Identification and characterization of circRNAs in maize seedlings under deficient nitrogen

Here, deep sequencing results of the maize transcriptome in leaves and roots were compared under high-nitrogen (HN) and low-nitrogen (LN) conditions to identify differentially expressed circRNAs (DECs). Circular RNAs (circRNAs) are covalently closed non-coding RNA with widely regulatory potency that has been identified in animals and plants. However, the understanding of circRNAs involved in responsive nitrogen deficiency remains to be elucidated. A total of 24 and 22 DECs were obtained from the leaves and roots, respectively. Ten circRNAs were validated by divergent and convergent primers, and 6 DECs showed the same expression tendency validated by reverse transcriptase-quantitative PCR. Integrating the identified differentially expressed miRNAs, 34 circRNAs could act as miRNA decoys, which might play important roles in multiple biological processes, including organonitrogen compound biosynthesis and regulation of the metabolic process. A total of 51 circRNA-parent genes located in the genome-wide association study identified loci were assessed between HN and LN conditions and were associated with root growth and development. In summary, our results provide valuable information regarding further study of maize circRNAs under nitrogen deficiency and provide new insights into screening of candidate genes as well as the improvement of maize regarding nitrogen deficiency resistance. CircRNA-miRNA-mRNA co-expression networks were constructed to explore the circRNAs that participated in biological development and nitrogen metabolism.

Identification of a pyroptosis-associated long non-coding RNA signature for predicting the immune status and prognosis in skin cutaneous melanoma

OBJECTIVE

Pyroptosis is correlated with programmed tumor cell death and the tumor microenvironment. However, the prognostic value of pyroptosis-associated long non-coding RNAs (lncRNAs) in skin cutaneous melanoma (SKCM), a malignant tumor with a poor prognosis, has not been established.

PATIENTS AND METHODS

In this study, expression profiles and clinical data of patients with SKCM were downloaded from The Cancer Genome Atlas (TCGA) database to identify differentially expressed pyroptosis-related lncRNAs related to overall survival. A lncRNA risk signature was constructed by Cox regression analyses and its prognostic value was evaluated. Associations between the lncRNA signature and immune status, immune microenvironment, tumor stemness, immune checkpoints, and m6A-related genes were further evaluated.

RESULTS

Twenty-two pyroptosis-related lncRNAs were identified and incorporated into a prognostic risk signature. The signature was significantly correlated with overall survival, tumor growth, and metastasis in SKCM. The signature demonstrated better diagnostic accuracy than conventional clinicopathological characteristics. A gene set enrichment analysis indicated that the risk signature was enriched in several immune-related pathways. Furthermore, the risk signature was significantly correlated with the immune microenvironment, immune cell infiltration, and immune subtypes, as well as tumor stem cells and some m6A-related genes. The lncRNA expression levels were also significantly related to responses to several anti-tumor drugs. Finally, a nomogram based on the risk score was established.

CONCLUSIONS

Overall, a risk signature based on 22 pyroptosis-associated lncRNAs was generated, providing a novel perspective on the determinants of prognosis and survival in SKCM and a basis for the development of individualized treatments.

Direct measurement of the PSF for Coulomb delocalization - a reconsideration

An interpretation of Coulomb delocalization, which limits the spatial resolution of inelastic TEM or STEM images, is given. We conclude that the corresponding point spread function cannot be measured as a broadening of a STEM probe.

The efficacy and safety of dupilumab in Chinese patients with moderate-to-severe atopic dermatitis: a randomized, double-blind, placebo-controlled study

BACKGROUND

Dupilumab is an antibody against interleukin 4 receptor α, used in treating atopic dermatitis (AD).

OBJECTIVES

To evaluate the efficacy and safety of dupilumab in adult Chinese patients with moderate-to-severe AD.

METHODS

In this randomized, double-blind, placebo-controlled, parallel-group, phase III study, conducted between December 2018 and February 2020, patients with AD received dupilumab (300mg) or placebo once every 2 weeks for 16 weeks, and were followed up for 12 weeks. The primary efficacy endpoint was the proportion of patients with both Investigator's Global Assessment (IGA) score of 0-1 and a reduction from baseline of ≥2 points at week 16.

