The transcription factor SbHY5 mediates light to promote aluminum tolerance by activating SbMATE and SbSTOP1s expression

Aluminum (Al) toxicity is a major factor limiting crop yields in acid soils. Sweet sorghum (Sorghum bicolor L.) is a high-efficient energy crop widely grown in tropical and subtropical regions of the world, where acid soil is common and Al toxicity is widespread. Here, we characterized a transcription factor SbHY5 in sweet sorghum, which mediated light to promote plant Al stress adaptation. The expression of SbHY5 was induced by Al stress and increasing light intensity. The overexpression of SbHY5 improved Al tolerance in transgenic plants, which was associated with increased citrate secretion and reduced Al content in roots. Meanwhile, SbHY5 was found to localize to the nucleus and displayed transcriptional activity. SbHY5 directly activated the expression of SbMATE, indicating that a HY5-MATE-dependent citrate secretion pathway is involved in Al tolerance in plants. SbSTOP1 was reported as a key transcription factor, regulating several Al tolerance genes. Here, inspiringly, we found that SbHY5 directly promoted the transcription of SbSTOP1, implying the existence of HY5-STOP1-Al tolerance genes-mediated regulatory pathways. Besides, SbHY5 positively regulated its own transcription. Our findings revealed a novel regulatory network in which a light signaling factor, SbHY5, confers Al tolerance in plants by modulating the expression of Al stress response genes.

TFAM Modulates Cardiomyocytes Pyroptosis Induced by Ionizing Radiation through mtDNA/TLR9/NF-kB Pathway

PURPOSE/OBJECTIVE(S)

Mitochondrial transcription factor A (TFAM) is a pivotal factor for regulating mitochondrial DNA (mtDNA) replication, transcription and biogenesis. Previous studies have reported that cytosolic mtDNA stress can lead to cardiomyocytes pyroptosis, which is characterized by inflammasome formation. In this study, we attempted to investigate the mechanism of TFAM regulate cardiomyocytes pyroptosis induced by ionizing radiation.

MATERIALS/METHODS

The peripheral blood serum of patients with esophageal cancer before and after definitive chemoradiotherapy was collected for Luminex multiplex cytokine assays. C57BL/6 mice were irradiated with the whole heart using small animal radiation research platform (SARRP) to construct a radiation-induced myocardial damage (RIMD) mouse model, and the ventricular function was evaluated using 9.4T Bruker magnetic resonance (MR) scanner. The function changes of cardiomyocytes exposed to radiation were observed in vitro and in vivo after knocking out GSDMD. Furthermore, the changes of mitochondrial function, the levels of cytosolic mtDNA, and the protein levels of NF-kB and pyroptosis pathway in irradiated cardiomyocytes were analyzed by knockdown and overexpression of TFAM in vitro and in vivo.

RESULTS

By multifactor cytokine assays we found that pyroptosis related IL-1β and IL-18 were significantly increased in patients with high mean heart dose (MHD) after radiotherapy, while those with low MHD were not significantly increased after radiotherapy. Next, we successfully constructed the RIMD mouse model using a single heart irradiation of 20 Gy. We found that the gene expression of pyroptosis pathway was significantly up-regulated after cardiac irradiation by myocardial tissue transcriptomic sequencing. Compared with wild-type (WT) mice, cardiac systolic function of Gsdmd-/- mice was significantly improved at 1, 2, 6, 12, and 24 weeks after heart irradiation. In vitro, we also demonstrated increased viability of irradiated cardiomyocytes by knocking out GSDMD. In vitro and in vivo experiments confirmed the expression of TFAM decreased after radiation. By overexpression of TFAM, we found that irradiated cardiomyocytes showed improved mitochondrial function, decreased release of mtDNA into cytoplasm through mitochondrial permeability transition pores (mPTPs), decreased binding of cytosolic mtDNA to TLR9, and decreased expression of NF-kB and pyroptosis pathway proteins. Dual luciferase gene reporter assays and Chromatin immunoprecipitation (CHIP) assay confirmed that p65 could bind the NLRP3 promoter region. In addition, we found that ventricular function deteriorated and improved in mice with knockdown and overexpression of TFAM through adeno-associated virus serotype 9 (AAV9), respectively.

CONCLUSION

Our study indicated that TFAM regulate irradiated cardiomyocytes pyroptosis through mtDNA/TLR9/NF-kB pathway. We provide a novel mechanism of RIMD, revealing an underappreciated intervention target for RIMD.

Safety and Efficacy Analysis of Patients with Extensive-Stage Small Cell Lung Cancer (ES-SCLC) Treated with SHR-1316 Plus Chemotherapy and Sequential Chest Radiotherapy as First-Line Therapy from a Phase II Trial

PURPOSE/OBJECTIVE(S)

CAPSTONE-1, a phase 3 trial, showed that SHR-1316 (PD-L1 antibody) combined with standard first-line chemotherapy could prolong overall survival (OS) in patients (pts) with ES-SCLC. The CREST trial reported consolidative thoracic radiotherapy (TRT) of 30 Gy in 10 fractions provided a 10% 2-year OS benefit and more intensive TRT should be investigated in ES-SCLC. In the era of immunotherapy, the role of TRT also needs further exploration. Therefore, we designed this clinical trial to investigate the efficacy and safety of SHR-1316 plus first-line chemotherapy followed by TRT combined with SHR-1316.

MATERIALS/METHODS

Key inclusion criteria were pts aged 18-75 years, with previously untreated histologically or cytologically confirmed ES-SCLC, and an ECOG performance status of 0-1. Eligible pts would receive 4∼6 cycles of SHR-1316 (20mg/kg, D1, q3w) combined with EP/EC (etoposide, 100mg/m2, D1-5, q3w and cisplatin, 75mg/m², D1-3, q3w or carboplatin, AUC = 5, D1, q3w), followed by SHR-1316 combined with TRT (≥3 Gy*10 f or ≥2 Gy*25 f, involved-field irradiation), and then the maintenance therapy with SHR-1316 until disease progression or intolerable adverse events (AEs). The main endpoints included ORR, PFS and safety.

RESULTS

From October 2020 to January 2023, 33 pts received SHR-1316 and sequential consolidative TRT. Among them, 19 pts received high-dose TRT (>3 Gy*10 f or ≥2 Gy*25 f) and 14 pts received low-dose TRT (≤3 Gy*10 f or<2 Gy*25 f). The median age was 62 (range: 38-73). Most pts were male (28, 84.8%), former smokers (22, 66.7%) with an ECOG performance status 1 (32, 97%). Ten (30.3%) pts were diagnosed with brain metastasis and 10 (30.3%) pts had liver metastasis at baseline. At the data cutoff date, 9 pts remained on treatment, the average number of treatment cycles was 9.2. 33 pts had at least one 1 post-treatment tumor assessment. The confirmed ORR and DCR were 90.9% (30/33) and 100% (33/33) in all pts, were 89.5% (17/19) and 100% (19/19) in high-dose TRT group, and were 92.9% (13/14) and 100% (14/14) in low-dose TRT group. The median PFS was 10.2(CI: 5.8∼14.7) months in all pts, was 7 (CI: 3.8∼10.2) months in high-dose TRT group and 10.4 (CI: 8.4∼12.3) months in low-dose TRT group. AEs occurred in 27 (81.8%) pts and grade 3 or 4 AEs occurred in 20 (60.6%) pts. The most common grade 3 or 4 AEs included neutropenia (15, 45.5%), leukopenia (8, 24.2%), lymphocytopenia (5, 15.2%), pneumonia (3, 9.1%), anemia (3, 9.1%) and thrombocytopenia (2, 6.1%).

CONCLUSION

SHR-1316 plus chemotherapy and sequential TRT as first-line therapy for ES-SCLC showed promising efficacy and acceptable safety. There is no significant difference between high-dose and low-dose TRT groups in terms of safety and efficacy according to current data.

Performance Evaluation in Automatic Plan Generation for Ethos Intelligent Optimization Engine

PURPOSE/OBJECTIVE(S)

To evaluate the automatic optimization performance and clinical feasibility of the Intelligent Optimization Engine (IOE) of Ethos online adaptive radiotherapy platform.

MATERIALS/METHODS

Eleven patients with cervical cancer treated with Halcyon accelerator were retrospectively selected. All the patients manually planned with four full arc volume rotating intensity modulated radiotherapy (VMAT) (Manual-4Arc), and the prescription dose was 45 Gy/25F. All patient images and structures were imported into Ethos simulator, and clinical goals were added appropriately based on clinical requirements. The target coverage was normalized to 95%. 7F, 9F, 12F IMRT plans and 2Arc, 3Arc VMAT plans were automatically generated by IOE. Dosimetric index comparisons were made among the Manual-4Arc plans and five group IOE generated plan to evaluate the automatic optimization performance of IOE.

