, which greatly promoted the catalytic activity of PAM@AuNPs. Inspired by the attractive property, a highly selective and sensitive colorimetric assay for the monitoring of ciprofloxacin was created. A good linear relationship between the UV-Vis absorption intensity of PAM@AuNPs-TMB-H₂O₂ at 650 nm wavelength and the ciprofloxacin concentration was observed ranging from 1.0 μM to 12.0 μM (R² = 0.998), providing the detection limit of 0.5 μM. The ciprofloxacin metabolism was further studied in rats. It reveals great potential of polymer protected AuNP-nanozymes in practical drug analysis.