RESULTS

Overall, 165 patients (mean age: 30.6 years; 71.5% male) were randomized: 82 to dupilumab and 83 to placebo. At week 16, 26.8% of patients in the dupilumab group and 4.8% of patients in the placebo group achieved the primary endpoint (difference, 22.0%; 95% confidence interval [CI], 11.37-32.65%; p<0.0001). Compared with placebo, higher proportions of patients in the dupilumab group achieved ≥75% reduction in the Eczema Area and Severity Index score (57.3% vs 14.5%; difference, 42.9%; 95% CI, 29.75-55.97%; p<0.0001) and had ≥3-point (52.4% vs 9.6%; difference, 42.8%; 95% CI, 30.26-55.34%; p<0.0001) and ≥4-point (39.0% vs 4.8%; difference, 34.2%; 95% CI, 22.69-45.72%; p<0.0001) reductions in weekly average daily peak daily pruritus numerical rating scale scores. The incidence of TEAEs during the treatment period was similar in the two groups. The incidence of conjunctivitis, allergic conjunctivitis, and injection site reaction was higher in the dupilumab group than in the placebo group.

CONCLUSIONS

In adult Chinese patients, dupilumab was effective in improving the signs and symptoms of AD and demonstrated a favorable safety profile.

Analysis of neurotransmitters associated with neuropsychiatric status in workers following lead exposure

OBJECTIVE

To explore the correlation between neuropsychiatric status and blood neurotransmitter in lead workers, and to provide theoretical basis for the prevention and treatment of lead workers.

SUBJECTS AND METHODS

The study applied cross-sectional survey, 74 occupational lead exposed workers in a battery factory in a city of Hebei province were selected as the lead exposed group, and 62 workers (non-lead workers) were selected as the control group. The occupational health symptoms questionnaire and health examination and POMS (Profile of Mood State, POMS) emotional test questionnaire were applied to investigate the nearly emotional status of the studied objects, ICP-MS was used to determine the blood lead level of all subjects, HPLC (High performance liquid chromatography, HPLC) was applied to determine the concentration of neurotransmitter in peripheral blood of all studied subjects, and all results were applied the Pearson's correlation analysis.

RESULTS

The blood lead concentration of the lead workers group (163.23±40.77 ug/L) was significantly higher than that in the control group (43.62±14.50 ug/L), and the difference was statistically significant. From the analysis of neuropsychiatric status, the neurological symptoms in the lead workers group were higher than that in the control group, among which the symptoms of sleep disturbance, dizziness, fatigue, numbness of limbs and dampness and coldness of limbs were more obvious. Among the symptoms of digestive system, the incidence of abdominal pain, abdominal distension, constipation and nausea and vomiting were higher. According to the POMS emotion questionnaire, the scores of 5 negative emotions and 1 positive emotion in the lead exposure group were higher than that in the control group, and the difference was statistically significant. Related to the control group, the concentration of neurotransmitters such as DA, 5-HT, GABA, Gly, Trp and Glu were statistically decreased, p<0.001. There was a negative correlation between neurotransmitters in peripheral blood and blood lead levels in lead workers, among which 5-HT had the greatest correlation with lead levels (r=-0.569, p<0.001). 5-HT and Trp were significantly correlated with tension-anxiety (T), depression-depression (D), anger-hostility (A), Vigor-hyperactivity (V), fatigue-inertia (F), and confusion-confusion (C). 5-HT, Trp and GABA were significantly correlated with the survey symptoms, among which, the sleep disorder, constipation and fatigue had most significantly positive correlation with 5-HT or Trp, r-value was respectively 0.373, 0.233 and 0.563.

CONCLUSIONS

Lead exposure not only causes the alteration of neuropsychiatric behavior of lead workers, but also changes gastrointestinal symptoms. Serotonin may be involved as the main neurotransmitter synthesized in intestinal, and the synthesis and metabolism may be regulated by intestinal flora.

Expression levels of plasma miRNA-21 and NT-proBNP in children with Kawasaki disease and their clinical significance

OBJECTIVE

The purpose of this study was to detect the expression levels of plasma microRNA-21 (miRNA-21) and NT-proBNP (N-terminal prohormone of brain natriuretic peptide) in children with Kawasaki disease (KD), as well as their clinical significance.

PATIENTS AND METHODS

Children with KD (n=100) who were treated in our hospital from June 2017 to May 2019 were included. In the same period, non-KD children with febrile diseases were included as controls. Plasma levels of miRNA-21 and NT-proBNP were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and electrochemiluminescence, respectively. Then, the relationship between miRNA-21 and NT-proBNP in children with KD was analyzed by Pearson's correlation test. Potential factors influencing KD were analyzed by Multivariate logistic regression test. Finally, receiver operating characteristic (ROC) curves were depicted to assess the diagnostic potentials of miRNA-21 and NT-proBNP in KD.