RESULTS

In terms of hot dose area, for PTV, D1% of IMRT-12F plans was the lowest, and there were significant differences between IMRT-12F plans and Manual-4Arc plans (46.936 ± 0.241 vs 48.639 ± 2.395, p = 0.004); In terms of target coverage, the CTVs of all groups meet clinical requirements. Although the Ethos online adaptive plans have been normalized during planning, the PTV coverage is slightly insufficient (12F: 94.913 ± 0.154; 9F: 94.585 ± 1.148). For OARs close to target, such as bladder, V30Gy, V40Gy and Dmean have significant differences among the six group plans. The order of bladder dose is basically followed by IMRT-12F

CONCLUSION

The plans automatically generated by Ethos IOE can achieve similar performance as the manual plan, and the automatically generated IMRT-12F and 9F plans are preferred for clinical use.

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Affiliation(s)

Z Wang Department of Radiation Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
B Yang Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
X Meng Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
Y Liang Department of Radiation Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
T Pang Department of Radiation Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
J Qiu Department of Radiation Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China

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Dose DIBH Really Reduce the Subclinical Cardiac Acute Injury? Analysis of Clinical Real World from Our Institute

PURPOSE/OBJECTIVE(S)

The study is aim to investigate whether Deep-inspirational breath-hold (DIBH), compared with free breathing (FB), could provide a short-term cardiac benefit in patients with early left breast cancer after breast-conserving surgery combined whole breast radiotherapy.

MATERIALS/METHODS

A total of 78 patients with early stage left breast cancer treated with radiotherapy between 2021-2022 after breast-conserving surgery were enrolled. Among them, 32 cases were treated with DIBH technique and 46 cases were treated with free breathing. Patients with previous cardiac disease such as coronary artery disease were excluded. We performed myocardial enzymes, ECG, and ECHO in all patients within 2 weeks before, during, and 6 months after radiotherapy. The results of the two groups were compared using nonparametric tests and chi-square tests, and P < 0.05 indicated statistical significance. Where subclinical acute cardiac injury was defined as new above-normal myocardial enzymes and/or electrocardiographic ST-T or T-wave changes and/or ECHO abnormalities after the start of radiotherapy.

RESULTS

The median follow-up of patients was 6 months and the mean age of patients was 52.3 years for FB and 44.9 years for DIBH. There were no significant differences in staging, molecular subtype, chemotherapy and endocrine therapy history. The proportion of subclinical acute cardiac injury was smaller in the DIBH group compared to the FB group (DIBH = 31/46 and FB = 28/32, p = 0.042). The most sensitive of the subclinical acute cardiac injury events were detected by myocardial enzymes rising, with cTnI (p = 0.034) and NT-proBNP (p = 0.023) appearing significantly lower in the DIBH patients during radiotherapy. The difference of cTnI between 2 groups at 6 months after radiotherapy became non-significant. In contrast, CK-MB was higher in DIBH compared with FB only 6 months after radiotherapy (p = 0.006). The differences in ECG and ECHO were not significant between the two groups.

CONCLUSION

After breast-conserving surgery combined with radiotherapy for left early breast cancer, DIBH compared to FB reduces the proportion of acute subclinical cardiac injury that occurs with the most sensitive changes in myocardial enzymes. Subsequent studies will explore the relationship between the short-term subclinical injury and irradiated dose, as well as long term cardiac injury.

The Predictive Value of Changes in Basal Myocardial F-18 Fluorodeoxyglucose Uptake for Cardiotoxicity in Locally Advanced Esophageal Cancer Patients Receiving Definitive Radiotherapy

PURPOSE/OBJECTIVE(S)

To investigate the predictive value of changes in myocardial 18F-FDG uptake for major adverse cardiac events (MACEs) in locally advanced esophageal cancer patients receiving definitive radiotherapy.

MATERIALS/METHODS

Between August 2012 and January 2018, 400 patients with stage II-III esophageal cancer receiving definitive radiotherapy at two institutions were divided into the training (n = 240) and external validation cohorts (n = 160). All patients underwent FDG-PET imaging within 1 week before treatment and 3 months after treatment. Myocardium delineation was performed by Carimas software (version 2.10) based on the AHA 17-segment model. When contouring the left ventricle, the myocardium was automatically divided into basal (segments 1-6), middle (segments 7-12), and apical (segments 13-16) regions, and the mean dose and FDG uptake parameters of each region were obtained by Carimas. Our primary endpoint was MACEs. Patient clinicopathologic factors, dosimetric parameters for the whole heart and cardiac substructures, and myocardial changes within the three regions on 18F-FDG PET were utilized to seek the best predictive models for cardiotoxicity. To avoid multicollinearity between dose-volume histogram (DVH) parameters, we selected the variables with the lowest Akaike Information Criterion (AIC) value from the DVH parameters of the same cardiac structure for the actual modeling procedure. Competing risk analysis and Cox regressions analysis were performed. The predictive performance of the models was evaluated using the area under the receiver operating characteristic curve (AUC) and Brier score.

RESULTS

At a median follow-up interval of 78 months, 28 patients (11.7%) developed MACEs. The basal region of the myocardium received the highest radiation dose, followed by the middle and the apex region. The basal myocardial SUVmax and SUVmean significantly increased after radiotherapy while the apical and middle myocardial SUVmax and SUVmean not significantly increased. In univariate analysis, age, pre-existing cardiac disease, changes in pre- and post-treatment basal myocardial SUVmax and SUVmean (∆SUVmax and ∆SUVmean), and dosimetric parameters for MHD, mean LCX, mean LAD, and mean LV dose were associated with an increased hazard of MACEs. Multivariate analysis showed that basal ∆SUVmean retained significance after adjusting for age, pre-existing cardiac disease, and dosimetric parameters for whole heart and cardiac substructures. The AUCs and Brier scores demonstrated favorable predictive accuracies of the model's integrating variables with significant difference in multivariate analysis when predicting MACEs in the training and validation cohorts.

CONCLUSION

∆SUVmean was an independent indicator of MACE in locally advanced esophageal cancer patients receiving definitive radiotherapy. Changes in basal myocardial FDG uptake is a promising biomaker for predicting radiation-induced cardiotoxicity.

PD-L1 Inhibitors Combined with Thoracic Radiotherapy in First-Line Treatment of Extensive Stage Small Cell Lung Cancer: A Propensity Score-Matched, Real-World Study

PURPOSE/OBJECTIVE(S)

The CREST study showed that the addition of thoracic radiotherapy (TRT) could improve the survival of extensive stage small cell lung cancer (ES-SCLC), but whether TRT can bring survival benefit in the era of immunotherapy is controversial. This study aims to explore the efficacy and safety of adding TRT to the combination of PD-L1 inhibitors and chemotherapy.

MATERIALS/METHODS

Thepatients who received PD-L1 inhibitors combined with platinum-based chemotherapy as the first-line treatment of ES-SCLC from January 2019 to December 2021 were retrospectively collected. According to whether they received TRT, they were divided into two groups, and the follow-up analysis was performed. Propensity score matching (PSM) in with a 1:1 ratio was performed to balance the baseline characteristics of the two cohorts. The endpoints were progression-free survival (PFS) and OS.

RESULTS

A total of 211 patients with ES-SCLC were enrolled, of whom 70 (33.2%) patients received standard therapy plus TRT as first-line treatment, and 141 (66.8%) patients in the control group received PD-L1 inhibitors plus chemotherapy. After PSM, a total of 65 pairs of patients were enrolled in the analysis. There were no significant differences in baseline characteristics between the two groups of patients who received TRT and those who did not. In all patients, the median PFS (mPFS) in the TRT group and the non-TRT groupwere 9.5 months and 7.2 months, respectively, with HR = 0.60 (95% CI 0.41-0.87, p = 0.007). The median OS (mOS) in the TRT group was also significantly longer than that in the non-TRT group (24.1 months vs. 18.5 months, HR = 0.53, 95% CI 0.32-0.85, p = 0.009). Multivariable analysis showed that baseline liver metastasis and bone metastasis were independent prognostic factors for OS. In terms of safety, immunotherapy combined with thoracic radiotherapy increased the incidence of treatment-related pneumonia (p<0.001), most of which were grade 1-2.

CONCLUSION

This real-world study shows that adding TRT to durvalumab or atezolizumab plus chemotherapy significantly improves survival in ES-SCLC. It leads to more treatment-related pneumonia, but most of them can be relieved after symptomatic treatment. This treatment model deserves to be explored in prospective clinical trials.

Enhanced Radiosensitivity of Esophagus Cancer through Loss of ADAR1 and Cell Apoptosis via NF-kB Signaling Pathway

PURPOSE/OBJECTIVE(S)

RNA editing is a common posttranslational mechanism for generating genomic diversity by modifying selected RNA sequences without altering the genome. A new understanding of cancer therapy can be enhanced by the discovery of ADAR1 in the control of signal transduction pathways. However, the study of the biological effects of ADAR1 in radioresistance of esophageal cancer is not very deep.

MATERIALS/METHODS

The TCGA data sets were used to explore the correlations between ADAR1 and prognosis in esophageal cancer. Two pairs of ADAR1 gene siRNA fragments (siADAR1-1 and siADAR1-2) were designed and transiently transfected into KYSE410 cells and KYSE410-RT cells. The expression of ADAR1 was detected by RT-PCR and WB. Colony formation assay was used to evaluate the radiosensitivity. Apoptosis was measured using a flow cytometric apoptosis assay. Furthermore, transcriptome sequencing was performed to elucidate the pathways regulated by ADAR1.

RESULTS

In this study, we found that ADAR1 is overexpressed in esophageal tumors and is associated with poor prognosis in bioinformatics analysis. Colony formation experiment showed that siRNA-mediated depletion of ADAR1 in KYSE410 cells could inhibit cell proliferation and reduce radiosensitivity significantly. Consistently results were showed in KYSE410-RT cells. Mechanism studies revealed loss of ADAR1 induced cell apoptosis and radiotherapy could enhance this process. Transcriptomic data indicated that ADAR1 could regulate apoptosis through the NF-kB pathway.

CONCLUSION

RNA editing was found to be involved in the regulation of radiosensitivity of esophageal cancer and loss of ADAR1 can cause cell apoptosis though NF-kB pathway. A better understanding of A-to-I RNA editing and its oncogenic mechanisms may facilitate the development of radiotherapy in esophageal cancer.

Energetic Electron Precipitation Driven by Electromagnetic Ion Cyclotron Waves from ELFIN's Low Altitude Perspective

We review comprehensive observations of electromagnetic ion cyclotron (EMIC) wave-driven energetic electron precipitation using data collected by the energetic electron detector on the Electron Losses and Fields InvestigatioN (ELFIN) mission, two polar-orbiting low-altitude spinning CubeSats, measuring 50-5000 keV electrons with good pitch-angle and energy resolution. EMIC wave-driven precipitation exhibits a distinct signature in energy-spectrograms of the precipitating-to-trapped flux ratio: peaks at >0.5 MeV which are abrupt (bursty) (lasting ∼17 s, or Δ L ∼ 0.56 ) with significant substructure (occasionally down to sub-second timescale). We attribute the bursty nature of the precipitation to the spatial extent and structuredness of the wave field at the equator. Multiple ELFIN passes over the same MLT sector allow us to study the spatial and temporal evolution of the EMIC wave - electron interaction region. Case studies employing conjugate ground-based or equatorial observations of the EMIC waves reveal that the energy of moderate and strong precipitation at ELFIN approximately agrees with theoretical expectations for cyclotron resonant interactions in a cold plasma. Using multiple years of ELFIN data uniformly distributed in local time, we assemble a statistical database of ∼50 events of strong EMIC wave-driven precipitation. Most reside at L ∼ 5 - 7 at dusk, while a smaller subset exists at L ∼ 8 - 12 at post-midnight. The energies of the peak-precipitation ratio and of the half-peak precipitation ratio (our proxy for the minimum resonance energy) exhibit an L -shell dependence in good agreement with theoretical estimates based on prior statistical observations of EMIC wave power spectra. The precipitation ratio's spectral shape for the most intense events has an exponential falloff away from the peak (i.e., on either side of ∼ 1.45 MeV). It too agrees well with quasi-linear diffusion theory based on prior statistics of wave spectra. It should be noted though that this diffusive treatment likely includes effects from nonlinear resonant interactions (especially at high energies) and nonresonant effects from sharp wave packet edges (at low energies). Sub-MeV electron precipitation observed concurrently with strong EMIC wave-driven >1 MeV precipitation has a spectral shape that is consistent with efficient pitch-angle scattering down to ∼ 200-300 keV by much less intense higher frequency EMIC waves at dusk (where such waves are most frequent). At ∼100 keV, whistler-mode chorus may be implicated in concurrent precipitation. These results confirm the critical role of EMIC waves in driving relativistic electron losses. Nonlinear effects may abound and require further investigation.

Two Sweet Sorghum (Sorghum bicolor L.) WRKY Transcription Factors Promote Aluminum Tolerance via the Reduction in Callose Deposition

Aluminum (Al) toxicity is a primary limiting factor for crop production in acidic soils. The WRKY transcription factors play important roles in regulating plant growth and stress resistance. In this study, we identified and characterized two WRKY transcription factors, SbWRKY22 and SbWRKY65, in sweet sorghum (Sorghum bicolor L.). Al induced the transcription of SbWRKY22 and SbWRKY65 in the root apices of sweet sorghum. These two WRKY proteins were localized in the nucleus and exhibited transcriptional activity. SbWRKY22 showed the significant transcriptional regulation of SbMATE, SbGlu1, SbSTAR1, SbSTAR2a, and SbSTAR2b, which are major known Al tolerance genes in sorghum. Interestingly, SbWRKY65 had almost no effect on the aforementioned genes, but it significantly regulated the transcription of SbWRKY22. Therefore, it is speculated that SbWRKY65 might indirectly regulate Al-tolerance genes mediated by SbWRKY22. The heterologous expression of SbWRKY22 and SbWRKY65 greatly improved the Al tolerance of transgenic plants. The enhanced Al tolerance phenotype of transgenic plants is associated with reduced callose deposition in their roots. These findings suggest the existence of SbWRKY22- and SbWRKY65-mediated Al tolerance regulation pathways in sweet sorghum. This study extends our understanding of the complex regulatory mechanisms of WRKY transcription factors in response to Al toxicity.

[Advances in clinical characteristics of talaromycosis combined with other opportunistic infections]

Talaromycosis (TSM) is an opportunistic deep mycosis prevalent in southeast Asia and southern China, affecting HIV-positive, anti-interferon-gamma autoantibody-positive and other immunodeficiency hosts. These hosts are often co-infected with mycobacterium tuberculosis, non-tuberculosis mycobacteria, bacteria, fungi, viruses and other opportunistic infections. The clinical characteristics and the pathogenic spectrum of TSM with opportunistic infections vary with different immune states. The rates of misdiagnosis, missed diagnosis and mortality are high. This review summarized the clinical characteristics of TSM with opportunistic infections in order to improve the level of clinical diagnosis and treatment.

[Persistence follow-up of immune memory to hepatitis B vaccine among infants with non- and low-response to primary vaccination after revaccination with three doses]

This study followed up the immune memory after 3-dose revaccination among infants with non-and low-response following primary hepatitis B (HepB) vaccination. About 120 children without self-booster doses were finally included who had anti-HBs<10 mIU/ml (anti-HBs negative) at the time of follow-up, of whom 86 children completed blood sampling and anti-HBs testing. Before the challenge dose, all 86 children were negative for anti-HBs, and the GMC of anti-HBs was<10 mIU/ml. The seropositive conversion rate of anti-HBs was 100% and the GMC of anti-HBs was 886.11 (95%CI: 678.15-1 157.84) mIU/ml after the challenge dose. Compared with those with GMC<7 mIU/ml before the challenge dose, infants with GMC>7 mIU/ml had a higher anti-HBs level after the challenge dose. The β value (95%CI) was 0.82 (0.18-1.46) (P=0.012). Compared with those with GMC<1 000 mIU/ml at primary vaccination, infants with GMC≥1 000 mIU/ml had a higher anti-HBs level after the challenge dose. The β value (95%CI) was 0.78 (0.18-1.38)(P=0.012). The results showed a stronger immune memory was found at 9 years after revaccination among infants with non-and low-response to HepB.

Mechanism of action of non-coding RNAs and traditional Chinese medicine in myocardial fibrosis: Focus on the TGF-β/Smad signaling pathway

Cardiac fibrosis is a serious public health problem worldwide that is closely linked to progression of many cardiovascular diseases (CVDs) and adversely affects both the disease process and clinical prognosis. Numerous studies have shown that the TGF-β/Smad signaling pathway plays a key role in the progression of cardiac fibrosis. Therefore, targeted inhibition of the TGF-β/Smad signaling pathway may be a therapeutic measure for cardiac fibrosis. Currently, as the investigation on non-coding RNAs (ncRNAs) move forward, a variety of ncRNAs targeting TGF-β and its downstream Smad proteins have attracted high attention. Besides, Traditional Chinese Medicine (TCM) has been widely used in treating the cardiac fibrosis. As more and more molecular mechanisms of natural products, herbal formulas, and proprietary Chinese medicines are revealed, TCM has been proven to act on cardiac fibrosis by modulating multiple targets and signaling pathways, especially the TGF-β/Smad. Therefore, this work summarizes the roles of TGF-β/Smad classical and non-classical signaling pathways in the cardiac fibrosis, and discusses the recent research advances in ncRNAs targeting the TGF-β/Smad signaling pathway and TCM against cardiac fibrosis. It is hoped, in this way, to give new insights into the prevention and treatment of cardiac fibrosis.

RNA-binding protein MAC5A interacts with the 26S proteasome to regulate DNA damage response in Arabidopsis

DNA damage response (DDR) in eukaryotes is essential for the maintenance of genome integrity in challenging environments. The regulatory mechanisms of DDR have been well-established in yeast and humans. However, increasing evidence supports the idea that plants seem to employ different signaling pathways that remain largely unknown. Here, we report the role of MODIFIER OF SNC1, 4-ASSOCIATED COMPLEX SUBUNIT 5A (MAC5A) in DDR in Arabidopsis (Arabidopsis thaliana). Lack of MAC5A in mac5a mutants causes hypersensitive phenotypes to methyl methanesulfonate (MMS), a DNA damage inducer. Consistent with this observation, MAC5A can regulate alternative splicing of DDR genes to maintain the proper response to genotoxic stress. Interestingly, MAC5A interacts with the 26S proteasome (26SP) and is required for its proteasome activity. MAC core subunits are also involved in MMS-induced DDR. Moreover, we find that MAC5A, the MAC core subunits, and 26SP may act collaboratively to mediate high-boron-induced growth repression through DDR. Collectively, our findings uncover the crucial role of MAC in MMS-induced DDR in orchestrating growth and stress adaptation in plants.