RESULTS

The results showed that miRNA-21 and NT-proBNP levels were higher in children with KD. Plasma level of miRNA-21 was positively correlated with NT-proBNP level in children with KD. Besides, both miRNA-21 and NT-proBNP were risk factors influencing the onset of KD. According to ROC curves, the sensitivity and specificity of miRNA-21 in diagnosing KD was 83% and 89%, respectively (AUC=0.9212, 95% CI: 0.8809-0.9614, cut-off value=1.985). NT-proBNP also displayed diagnostic potential in KD (AUC=0.9788, 95% CI: 0.9630-0.9946, cut-off value=265.6, sensitivity=88%, specificity=95%).

CONCLUSIONS

MiRNA-21 and NT-proBNP are upregulated in plasma of children with KD. They are positively correlated with each other and serve as risk factors for KD. Both of them can be utilized as indicators of auxiliary diagnosis in KD.

Study of PWR hot leg creep rupture and RCS depressurization strategy during an SBO accident

Preventing the leakage of radioactive materials is important to nuclear safety. During a station blackout accident in pressurized water reactors, the hot leg creep rupture caused by hot leg countercurrent flow occurs before the reactor pressure vessel failure that caused by lower head rupture. The secondary fission products barrier is lost after hot leg creep rupture. An analysis for this phenomenon was done using the Modular Accident Analysis Program version 4.0.4 code. A station blackout accident for CPR1000 is simulated and the occurrence and influence of hot leg creep rupture phenomenon are analyzed in detail. After that, a sensitivity analysis of the opening of different pressurizer pilot-operated relief valves at five minutes after entering severe accident management guideline (before the hot leg creep rupture occurs) is studied. The results show that reactor pressure vessel failure time can be extended by at least 4 h if at least one pilot-operated relief valve is opened and direct containment heating phenomenon can be eliminated if at least two pilot-operated relief valves are opened.

[Relapse of ankylosing spondylitis and its predictors after withdrawal of tumor necrosis factor-α inhibitors: a 52-week follow-up study]

OBJECTIVE

To investigate the recurrence of ankylosing spondylitis (AS) that has been relieved by standard-dose adalimumab (ADA) after dose reduction or withdrawal of tumor necrosis factor-α inhibitor (TNFi) and explore the factors that predict AS occurrence.

OBJECTIVE

This study was conducted among 63 patients with AS who reduced the dose of or discontinued TNFi after completing at least 12 treatment cycles with ADA (40 mg/2 weeks) to achieve ASAS20 improvement with a BATH disease activity index (BASDAI) < 4 for more than 8 weeks. The patients were followed up every 12 weeks for a total of 52 weeks, and the recurrence of AS, changes of BASDAI, C-reactive protein (CRP)-based disease activity score (ASDASCRP), low back pain (LBP) score, Bath Ankylosing Spondylitis Metrology Index (BASMI), CRP and ESR were recorded and analyzed. Cox regression model and ROC curve analyses were performed to analyze the risk factors of AS relapse after dose reduction or discontinuation of TNFi.

OBJECTIVE

Of the 63 patients enrolled, 57 completed the follow-up study, among whom 22 (38.6%) patients experienced AS relapse within 52 weeks, with a median clinical recurrence time of 31 weeks. The recurrence rate of AS was significantly higher in patients with complete withdrawal of medications (89.0%) than in those with TNFi dose reduction and TNFi discontinuation (P < 0.001), and did not differ significantly between the latter two groups of patients (χ²= 0.071, P=0.791). The Cox regression model showed that a high baseline LBP score (HR=1.438, P=0.027) and a high BASMI score (HR=1.29, P=0.049) were the risk factors for AS recurrence after TNFi dose reduction or discontinuation, while maintenance of medication during follow-up was a protective factor (HR=0.209, P=0.001). ROC curve analysis showed that the combination of baseline LBP score, BASMI and medication during follow-up had a good predictive value for AS relapse (AUC=0.819) with a sensitivity of 0.772 and a specificity of 0.718.

OBJECTIVE

Dose reduction or discontinuation of TNFi is associated with a high recurrence rate of AS that has been relieved by TNFi treatment. A high LBP score, a high BASMI score and discontinuation of maintenance medication are the risk factors for AS recurrence in patients after dose reduction or withdrawal of TNFi.