Characterization of GmMATE13 in its contribution of citrate efflux and aluminum resistance in soybeans

Citrate exudation mediated by a citrate transporter of the MATE protein family is critical for resisting aluminum (Al) toxicity in soybeans. However, the expression patterns of citrate transporter genes differ under Al stress. Thus, exploring the responsive pattern of GmMATEs in response to Al stress is of great importance to understand the Al resistance mechanism in soybeans. In the present study, the phylogenetic analysis, transcriptionally expressed pattern, and function of GmMATE13 were investigated. The results show that soybean GmMATE13 is highly homologous to known citrate transporter proteins from other plants. Under Al exposure, the transcript abundance of GmMATE13 was increased during a 24 h Al treatment period. The expression of GmMATE13 is specifically induced by Al exposure, but not by the status of Fe, Cu, Cd, or La. Moreover, it was also highly increased when soybean seedlings were grown on acidic soil with a high Al content. Subcellular localization showed that GmMATE13 was localized on the plasma membrane when it was transiently expressed in Arabidopsis protoplasts. Investigation of tissue localization of GmMATE13 expression by investigating GUS activity staining under control of the GmMATE13 promoter showed that it was mainly expressed in the central cylinder in the root tips of the soybean under Al-free conditions, yet extended to cortical and epidermis cells under Al stress. Finally, overexpressing GmMATE13 in soybean hairy roots enhanced Al resistance by increasing citrate efflux. Collectively, we conclude that GmMATE13 is a promising candidate to improve the resistance of soybean to Al toxicity in acidic soil.

To what extent do social support and mastery mediate the association between childhood maltreatment and depression? A sequential causal mediation analysis

AIMS

This study aimed to examine the independent roles of various childhood maltreatment (CM) subtypes in the development of depression; quantify the joint mediation effect of social support and mastery in the association between subtypes of CM and depression and examine the additional contribution of mastery beyond the effect that is operating through social support to this relationship.

METHODS

Data analysed were from the Zone d'Épidémiologie Psychiatrique du Sud-Ouest de Montréal, an ongoing longitudinal population-based study. In total, 1351 participants with complete information on the studied variables were included. The propensity score matching and inverse-probability weighted regression adjustment estimation methods were used to minimise the potential confounding in the relationship between CM and major depression. We then used inverse odds ratio-weighted estimation to estimate the direct effects of maltreatment and indirect effects of social support and mastery.

RESULTS

We found that exposures to all maltreatment subtypes increased the risk of subsequent depression. The joint mediating effect of social support and mastery explained 37.63-46.97% of the association between different maltreatment subtypes and depression. The contribution of these two mediators differed by maltreatment subtypes, with social support being the major contributor to the mediating effect.

CONCLUSIONS

The findings of the study not only provide scientific evidence on the importance of psychosocial attributes in the development of major depression but also suggest that prevention and invention strategies should focus on these psychosocial attributes to effectively break the vicious cycle of CM on major depression.

The Double-Edged Sword Effect of Paradoxical Leadership to Organizational Citizenship Behavior

Purpose

Drawing on social exchange theory and attribution theory, this study aims to explore the influencing mechanism of paradoxical leadership on organizational citizenship behavior.

Participants and Methods

According to the research purpose, this study selects enterprises in the manufacturing, financial and high-tech industries in Shandong Province as the research objects, and collects data on the leaders and employees of the human resources departments and marketing departments in the enterprises. Data were collected from 77 leaders and 473 employees in China by a two-wave questionnaire survey. Hierarchical regression analysis and structural equation model approach were employed to test hypotheses.

Results

This study found that perceived insider status and psychological entitlement play mediating roles about paradoxical leadership and organizational citizenship behavior; Collectivism moderates the relationship between paradoxical leadership and perceived insider status, and moderates the positive mediating role played by perceived insider status in the relationship of paradoxical leadership and organizational citizenship behavior; Leader-member exchange differentiation moderates the relationship about paradoxical leadership and psychological entitlement, and moderates negative mediating role played by psychological entitlement in the relationship of paradoxical leadership's and organizational citizenship behavior.

Conclusion

The findings of this study offer guidance for managers to better undermine the negative effects of paradoxical leadership, and improve organizational citizenship behavior.

Innovations

First, this study extends the literature on paradoxical leadership by verifying the double-edged sword effect of paradoxical leadership to organizational citizenship behavior. Second, this study enriches one's understanding of the "black box" underlying the link between paradoxical leadership and its consequences by demonstrating the mediating roles of perceived insider status and psychological entitlement. Third, by verifying the moderating roles of collectivism and leader-member exchange differentiation, this study provides insights into the boundary conditions of the impact of paradoxical leadership.

Kinetic Model and Numerical Simulation of Microbial Growth, Migration, and Oil Displacement in Reservoir Porous Media

Microbial enhanced oil recovery (MEOR) is a potential tertiary oil recovery method. However, past research has failed to describe microbial growth and metabolism reasonably, especially quantification of reaction equations and operating parameters is still not clear. The present study investigated the ability of bacteria extracted from Ansai Oilfield for MEOR. Through core flooding experiments, bacteria-treated experiments produced approximately 6.28-9.81% higher oil recovery than control experiments. Then, the microbial reaction kinetic model was established based on laboratory experimental data and mass conservation. Furthermore, the proposed model was validated by matching core flooding experiment results. Lastly, the effects of different injection parameters on bacteria growth, bacteria migration, metabolite migration, residual oil distribution, and oil recovery were studied by establishing a field-scale model. The results indicate that the injected bacteria concentration and nutrient concentration have a great influence on bacteria growth in a reservoir and the low nutrient concentration seriously restricts bacteria growth. Compared with the injected bacteria concentration, nutrient concentration has a decisive effect on bacteria and metabolite migration. The injected bacteria concentration has little effect on oil recovery, while nutrient concentration and slug volume have a significant effect on oil recovery.

Hybrid non-sequential modeling of an image mapping spectrometer

An image mapping spectrometer (IMS) is a kind of snapshot imaging spectrometer characterized by containing several array components including the image mapper, prism array, and reimaging lens array. We propose a hybrid non-sequential modeling method of IMS and present the complete optical model of the system built in Zemax. This method utilizes the spatial periodicity of the array components and requires only a small number of input parameters. Moreover, we design a collimating lens of a large relative aperture, sufficient working distance, and low aberration to meet the requirements of an IMS with good optical performance and compact volume. The designed lens is quantitatively evaluated in the entire IMS model, and the results demonstrate that the lens has excellent optical performance. The evaluation on the collimating lens also demonstrates the capability of the proposed modeling method in the design and optimization of systems such as the IMS that contain multiple array components. The designed collimating lens is manufactured and assembled in the experimental setup of the IMS. The proposed modeling method is verified by experimental results.

[Anti-HBs persistence after primary vaccination with three doses of 5 μg recombinant hepatitis B vaccine among normal and high-responder infants: 10-year of follow-up]

Objective: Assess the 10-year Immune persistence and the predictors after primary vaccination hepatitis B vaccine (HepB) among normal and high-responder infants. Methods: A total of 1 838 Infants of 7-12 months old located in Jinan, Weifang, Yantai and Weihai of Shandong Province who were induced normal or high antibody response (anti-HBs titer ≥ 100 mIU/ml) after primary vaccination (three dose with 0-1-6 procedure) with 5 μg recombinant HepB among newborns were included in the study, in 2009. 3 ml of venous blood samples were collected at baseline survey (T₀) and antibodies against hepatitis B surface antigen (anti-HBs), antibody against hepatitis B core antigen (anti-HBc) and hepatitis B surface antigen (HBsAg) were detected using chemiluminescence microparticle immunoassay (CMIA) method. A self-designed questionnaire was used to collect information including the infant's age, sex, birth weight, premature birth, birth number, delivery location and mother's HBV infection status. In 2014 (followed up for 5 years) and in 2019 (followed up for 10 years) (T₁), 2 ml of venous blood samples were collected. Anti HBS and anti HBC were detected by CMIA method. Those with anti HBS<10 mIU/ml were detected by CMIA method. Multivariate unconditional logistic and linear regression models were used to analyze the influencing factors of anti-HBs positive rate and geometric mean concentration (GMC) at T₁. Results: After 10 years follow-up, 73.94% of the subjects (1 359/1 835) finished the follow-up. 51.15% of the subjects, a total of 625 were boys. The positive rate of anti-HBs was 100% at T₀ and decreased to 53.44% (95%CI: 50.59%-56.26%) at T₁. The average annual decline rate of anti-HBs positive rate from T₀ to T₁ was 6.07%. The GMC of anti-HBs decreased from 607.89 (95%CI: 579.01-642.62) mIU/ml to 16.44 (95%CI: 15.06-18.00) mIU/ml. The average annual decline rate of anti-HBs GMC in 10-year follow-up was 30.30%. Multivariate logistic analysis showed that the positive rate of anti-HBs at T₁ was lower in those who did not vaccinate the first dose in time (OR=0.25, 95%CI:0.07-0.71). Compared with those with GMC<1 000 mIU/ml at T₀, those with GMC ≥ 1 000 mIU/ml had a higher positive rate of anti-HBs at T₁ (OR=2.29, 95%CI:1.76-2.97). Multivariate regression analysis showed that the GMC of anti-HBs at T₁ was lower in those who did not vaccinate the first dose in time (β=-0.50, 95%CI:-1.24-0.24). Compared with those with GMC<1 000 mIU/ml at T₀, those with GMC ≥ 1 000 mIU/ml had a higher GMC of anti-HBs at T₁ (β=0.81, 95%CI: 0.62-1.05). Conclusion: Anti-HBs GMC decreased in 10 years after primary vaccination of 5 μg recombinant hepatitis B vaccine among normal and high-responders. The anti-HBs persistence was mainly associated with whether the first dose was vaccinated in time and the level of anti-HBs at the end of primary vaccination.

The efficacy and safety of different doses of calcitriol combined with neutral phosphate in X-linked hypophosphatemia: a prospective study

The present study was the first prospective cohort evaluated the efficacy and safety of different doses of calcitriol in XLH children. The results suggested that a dose of 40 ng/kg/day calcitriol, compared with 20 ng/kg/day, was more effective in relieving the rickets, with similar safety outcomes. Further investigations were expected to set more dose groups.

INTRODUCTION

Dose recommended for calcitriol in X-linked hypophosphatemia (XLH) varies in different studies. Therefore, we aimed to compare the efficacy as well as the safety of 20 ng/kg/d and 40 ng/kg/d calcitriol in Chinese XLH pediatrics population.

METHODS

A 2-year, randomized, open-label, prospective study recruited 68 XLH children, which were randomized to receive either 40 ng/kg/day or 20 ng/kg/day calcitriol. Efficacy endpoints were the total Thacher ricket severity score (RSS) change from baseline to month 12 and 24, the difference in serum TALP level, fasting serum phosphate level, body height Z-score, and frequency of dental abscess. Safety assessments were done using renal ultrasound nephrocalcinosis grades (0-4), fasting serum and 24 h urine calcium level, and the occurrence of hyperparathyroidism.

RESULTS

The decrease in the total RSS from baseline was more significant in the high-dose group at 12 (difference 0.87, p = 0.049) and 24 month (difference 1.23, p = 0.011). The serum TALP level was significantly lower in the high-dose group at 6 months. Pi level, height Z-score change, frequency of dental abscess and ratio of de novo nephrocalcinosis were comparable. A lower incidence of secondary hyperparathyroidism was seen in the high-dose group (p < 0.0001).

CONCLUSION

For the first time in this prospective cohort, 40 ng/kg/d calcitriol was shown to be the more effective therapy in XLH children than the 20 ng/kg/d. Moreover, 40 ng/kg/d calcitriol was not associated with increasing adverse events.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT 03,820,518.

POS1016 RELATIONSHIPS BETWEEN DISEASE DURATION AND RADIOGRAPHIC PROGRESSION AMONG PATIENTS WITH PSORIATIC ARTHRITIS TREATED WITH SECUKINUMAB IN FUTURE 5

Background

For patients with psoriatic arthritis (PsA), delays in diagnosis and treatment can lead to permanent radiographic damage, even early in the course of disease.1 In the phase 3 FUTURE 5 study (NCT02404350), treatment with secukinumab (SEC) was shown to inhibit progression of structural damage through Week 104 in patients with PsA.2 However, the effect of disease duration on inhibition of radiographic progression by SEC has not been characterized.

Objectives

This post hoc analysis explored relationships between time since diagnosis (TSD) of ≤1 year vs >1 year and radiographic progression among patients with PsA receiving SEC over 2 years in FUTURE 5.

Methods

Patient data from FUTURE 5 were stratified by TSD ≤1 year vs >1 year and analyzed by treatment arm. Through Week 24, patients received SEC 300 or 150 mg with subcutaneous loading dose (LD), SEC 150 mg without LD, or placebo (PBO) (period 1). After Week 24, patients receiving PBO were switched to SEC 300 or 150 mg (period 2), and a protocol amendment allowed those with suboptimal clinical response to SEC 150 mg to escalate to SEC 300 mg after Week 52 per investigator judgment.2 The proportion of patients with no radiographic progression, defined as change from baseline in van der Heijde total modified Sharp score ≤0.0, was analyzed at Weeks 24, 52, and 104. Mean total Sharp score was evaluated at baseline, and mean change from baseline was determined at Weeks 24, 52, and 104.

Results

Of 996 patients with PsA included here, 217 (21.8%) had a TSD ≤1 year and 779 (78.2%) had a TSD >1 year. At baseline, patients with TSD >1 year had greater radiographic damage than patients with TSD ≤1 year as determined by mean total Sharp score (Table 1). As early as Week 24, patients receiving SEC had less radiographic progression than those receiving PBO, regardless of TSD. From Week 24 to Week 104, radiographic progression remained low among all patients receiving SEC, with a trend of least progression among patients randomized to SEC 300 mg at baseline. Regardless of treatment, patients with TSD >1 year had numerically greater radiographic progression than those patients with TSD ≤1 year. Overall, the proportion of patients receiving SEC who did not have any radiographic progression was higher than that of placebo at Week 24 irrespective of TSD, with a trend towards a higher number of non-progressors among those treated with SEC 300 mg (Figure). Patients randomized to SEC 300 mg were the least likely to experience radiographic progression through 52 weeks.

Table 1.

Baseline Total Sharp Score and Change From Baseline at Weeks 24, 52, and 104 by TSD

Total Sharp scoreTSD ≤1 yearTSD >1 yearPeriod 1SEC 300 mg n = 54SEC 150 mg n = 46SEC 150 mg NL n = 43PBO n = 74SEC 300 mg n = 168SEC 150 mg n = 174SEC 150 mg NL n = 179PBO n = 258Baseline, mean (SD)8.02 (20.77)8.82 (12.06)12.74 (33.67)8.84 (20.42)14.37 (24.17)14.67 (28.01)15.56 (37.52)17.34 (41.21)Week 24 change from baseline, mean (SD)0.05 (0.72)−0.08 (1.40)−0.61 (5.25)0.76 (2.05)0.09 (1.37)0.23 (1.24)0.03 (2.05)0.42 (1.56)Period 2SEC 300 mg* n = 54SEC 150 mg†n = 46SEC 150 mg NL†n = 43PBO ‒ 300 mg n = 40PBO ‒ 150 mg†n = 30SEC 300 mg* n = 168SEC 150 mg†n = 174SEC 150 mg NL†n = 179PBO ‒ 300 mg n = 113PBO ‒ 150 mg†n = 123Week 52 change from baseline, mean (SD)0.05 (0.48)−0.03 (1.22)0.35 (2.25)0.22 (0.70)0.18 (0.75)−0.07 (1.16)0.26 (1.96)0.26 (1.05)0.16 (0.94)0.40 (2.00)Week 104 change from baseline, mean (SD)0.06 (0.63)0.11 (0.99)0.20 (2.71)0.11 (0.68)−0.07 (0.50)0.11 (2.00)0.62 (2.94)0.46 (2.08)0.12 (0.90)0.81 (2.66)

NL, no loading dose; PBO, placebo; SEC, secukinumab; TSD, time since diagnosis.

* One outlier in the 300-mg dose group was excluded.

† Includes patients who received dose escalation to SEC 300 mg after Week 52.

Conclusion

SEC resulted in low rates of radiographic progression through 2 years of treatment among patients in FUTURE 5, regardless of time since PsA diagnosis.

References

[1]Haroon M, et al. Ann Rheum Dis. 2015;74:1045-50.

[2]Mease P, et al. RMD Open. 2021;7:e001600.

Acknowledgements

This study was funded by Novartis Pharmaceuticals Corporation. Medical writing support was provided by Richard Karpowicz, PhD, CMPP, of Health Interactions, Inc, and was funded by Novartis Pharmaceuticals Corporation. This abstract was developed in accordance with Good Publication Practice (GPP3) guidelines. Authors had full control of the content and made the final decision on all aspects of this publication.

Disclosure of Interests

Christopher T. Ritchlin Consultant of: AbbVie, Amgen, Eli Lilly, Janssen, Pfizer, Novartis, Gilead, and UCB, Ana-Maria Orbai Consultant of: Bristol Myers Squibb, Janssen, Lilly, Novartis, Pfizer, and UCB, Grant/research support from: to Johns Hopkins University from AbbVie, Amgen, Celgene, Horizon, Janssen, Lilly, and Novartis, Bhumik Parikh Employee of: Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA, Corine Gaillez Employee of: Novartis Pharma AG, Basel, Switzerland, Xiangyi Meng Employee of: Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA, Philip J Mease Speakers bureau: AbbVie, Amgen, Janssen, Eli Lilly, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Galapagos, Gilead, GlaxoSmithKline, Janssen, Eli Lilly, Novartis, Pfizer, Sun Pharma, and UCB, Grant/research support from: AbbVie, Amgen, Bristol Myers Squibb, Celgene, Gilead, Janssen, Eli Lilly, Novartis, Pfizer, Sun Pharma, and UCB

OP0076 L-ARGININE REPROGRAMS OSTEOCLAST PURINE METABOLISM AMELIORATING BONE LOSS IN RHEUMATOID ARTHRITIS

Background

Bone erosion is a clinical feature of rheumatoid arthritis related to disease severity and poor functional prognosis. Excessive osteoclast differentiation and insufficient osteoblast function are the main reasons for the erosive process in RA. Our previous investigation indicated that L-arginine supplementation not only diminished arthritic inflammation in the serum-induced arthritis (K/BxN) model but also decreased inflammatory joints osteoclast numbers (1).