POS0754 DEVELOPMENT OF A RISK PREDICTION MODEL FOR VENOUS THROMBOEMBOLISM IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: THE SLE-VTE SCORE

Background:

Patients with systemic lupus erythematosus (SLE) have a substantially increased risk of venous thromboembolism (VTE). An individual VTE risk assessment is important to ensure that all patients are assessed and given adequate thromboprophylaxis.

Objectives:

We conducted this study to develop a risk score for VTE in patients with SLE.

Methods:

Patients with SLE who participated in the Chinese SLE Treatment and Research group were enrolled in this study. Patient baseline information and clinical laboratory indicators were obtained, and VTE events were recorded every 3-6 months during follow-up visits. The risk prediction model was created and internally validated using the bootstrap methods, and a scoring system was established (Figure 1).

Figure 1.

Flow chart of study design.

Results:

Out of 4,502 patients included in this study, 135 had a VTE event. After univariate analysis and Lasso regression, the following 11 variables were identified and included in the risk prediction model: male sex, age, BMI ≥25 kg/m2, hyperlipidemia, hypoalbuminemia, hsCRP>3 mg/L, renal involvement, nervous system involvement, anti-β2-glycoprotein I antibody positivity, lupus anticoagulant positivity, and no use of hydroxychloroquine. The AUC for the SLE-VTE score (Table 1) was 0.947 (95% CI, 0.9249-0.9694). The SLE-VTE score’s sensitivity and specificity with the optimal cutoff value of 13 were 0.919 and 0.881, respectively. The SLE-VTE score was superior to the GAPSS system in predicting the risk of VTE in patients with SLE (AUC= 0.947 vs. 0.680, P< 0.001; integrated discrimination improvement (IDI)= 0.6652, P< 0.001; net reclassification improvement (NRI)= 0.6652, P< 0.001).

Table 1.

Final multivariable analysis for venous thromboembolism risk in patients with SLE

β coefficientsOdds ratio* (95% CI)P-valuePoints in scoring systemMale0.6211.86(0.953-3.503)0.0612Age at study entry(≥50)0.8372.308(1.339-3.915)0.0023BMI02(kg/m20.7922.209(1.333-3.627)0.0023Hyperlipemia0.8382.313(1.246-4.166)0.0063Hypoalbuminemia2.1638.697(5.185-14.794)< 0.0017hsCRP>3 mg/L1.4524.272(2.618-6.968)< 0.0015Anti β2GPI1.0132.754(1.543-4.853)0.0013LA1.5594.752(2.799-8.072)< 0.0015Nervous system2.38210.832(6.163-18.998)< 0.0018Lupus nephritis0.8352.305(1.414-3.756)0.0013No use of hydroxychloroquine1.7715.876(3.722-9.401)< 0.0016

BMI: body mass index; hsCRP: Hypersensitive c-reactive protein; ACL: anticardiolipin, antiβ2GPI: anti-β2-glycoprotein I, LA: lupus anticoagulantm;

Values in bold are statistically significant at p <0.05.

Conclusion:

Various factors are related to the occurrence of VTE in patients with SLE. The proposed SLE-VTE risk score can accurately predict the risk of VTE and help identify SLE patients with a high risk of VTE who may benefit from thromboprophylaxis.

References:

[1]Ramirez GA, Efthymiou M, Isenberg DA, Cohen H. Under crossfire: thromboembolic risk in systemic lupus erythematosus. Rheumatology. 2018;58:940-952.

[2]Chung WS, Lin CL, Chang SN, Lu CC, Kao CH. Systemic lupus erythematosus increases the risks of deep vein thrombosis and pulmonary embolism: a nationwide cohort study. J Thromb Haemost. 2014;12:452-458.

[3]Liew NC, Alemany GV, Angchaisuksiri P, et al. Asian venous thromboembolism guidelines: updated recommendations for the prevention of venous thromboembolism. Int Angiol. 2017;36:1.

[4]Savino S, Giovanni S, Veronica M, Dario R, Khamashta MA, Laura BM. GAPSS: the Global Anti-Phospholipid Syndrome Score. Rheumatology. 2013:8.

[5]Konstantinides SV, Meyer G, Becattini C, et al. 2019 ESC Guidelines for the diagnosis and management of acute pulmonary embolism developed in collaboration with the European Respiratory Society (ERS). Eur Heart J. 2020;41:543-603.

[6]Moghadamyeghaneh Z, Hanna MH, Carmichael JC, Nguyen NT, Stamos MJ. A Nationwide Analysis of Postoperative Deep Vein Thrombosis and Pulmonary Embolism in Colon and Rectal Surgery. J Gastrointest Surg. 2014;18:2169-2177.

Disclosure of Interests:

None declared

AB0197 EFFICACY AND SAFETY OF HLX01 COMBINED WITH METHOTREXATE IN CHINESE PATIENTS WITH MODERATELY TO SEVERELY ACTIVE RHEUMATOID ARTHRITIS WHO HAD INADEQUATE RESPONSES TO METHOTREXATE: RESULTS OF A RANDOMISED, DOUBLE-BLIND, PLACEBO-CONTROLLED PHASE 3 STUDY

Background:

Rituximab is an effective therapy for rheumatoid arthritis (RA) patients with inadequate responses to methotrexate (MTX)1, 2. However, it has not been registered or approved in China for the treatment of RA by far. HLX01, an approved rituximab biosimilar (demonstrated in Chinese patients with diffuse large B-cell lymphoma)3, is thus evaluated in this study for the benefits of Chinese RA patients.

Objectives:

This study aimed to evaluate the efficacy and safety of HLX01 plus MTX versus placebo plus MTX in Chinese patients with active RA who had inadequate responses to MTX.

Methods:

This was a randomised, double-blind, placebo-controlled phase 3 study conducted in China (NCT03522415). Eligible patients were randomised 2:1 to receive intravenous infusion of 2×1000 mg HLX01 or placebo on day 1 and day 15. Patients with inadequate responses at week 16 and 20 were allowed to receive rescue treatments. Patients were retreated with or switched to receive (if initially assigned to placebo) 2×1000 mg rituximab at the first day of week 24 and 26. The primary endpoint of this study was the American College of Rheumatology criteria (ACR) 20 response at week 24. Secondary efficacy endpoints were evaluated at week 12, 24, 36 and 48. The safety, pharmacokinetics, pharmacodynamics and immunogenicity of HLX01 were observed and analyzed throughout the study.

Results:

Between May 28, 2018 and Sep 11, 2020, a total of 275 patients (ITT set) were randomised and 263 patients without major protocol deviations were included in per-protocol set (PPS). At week 24, HLX01 showed statistically superior efficacy (p <0.001) to placebo (ACR20: 60.7% vs 35.9% in ITT set, 60.3% vs 37.1% in PPS). Secondary efficacy endpoints were also significantly improved in HLX01 group compared with placebo (Table 1). The overall incidence of serious treatment emergent adverse events (TEAEs), adverse drug reactions (ADRs), and TEAEs leading to drug discontinuation were similar among treatment groups, with the most common TEAE been upper respiratory tract infection before (18.1% vs 18.5%) or after (13.0% vs 12.3%) week 24. Serum concentrations, immunogenicity and pharmacodynamics were similar between HLX01 and placebo groups.

Table 1.

Results of secondary efficacy endpoints at week 12, 24, 36 and 48 in ITT set.

DurationSecondary efficacy endpointsACR20 (%)ACR50 (%)ACR70 (%)DAS28-CRP(mean)HAQ-DI(mean)HLX01PlaceboHLX01PlaceboHLX01PlaceboHLX01PlaceboHLX01PlaceboBaseline5.495.431.401.45Week 1248.132.621.910.94.45.43.894.471.021.22Week 2460.735.936.618.515.312.03.394.370.871.22Week 3660.148.946.431.532.217.42.883.510.710.97Week 4873.862.055.240.239.927.22.823.510.721.03

Conclusion:

Comparing with placebo plus MTX, HLX01 plus MTX showed significantly improved clinical outcomes and comparable safety profiles in Chinese patients with moderately to severely active RA who had inadequate responses to MTX, demonstrating HLX01 in combination with MTX as a well-tolerated, safe and efficient treatment option.

References:

[1]Emery P, Deodhar A, Rigby WF, et al. Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab’s Efficacy in MTX iNadequate rEsponders (SERENE)). Ann Rheum Dis. Sep 2010;69(9):1629-35. doi:10.1136/ard.2009.119933.

[2]Rubbert-Roth A, Tak PP, Zerbini C, et al. Efficacy and safety of various repeat treatment dosing regimens of rituximab in patients with active rheumatoid arthritis: results of a Phase III randomized study (MIRROR). Rheumatology (Oxford). Sep 2010;49(9):1683-93. doi:10.1093/rheumatology/keq116.

[3]Shi Y, Song Y, Qin Y, et al. A phase 3 study of rituximab biosimilar HLX01 in patients with diffuse large B-cell lymphoma. J Hematol Oncol. Apr 16 2020;13(1):38. doi:10.1186/s13045-020-00871-9.