Objectives

In the present study, we aim to investigate the metabolic action of L-arginine supplementation in RA, especially on periarticular bone erosion and systemic bone loss. We plan to depict the metabolic features of TNFα induced inflammatory osteoclasts after in vitro L-arginine supplementation.

Methods

Three murine arthritis models (serum-induced arthritis (K/BxN) model, collagen-induced arthritis model, and hTNFtg mice model) were analysed in this study. L-arginine was supplemented within the drinking water after the onset of arthritis. Bone parameters for axial skeleton (spine) and peripheral skeleton (tibia) from the respective group were quantified by μCT. HE and TRAP staining were performed to address further the erosion area and osteoclast numbers in periarticular sites. In vitro osteoclast differentiation was conducted with or without L-arginine treatment, in the presence or not of TNFα activation. Seahorse and SCENITH analyses were adopted to delineate the metabolic features. JC-1 staining and transmission electron microscopy (TEM) were used to depict the mitochondria metabolism. RNA-seq and mass spectrometry (MS) were performed to investigate the underlying molecular mechanism.

Results

Inflammation was diminished in all three arthritis models after L-arginine supplementation with a significant reduction in arthritic score. Moreover, an amelioration of periarticular bone erosion, systemic bone loss, and decreased osteoclast numbers in periarticular sites were observed in arthritic mice after L-arginine treatment. L-arginine also inhibited osteoclastogenesis in vitro, particularly under TNFα activation. Seahorse and SCENITH analyses indicated TNFα promoted glycolysis while blocking mitochondria-driven oxidative phosphorylations (OXPHOS) in pre-osteoclasts. Meanwhile, JC-1 staining and TEM images also showed that TNFα decreased mitochondria membrane potential and prompted damage of mitochondria. Surprisingly, L-arginine rescued the TNFα inhibition of OXPHOS while promoting ATP production.

RNA-seq and MS data confirmed the boost of OXPHOS after L-arginine treatment under TNFα activation. To interfere with OXPHOS, L-arginine inhibited cJun thus altered arginase-1 and arginase-2 expression. Moreover, the increased ATP in L-arginine treated cells facilitated purine metabolism, especially the production of inosine and hypoxanthine, contributing to the inhibition of osteoclastogenesis. Increasing Adenosine deaminase (ADA) is essential for the production of inosine and hypoxanthine due to the decreased inhibitory regulation of the transcription factor c-Jun.

Conclusion

These data strongly demonstrated that L-arginine ameliorates bone erosion in RA through metabolic reprogramming and perturbation of purine metabolism in osteoclasts. L-arginine might therefore benefit RA therapy by reducing joint inflammation and also ameliorating bone destruction.

References

[1]Hannemann, Nicole, et al. “Transcription factor Fra-1 targets arginase-1 to enhance macrophage-mediated inflammation in arthritis.” The Journal of clinical investigation 129.7 (2019): 2669-2684.

Disclosure of Interests

Shan Cao: None declared, Rui Song: None declared, Xianyi Meng: None declared, Katerina Kachler: None declared, Maximilian Fuchs: None declared, Xinyu Meng: None declared, Yixuan Li: None declared, Verena Taudte: None declared, Meik Kunz: None declared, Ursula Schloetzer-Schrehardt: None declared, Ulrike Schleicher: None declared, Xiaoxiang Chen Speakers bureau: AbbVie, Roche and Novartis, Georg Schett Speakers bureau: AbbVie, BMS, Celgene, Janssen, Eli Lilly, Novartis, Roche and UCB, Aline Bozec: None declared.

POS0409 INTESTINAL HIF1α EXPRESSION PROTECTS AGAINST EPITHELIAL CELL DEATH IN ARTHRITIS

Background

While a so-called gut-joint axis is supported by many clinical observations, the current knowledge on such axis is mostly confined to descriptive and correlative data, e.g. showing the microbiota changes are associated with arthritis. In contrast, mechanistic data on how molecular changes in the intestinal epithelium influence the development of arthritis are scarce.

Objectives

To investigate, whether the mucosal barrier in the intestine dependent of the epithelial cell survival maintenance, influences the development of arthritis.

Methods

Intestinal hypoxia inducible factor (HIF)-1α expression was assessed before, at onset and during experimental arthritis and human rheumatoid arthritis (RA). Intestinal epithelial cell-specific HIF1α conditional knock-out mice were generated (HIF1αΔIEC) and subjected to collagen-induced arthritis (CIA). Clinical and histological courses of arthritis were recorded, and T and B cell subsets were analyzed in the gut and secondary lymphatic organs, and intestinal epithelial cells were subjected to molecular mRNA sequencing in HIF1αΔIEC and littermate control mice. Furthermore, pharmacologic HIF1α stabilization by PHD inhibitor was used for the treatment of arthritis.

Results

Intestinal HIF1α expression peaked at onset and remained high in experimental arthritis and RA. Conditionally deletion of HIF1α in gut epithelial cells strongly exacerbate arthritis and was associated with increased gut epithelial cell death, intestinal and lymphatic Th1 and Th17 activation. Mechanistically, HIF1α inhibits the transcription of necroptotic and apoptotic markers, which leads to a defect in the intestinal barrier integrity. Furthermore, treatment with HIF1α stabilization reinforced the gut epithelial cell survival and inhibited arthritis.

Conclusion

These findings show that the HIF1α regulating epithelial cells survival is critical for the breakdown of the intestinal barrier function in arthritis highlighting the functional link between intestinal homeostasis and arthritis.

Disclosure of Interests

None declared.

POS1022 RELATIONSHIPS BETWEEN INHIBITION OF RADIOGRAPHIC PROGRESSION AND ACHIEVEMENT OF LOW DISEASE ACTIVITY OR REMISSION AND THEIR CORE COMPONENTS IN PATIENTS WITH PSORIATIC ARTHRITIS TREATED WITH SECUKINUMAB IN FUTURE 5 DURING THE FIRST 24 WEEKS

Background

Patients with active psoriatic arthritis (PsA) experience inflammation that may result in structural damage and disability. In the phase 3 FUTURE 5 study, treatment with secukinumab (SEC) inhibited radiographic progression and led to sustained remission and low disease activity (LDA) through Week 104.1,2

Objectives

This post hoc analysis of FUTURE 5 explored relationships between radiographic progression status and achievement of LDA or remission in patients treated with SEC.

Methods

Patients were randomized 2:2:2:3 to receive SEC 300 mg with loading dose (LD), 150 mg LD, SEC 150 mg without LD, or placebo (PBO) at Baseline, Weeks 1, 2, 3, 4, and every 4 weeks thereafter until Week 24. In this post hoc analysis, patients were grouped by radiographic progression status at Week 24 (non-radiographic progressors: change from baseline in modified total Sharp score [mTSS] ≤0.0; radiographic progressors: change from baseline in mTSS >0.0). Efficacy (achievement of Minimal Disease Activity [MDA] or Very Low Disease Activity [VLDA] and their individual components, and Disease Activity Index for Psoriatic Arthritis [DAPSA] LDA or remission) was assessed at Week 24.

Results

Of 933 patients with available data, 675 (72.3%) were classified as non-radiographic progressors and 258 (27.7%) were radiographic progressors at Week 24. Non-progressors at Week 24 were more likely than progressors to achieve DAPSA LDA and remission at Week 24 across all treatment arms (Figure 1A). In addition, non-progressors were more likely to achieve MDA and VLDA at Week 24 than progressors across all treatment arms (Figure 1B). Similar trends were observed for all of the individual MDA/VLDA criteria at Week 24 among patients treated with SEC 300 mg or SEC 150 mg LD (Table 1). Notably, non-progressors were more likely to achieve improvements in physical function, pain, and patient global assessment of disease activity than progressors across all treatment arms.

Table 1.