Acknowledgements:

The authors would like to thank participants in this study and their families. They would also like to acknowledge other investigators and staff at all clinical sites and the members of the Independent Data Monitoring Committee.

Disclosure of Interests:

None declared

MiR-21-5p in macrophage-derived extracellular vesicles affects podocyte pyroptosis in diabetic nephropathy by regulating A20

OBJECTIVES

Podocyte pyroptosis, characterized by inflammasome activation, plays an important role in inflammation-mediated diabetic nephropathy (DN). Our study aimed to investigate whether miR-21-5p in macrophage-derived extracellular vesicles (EVs) could affect podocyte injury in DN.

METHODS

EVs were extracted after the treatment of RAW 264.7 (mouse macrophage line) with high glucose (HG). The podocyte pyroptosis was determined using the flow cytometry and the western blot. After the knockdown of miR-21-5p in HG-induced RAW264.7 cells, we injected the extracted EVs into DN model mice.

RESULTS

The level of miR-21-5p was higher in HG-stimulated macrophage-derived EVs than in normal glucose-cultured macrophage-derived EVs. The co-culture of EVs and podocytes promoted reactive oxygen species (ROS) production and activation of inflammatory in MPC5 cells (mouse podocyte line). However, restraint of miR-21-5p in EVs reduced ROS production and inhibit inflammasome activation in MPC5 cells, thereby reducing podocytes injury. Meanwhile, we found that miR-21-5p inhibited the A20 expression through binding with its 3'-untranslated regions in MPC5 cells. Further studies showed that A20 was also involved in the regulation of miR-21-5p of RAW 264.7-derived EVs on MPC5 injury. At the same time, it was also proved in the DN model mice that miR-21-5p in macrophage-derived EVs could regulate podocyte injury.

CONCLUSION

MiR-21-5p in macrophage-derived EVs can regulate pyroptosis-mediated podocyte injury by A20 in DN.

POS0833 A RETROSPECTIVE COHORT STUDY IN CHINESE PATIENTS WITH ADULT POLYMYOSITIS AND DERMATOMYOSITIS: RISK OF COMORBIDITIES AND SUBCLASSIFICATION USING MACHINE LEARNING

Background:

Idiopathic inflammatory myopathy (IIM), also known as myositis, refers to a group of heterogeneous disorders including polymyositis (PM), dermatomyositis (DM), inclusion body myositis and immune-mediated necrotising myopathy. Phenotype, pathogenesis, and prognosis vary due to multi-organ involvement and comorbidities. With the clinical application of MSAs, a new classification system for myositis was explored to reduce confusion between subgroups. But it is far from showing the full picture of myositis due to high heterogeneity. Therefore, it is necessary to systematically evaluate the relevant risk factors of myositis for ILD, other rheumatic diseases, and malignancy for better clinical vigilance. And further exploring the subclassification of myositis is critical.

Objectives:

To identify the risk factors in Chinese patients with adult polymyositis and dermatomyositis for their comorbidities and explore a subclassification system.

Methods:

Clinical records of 397 patients with idiopathic inflammatory myopathies were retrospectively reviewed. Logistic regression was used to identify potential risk factors for interstitial lung disease (ILD), other rheumatic diseases, and malignancy after bivariate analysis. Hierarchical clustering and decisional tree were utilized to identify subgroups and explore a subclassification system.

Results:

A total of 119 polymyositis and 191 dermatomyositis patients were included. Anti-PM/Scl, anti-Ro52, anti-aminoacyl-tRNA synthetase and anti-MDA5 (adjusted odds ratios (AOR)=4.779, 1.917, 5.092 and 7.714 respectively) antibodies were risks (p<0.05), whereas overlapping malignancy was protective (AOR=0.107; p=0.002) for ILD across polymyositis, dermatomyositis and the total group. In subgroup models, Raynaud’s phenomenon, arthralgia and semi-quantitative anti-nuclear antibody (AOR=51.233, 4.261, 3.047 respectively) were risks for other overlapping rheumatic diseases (p<0.05). For overlapping malignancy, male and anti-TIF1γ antibodies (AOR=2.533, 16.949) were risks (p<0.05), whereas disease duration and combination of ILD (AOR=0.954, 0.106) were protective in the total group (p<0.05); while anti-NXP2 antibodies were identified as risk factors (AOR=73.152; p=0.038) in polymyositis. Hierarchical clustering suggested a subclassification with 6 subgroups: malignancy overlapping dermatomyositis, classical dermatomyositis, polymyositis with severe muscle involvement, dermatomyositis with ILD, polymyositis with ILD, and overlapping of myositis with other rheumatic diseases according to the characteristics of grouped patients. Accuracy of the classification and regression trees model was 0.768 (95% CI 0.711 to 0.819) on training set and 0.633 (95%CI 0.499 to 0.754) on test set.

Conclusion:

Accompanying ILD, other rheumatic diseases and malignancy are strongly associated with clinical manifestation and myositis-specific or myositis-associated autoantibodies among Chinese polymyositis and dermatomyositis patients. The subclassification system proposed a more precise phenotype defining toward stratified treatments.

Acknowledgements:

The study was supported by the Natural Science Foundation of China [No. 81803932] and the Natural Science Foundation of Guangdong Province [No. 2018030310025 and 2017A030313868]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Disclosure of Interests:

None declared

The true incidence of chromosomal mosaicism after preimplantation genetic testing is much lower than that indicated by trophectoderm biopsy

STUDY QUESTION

What is the true incidence of chromosomal mosaicism in embryos analyzed by preimplantation genetic testing (PGT).

SUMMARY ANSWER

The true incidence of chromosomal mosaicism is much lower than we usually surmise.

WHAT IS KNOWN ALREADY

In recent years, contemporary methods for chromosome analysis, along with the biopsy of more than one cell, have given rise to an increased rate of chromosomal mosaicism detection after preimplantation genetic testing for aneuploidy. However, the exorbitant incidence of mosaicism represents a dilemma and imposes restrictions on the application of PGT treatment. Concern has been raised about the possibility that the incidence of chromosomal mosaicism is overestimated and quite a few of the results are false-positive errors. However, studies verifying the diagnosis of chromosomal mosaicism and assessing the true incidence of chromosomal mosaicism are limited.

STUDY DESIGN, SIZE, DURATION

A total of 1719 blastocysts from 380 patients who underwent PGT treatment were retrospectively analyzed to evaluate the typical incidence of mosaicism. Then 101 embryos donated by 70 couples were re-biopsied and dissected into three portions if available: trophectoderm (TE), inner cell mass (ICM), and the remaining portions. All the portions were tested using next-generation sequencing (NGS), and the results were compared to the original diagnosis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The setting for this study was a university-affiliated center with an in-house PGT laboratory. All samples were amplified with multiple annealing and looping-based amplification cycles (MALBACs) and the NGS was carried out on a Life Technologies Ion Proton platform.

MAIN RESULTS AND THE ROLE OF CHANCE

A clinical TE biopsy revealed an incidence of 11.9% for diploid-aneuploid mosaicism (DAM), 17.3% for aneuploid mosaicism (AM) and 29.1% in total. After rebiopsy, 94.1% whole-chromosome aneuploidies and 82.8% segmental-chromosome aneuploidies were confirmed in the embryos. As for the mosaic errors, only 32 (31.7%) out of 101 embryos presented with uniform chromosomal aberrations in agreement with the original biopsy results, 15 (14.8%) embryos presented with de novo chromosomal aberrations, and 54 (53.5%) embryos showed a euploid profile in all portions. Among the 32 uniform embryos, the true mosaicism was confirmed in only 4 cases, where a reciprocal chromosomal aberration was identified; 14 embryos presented with identical mosaicism, providing the moderate evidence for true mosaicism; and 14 embryos displayed uniform full aneuploidies in all portions of embryo, revealing a high-grade mosaicism or a false-negative diagnosis. Logistical regression analysis revealed that the concordance rate with ICM was associated with the type and level of mosaicism. The concordance rate of segmental-chromosome mosaicism was significantly lower than whole-chromosome mosaicism (adjusted Odds Ratio (aOR): 5.137 (1.061, 24.876), P = 0.042) and compared to DAM, the concordance rate of AM was significantly higher (aOR: 6.546 (1.354, 31.655), P = 0.019). The concordance rate also increased with increasing levels of mosaicism (P < 0.001).

LIMITATIONS, REASONS FOR CAUTION

This study was limited by a small sample size and the use of a single whole-genome amplification (WGA) method and NGS platform. These findings are only applicable to samples subjected to MALBAC amplification and Ion Proton platform, and studies involving larger sample sizes and multiple WGA methods and NGS platforms are required to prove our findings.