Proportion of Patients Achieving MDA/VLDA Components at Week 24 Grouped by Radiographic Progression Status at Week 24

Week 24 non-progressorsWeek 24 progressorsOutcome, n/N (%)SEC 300 mg n = 166SEC 150 mg n = 150SEC 150 mg NL n = 159PBO n = 200SEC 300 mg n = 51SEC 150 mg n = 63SEC 150 mg NL n = 51PBO n = 93TJC78 ≤152/161 (32.3)46/146 (31.5)37/150 (24.7)38/196 (19.4)15/50 (30.0)13/62 (21.0)13/49 (26.5)11/90 (12.2)SJC76 ≤1105/160 (65.6)85/146 (58.2)83/150 (55.3)88/196 (44.9)32/50 (64.0)28/62 (45.2)20/49 (40.8)30/90 (33.3)PASI ≤1 or BSA ≤3%99/128 (77.3)90/128 (70.3)69/109 (63.3)64/153 (41.8)29/38 (76.3)27/47 (57.4)28/40 (70.0)26/70 (37.1)Patient pain VAS ≤1557/144 (39.6)50/133 (37.6)50/141 (35.5)33/179 (18.4)14/42 (33.3)15/60 (25.0)13/43 (30.2)7/82 (8.5)PtGA VAS ≤2063/145 (43.4)47/125 (37.6)50/135 (37.0)39/173 (22.5)13/41 (31.7)14/61 (23.0)13/41 (31.7)7/81 (8.6)HAQ-DI ≤0.572/135 (53.3)55/118 (46.6)54/122 (44.3)47/158 (29.7)13/39 (33.3)18/58 (31.0)17/39 (43.6)19/77 (24.7)Tender entheseal points ≤170/87 (80.5)44/63 (69.8)42/76 (55.3)45/88 (51.1)13/18 (72.2)17/31 (54.8)11/19 (57.9)23/38 (60.5)

BSA, body surface area; HAQ-DI, Health Assessment Questionnaire Disability Index; MDA, Minimal Disease Activity; NL, no loading dose; PASI, Psoriasis Area and Severity Index; PBO, placebo; PtGA, patient global assessment of disease activity; SEC, secukinumab; SJC, swollen joint count; TJC, tender joint count; VAS, visual analog scale; VLDA, Very Low Disease Activity.

Conclusion

Patients who did not have radiographic progression over 6 months of SEC treatment were more likely to achieve LDA or remission and improvement in physical function at Week 24. Additional analyses will explore relationships between radiographic progression and additional clinical and patient-reported outcomes over longer time periods.

References

[1]Mease P, et al. RMD Open. 2021;7:e001600.

[2]Coates LC, et al. Ann Rheum Dis. 2021;80:803-4.

Acknowledgements

This study was funded by Novartis Pharmaceuticals Corporation. Medical writing support was provided by Eric Deutsch, PhD, CMPP, of Health Interactions, Inc, and was funded by Novartis Pharmaceuticals Corporation. This abstract was developed in accordance with Good Publication Practice (GPP3) guidelines. Authors had full control of the content and made the final decision on all aspects of this publication.

Disclosure of Interests

Philip J Mease Speakers bureau: AbbVie, Amgen, Janssen, Eli Lilly, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Galapagos, Gilead, GlaxoSmithKline, Janssen, Eli Lilly, Novartis, Pfizer, Sun Pharma, and UCB, Grant/research support from: AbbVie, Amgen, Bristol Myers Squibb, Celgene, Gilead, Janssen, Eli Lilly, Novartis, Pfizer, Sun Pharma, and UCB, Ana-Maria Orbai Consultant of: Bristol Myers Squibb, Janssen, Lilly, Novartis, Pfizer, and UCB, Grant/research support from: To Johns Hopkins University from AbbVie, Amgen, Celgene, Horizon, Janssen, Lilly, and Novartis, Bhumik Parikh Employee of: Novartis Pharmaceuticals Corporation, Corine Gaillez Employee of: Novartis Pharma AG, Xiangyi Meng Employee of: Novartis Pharmaceuticals Corporation, Christopher T. Ritchlin Consultant of: AbbVie, Amgen, Eli Lilly, Janssen, Pfizer, Novartis, Gilead, and UCB

GWAS on multiple traits identifies mitochondrial ACONITASE3 as important for acclimation to submergence stress

Flooding causes severe crop losses in many parts of the world. Genetic variation in flooding tolerance exists in many species; however, there are few examples for the identification of tolerance genes and their underlying function. We conducted a genome-wide association study (GWAS) in 387 Arabidopsis (Arabidopsis thaliana) accessions. Plants were subjected to prolonged submergence followed by desubmergence, and seven traits (score, water content, Fv/Fm, and concentrations of nitrate, chlorophyll, protein, and starch) were quantified to characterize their acclimation responses. These traits showed substantial variation across the range of accessions. A total of 35 highly significant single-nucleotide polymorphisms (SNPs) were identified across the 20 GWA datasets, pointing to 22 candidate genes, with functions in TCA cycle, DNA modification, and cell division. Detailed functional characterization of one candidate gene, ACONITASE3 (ACO3), was performed. Chromatin immunoprecipitation followed by sequencing showed that a single nucleotide polymorphism in the ACO3 promoter co-located with the binding site of the master regulator of retrograde signaling ANAC017, while subcellular localization of an ACO3-YFP fusion protein confirmed a mitochondrial localization during submergence. Analysis of mutant and overexpression lines determined changes in trait parameters that correlated with altered submergence tolerance and were consistent with the GWAS results. Subsequent RNA-seq experiments suggested that impairing ACO3 function increases the sensitivity to submergence by altering ethylene signaling, whereas ACO3 overexpression leads to tolerance by metabolic priming. These results indicate that ACO3 impacts submergence tolerance through integration of carbon and nitrogen metabolism via the mitochondrial TCA cycle and impacts stress signaling during acclimation to stress.

Disturbance Observer-Based Feedback Linearization Control for a Quadruple-Tank Liquid Level System

A novel input/output feedback linearization control method by utilizing nonlinear disturbance observer (NDOB) is proposed for a quadruple-tank liquid level (QTLL) system in this paper. Firstly, the mathematical model of QTLL system is established by using Bernoulli's law and mass conservation. Secondly, in view of the nonlinear and coupling characteristics of the QTLL system, a input/output feedback linearization controller is designed. Then, a NDOB is proposed to estimate disturbances and applied to compensation control. Finally, simulation and experimental results show that the proposed strategy has better control performances than PID control and the disturbance observer-based sliding mode control (DOBSMC).

Ectopic expression of IMA small peptide genes confers tolerance to cadmium stress in Arabidopsis through activating the iron deficiency response

Increasing cadmium (Cd) pollution severely affects plant growth and development, posing risks to human health via food chains. The Cd toxicity could be mitigated by improving Fe nutrient in plants. IMA1 and IMA3, two novel small peptides functionally epistatic to the key transcription factor bHLH39 but independent of bHLH104, were recently identified as the newest additions to the Fe regulatory cascade, but their roles in Cd uptake and toxicity remain not addressed. Here, the functions of two IMAs and two transcription factors related to Cd tolerance were verified. Overexpression of either bHLH39 or bHLH104 in Arabidopsis showed weak roles in Cd tolerance, but overexpression of IMAs, which activates the Fe-deficient response, significantly enhanced Cd tolerance, showing greater root elongation, biomass and chlorophyll contents. The Cd contents did not show significant difference among the overexpression lines. Further investigations revealed that the tolerance of transgenic plants to Cd mainly depended on higher Fe accumulation, which decreased the MDA contents and enhanced root elongation under Cd exposure, finally contributing to attenuating Cd toxicity. Taken together, the results suggest that increasing Fe accumulation is promising for improving plant tolerance to Cd toxicity and that IMAs are potential candidates for solving Cd toxicity problem.

Research on the Influence of Paradoxical Leadership on Compulsory Organizational Citizenship Behavior

PURPOSE

According to attribution theory, the purpose of this paper is to examine the relationship between paradoxical leadership and employees' compulsory organizational citizenship behavior, research the mediating and moderating effects of work pressure perception and leadership member exchange differentiation.

PARTICIPANTS AND METHODS

The data collection work was carried out with 329 employees as the research object, and empirical tests were carried out using confirmatory factor analysis and hierarchical regression analysis methods.

RESULTS

The results of the empirical test show that: paradoxical leadership has a significant positive effect on employees' compulsory organizational citizenship behavior; work pressure perception plays a mediating role between paradoxical leadership and employee's compulsory organizational citizenship behavior; leadership member exchange differentiation plays a moderating role between paradoxical leadership and work pressure perception. Paradoxical leadership will lead employees to adopt compulsory organizational citizenship behavior. Moreover, organizations should reduce employees' perception of work pressure and leadership member exchange differentiation.

CONCLUSION

The results of the study provide positive suggestions for reducing the compulsory organizational citizenship behavior of employees by focusing on the behavior of paradoxical leadership, thereby promoting the improvement of corporate performance.

INNOVATIONS

1) The research on the influence of paradoxical leadership on compulsory organizational citizenship behavior reveals the "dark side" of the influence of paradoxical leadership on employee behavior. 2) By introducing work pressure perception, this paper reveals the mechanism of action between paradoxical leadership and compulsory organizational citizenship behavior, which provides a new research perspective for understanding the formation mechanism of employees adopting compulsory organizational citizenship behavior. 3) This paper confirms that leadership member exchange differentiation can positively moderate the relationship between paradoxical leadership and work pressure perception.

[Antibodies persistence after revaccination with three doses of hepatitis B vaccine in non-responsive adults: results from 8-year follow-up study]

Objective: To evaluate the persistence of HBsAg-specific antibodies eight years after revaccination with hepatitis B vaccine (HepB) among adults who were non-responsive to primary immunization. Methods: From August to September 2009, rural communities in Zhangqiu district of Ji'nan city were selected as the study site. The subject's inclusion criteria were 18 to 49 years old, local resident population, without HBV infection history and HepB vaccination history, and good health status. Antibodies against hepatitis B surface antigen (anti-HBs) were detected in adults following the standard primary vaccination. Those who were non-responders (anti-HBs titer <10 mIU/ml) were revaccinated with three doses of HepB and included in the study. Blood samples were collected from all of them at one month (T₁), two years, four years, and eight years after revaccination. The three indexes of anti-HBs, hepatitis B surface antigen (HBsAg), together with antibody against hepatitis B core antigen (anti-HBc), were measured by chemiluminescence microparticle immunoassay (CMIA). Results: The proportion of subjects with anti-HBs titers ≥10 mIU/ml was 85.12% (549/645) at T₁, 60.60% (283/467) at two years, 55.90% (199/356) at four years and 55.09% (222/403) at eight years after revaccination. The first two years' annual decline rates, three to four years and five to eight years, were 15.62%, 3.96%, and 0.36%. The GMC of anti-HBs was 153.92 mIU/ml at T₁, 21.43 mIU/ml at two years, 15.02 mIU/ml at four years, and 13.68 mIU/ml at eight years. In the first two years, three to four years and five to eight years, the annual decline rate of GMC was 62.69%,16.28%, and 2.31%, respectively. Multivariable analysis showed that the titer of anti-HBs at T₁ was independently associated with the persistence of anti-HBs at eight years after revaccination. Compared with anti-HBs titer <100 mIU/ml , those whose anti-HBs titers were 100-mIU/ml and ≥1 000 mIU/ml at T₁ had a higher positive rate of anti-HBs (OR=14.13, P<0.001; OR= 62.91, P<0.001) and a higher probability of anti-HBs titer (β=1.88, P<0.001; β=3.24, P<0.001) at 8 years after revaccination. Nobody was found seroconversion of HBsAg, and the anti-HBc positive rate was 14.14% (57/403). Conclusions: Following revaccination with three doses of HepB in adults who were non-responsive to primary immunization, anti-HBs titers declined rapidly within the first four years. They then maintained a stable level after the fifth year. More than half still kept anti-HBs protective titer at eight years after revaccination. The immunity persistence was associated with anti-HBs titer at one month after revaccination.

Mechanism and Selectivity of Cyclopropanation of 3-Alkenyl-oxindoles with Sulfoxonium Ylides Catalyzed by a Chiral N,N'-Dioxide-Mg(II) Complex

The mechanism and stereoselectivity of an asymmetric cyclopropanation reaction between 3-alkenyl-oxindole and sulfoxonium ylide catalyzed by a chiral N,N'-dioxide-Mg(II) complex were explored using the B3LYP-D3(BJ) functional and the def2-TZVP basis set. The noncatalytic reaction occurred via a stepwise mechanism, with activation barriers of 21.6-23.5 kcal mol^-1. The C₂-C_α bond formed followed by the carbanion S_N2 substitution, constructing a three-membered ring in spiro-cyclopropyl oxindoles, accompanied by the release of dimethylsulfoxide. The electron-withdrawing N-protecting t-butyloxy carbonyl (Boc) and acetyl (Ac) groups in isatin enhanced the local electrophilicity of the C2 atom and the repulsion between the two COPh groups in the reactants, contributing to high reactivity as well as good diastereoselectivity results. The N-Boc-3-phenacylideneoxindole coordinated to the chiral ligand (L-PiPr₂) in a bidentate fashion, forming a hexacoordinate-Mg(II) complex as the reactive species. The origin of enantioselectivity was from the shielding effect of 2,6-diisopropylphenyl groups in the ligand toward the si-face of oxindole. The repulsion between the SO(CH₃)₂ and COPh groups in 3-alkenyl-oxindole and the neighboring ortho-iPr group in the ligand directed the re-face of ylide to attack the re-face of oxindole preferably, contributing to the high diastereoselectivity of the product. A metal-ion-ligand matching relationship was important for a good asymmetric induction effect of the chiral N,N'-dioxide-metal catalyst. A large chiral cavity in the Zn(II) catalyst weakened the shielding effect of 2,6-diisopropylphenyl groups in the ligand toward the prochiral face of oxindole, leading to inferior enantioselectivity observed in the experiment.

Fabrication of Ag/TiO2 Cotton Fabric to Enhance Photocatalytic Degradation of Anionic Dye

Ag/TiO2 composite fabric was prepared by coprecipitation with TiCl4 as a titanium source and AgNO3 as a silver source. The samples were characterized by scanning electron microscope (SEM), thermogravimetric analyzer (TG) and Fourier transform infrared spectrometer (FTIR). The photocatalytic activity of synthetic fabrics was measured by the degradation of anion dyes under ultraviolet light. The effects of silver loading concentration, fabric area, initial concentration, and photocatalytic time on photocatalytic activity were investigated. The experimental results showed that the degradation rate of Ag/TiO2 composite fabric on anion dyes could reach 70.76% in 50 minutes, indicating that the prepared Ag/TiO2 composite fabrics had high photocatalytic activity.

[Effects of different calcium intakes on metabolism in healthy adults under strict dietary intervention]

Objective: To explore the effect of different calcium intakes on metabolism in healthy adults with traditional Chinese dietary pattern. Methods: A total of 64 college students (32 males and 32 females) were recruited from the School of Public Health, Harbin Medical University from September to October 2015. A prospective, randomized, double-blind, placebo-controlled trial design (RCT trial) was used to strictly control the diet of the volunteers through meal preparation, so that the background of the experimental and the control group was exactly the same. In our study, 64 healthy adults were randomly divided into two groups (calcium supplementation and control). The two groups were given the same diet every day. One group was given 400 mg/d of calcium supplementation, which was close to the recommended intake in China (800 mg/d); the other group was given pacebo, the average calcium intake was close to the average intake of Chinese (400 mg/d), calcium intervention lasted for 35 days. Serum and urine samples from pre-intervention, mid-intervention, and post-intervention were collected for metabolomics studies and detection of serum hormone levels and biochemical indicators. PCA and PLS-DA were used to compare the differences in serum and urine metabolites. After adjusting for age and BMI, the differences of hormones [parathyroid hormone, 1, 25(OH)₂D₃] and biochemical indicators were compared by repeated measurement variance analysis. Results: The 64 subjects were aged 23-28 years, including 32 males and 32 females. The baseline characteristics of the calcium supplementation group and the control group were balanced. The results showed that there were no significant differences in blood and urine metabolites, metabolic hormone [parathyroid hormone, 1, 25(OH)₂D₃] levels and biochemical indicators(serum Ca, serum P, glycolipid metabolism and hepatorenal function indicators)between the calcium supplementation group and control group at each time point throughout the trail (P>0.05). Conclusion: No health hazards associated with calcium deficiency was observed in healthy adults in the short term at current calcium intake level (300-400 mg/d).

[Identification of Synthetic Cannabinoid 5F-EDMB-PICA in Suspicious Herbal Products]

Objective To study the qualitative analysis strategy for unknown synthetic cannabinoid in the suspicious herbal product when no reference substance is available. Methods The synthetic cannabinoid in herbal blend was extracted with methanol. The extract was concentrated by rotary evaporator and separated and purified by preparative liquid chromatography, to obtain high purity synthetic cannabinoid sample. Gas chromatography-mass spectrometry （GC-MS）, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-QTOF-MS） and nuclear magnetic resonance （NMR） were used to determine the structure of the prepared compound. Results High purity unknown sample （10 mg） was obtained by preparative liquid chromatography. The sample was analyzed by GC-MS, UPLC-TOF-MS and NMR, and through spectrum analysis, the unknown synthetic cannabinoid was determined as 5F-EDMB-PICA. Conclusion The method to extract unknown synthetic cannabinoid from low content herbal products by preparative liquid chromatography was established, and the structure of the unknown sample was identified by comprehensive use of GC-MS, UPLC-QTOF-MS and NMR. The information will assist forensic laboratories in identifying this substance or other compounds with similar structures in their casework.

Alternative polyadenylation events differ dramatically between Tongcheng and Large White pigs in response to PRRSV infection

Alternative polyadenylation (APA) is a widespread post-transcriptional regulation mechanism that increases the biological complexity of transcriptome and proteome. However, it is unclear whether APA regulation plays a role in genetic resistance to porcine reproductive and respiratory syndrome virus (PRRSV). Here, we reported genome-wide APA regulation of porcine alveolar macrophages in PRRSV-resistant Tongcheng (TC) pigs and PRRSV-susceptible Large White (LW) pigs upon PRRSV infection. Using 3' mRNA sequencing strategy, we detected 75 981 high-quality APA sites in porcine alveolar macrophages of TC and LW pigs. Furthermore, 1202 and 1089 differentially expressed APA sites, as well as 79 and 117 untranslated region-APA switching genes were identified in TC pigs and LW pigs upon PRRSV infection respectively. The APA events in TC pigs and LW pigs were involved in different biological pathways, while APA events in TC pigs are directly associated with the immune response to PRRSV infection. In addition, we identified genetic variations affecting polyadenylation signal between TC pigs and LW pigs. These findings would provide helpful information on APA regulation for further understanding of genetic resistance to PRRSV.