WIDER IMPLICATIONS OF THE FINDINGS

TE biopsy is reliable to detect whole-chromosome aneuploidies, but the ability to diagnose mosaicism is doubtful. More attention should be paid to false-positive and false-negative errors in NGS-based PGT, especially for laboratories using less stringent criteria for mosaicism classification (i.e. 20-80%), which might be subject to a much higher false-positive mosaicism rate in the practice.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by grants from the National Key R&D Program of China (No. 2016YFC1000206-5) and the National Natural Science Foundation of China (No. 81701509).

TRIAL REGISTRATION NUMBER

N/A.

203 Developing and Fine-Tuning Novel 3D-Printed Biodegradable Scaffolds to Promote Auricular Cartilaginous Regeneration for Surgical Implantation

Introduction

Microtia, a congenital cartilaginous defect, poses major challenges in cosmetic surgery. Biodegradable polymers promote chondrogenesis, with promises of seeding cells into synthetic-polymer-implants for surgical fixation. However, existing polymers used in auricular reconstruction present limitations including inflammation, fibrosis, and extrusion. This study aimed to modulate the mechanical properties of the novel polylactic-acid/polyhydroxyalkanoate (PLA/PHA) blend by 3D-printing and hence, evaluate its suitability to the auricular microenvironment in developing next-generation reconstructs.

Method

Digitally defined PLA/PHA scaffolds were free-form 3D-printed at various infill densities and thicknesses. Through tensile testing, tensile moduli, yield point, maximum strength, tensile toughness, and stiffness were calculated, alongside Finite Element Analysis (FEA) and contact angle tests. Finally, preliminary cell seeding was conducted.

Results

Increasing infill densities of PLA/PHA scaffolds from 30%-60% significantly increased tensile moduli, yield point and maximum strength (P &lt; 0.01). Tensile stiffness increased significantly with scaffold thicknesses between 1mm-2mm (P &lt; 0.05). Cell studies showed promising proliferative activity.

Conclusions

The mechanical properties and structural stiffness of 3D-printed PLA/PHA scaffolds can be significantly tailored by altering infill density and thickness, respectively. The digitally defined interconnected pores within printed PLA/PHA scaffolds reduce stiffness mismatches between surgical-synthetic polymers and auricular cartilage, potentially promoting cell migration and nutrition transportation in future reconstructs.

Spatial changes and driving variables of topsoil organic carbon stocks in Chinese croplands under different fertilization strategies

The effect of different fertilization strategies on changes in soil organic carbon (SOC) largely depends on the current status of a given agricultural region. We analysed the results of 90 long-term field trials (20-37 years) in Chinese croplands to determine the effects of fertilization strategies [i.e., no fertilizer (CK), chemical fertilizer (NPK), manure only (M) and manure plus chemical fertilizers (NPKM)] on soil organic carbon stock (SOC_s) at 0-20 cm depth in the North (NC), Northeast (NEC), Northwest (NWC) and South (SC) China. Compared with initial values, SOC_s increased by 24-68% and 24-74% under NPKM and M applications, respectively, over the experimental periods. Furthermore, final SOC_s under NPKM in NEC and NWC were significantly higher than those under other treatments, but there was no significant difference between NPKM and M in SC and no significant differences among fertilizer treatments in NC. Average SOC stock change rates (SOC_r) were positive under all treatments for all regions except for CK and NPK in NEC, which were negative. There were regional differences in treatment effects: all treatments showed significantly different rates in NC and NWC, whereas there were no significant differences between the M and NPKM in NEC and SC. Random forest (RF) modeling showed that among the selected variables initial SOC_s was the most important in accounting for differences in SOC_r, followed by soil bulk density, mean annual temperature and precipitation for all treatments. Soil total nitrogen content was also an important explanatory variable for SOC_r for CK and NPK, and soil pH for M. This study has highlighted the main driving variables of SOC change which can be of use in optimizing fertilization strategies, by taking account of the baseline SOC_s status and environmental factors for different regions, to minimize soil carbon emissions while maximizing carbon sequestration in soils.

Zhuyu Annao decoction promotes angiogenesis in mice with cerebral hemorrhage by inhibiting the activity of PHD3

Some traditional Chinese decoctions, such as Zhuyu Annao, exert favorable therapeutic effects on acute cerebral hemorrhage, hemorrhagic stroke, and other neurological diseases, but the underlying mechanism remains unclear. This study aimed to determine whether Zhuyu Annao decoction (ZYAND) protects the injured brain by promoting angiogenesis following intracerebral hemorrhage (ICH) and elucidate its specific mechanism. The effect of ZYAND on the nervous system of mice after ICH was explored through behavioral experiments, such as the Morris water maze and Rotarod tests, and its effects on oxidative stress were explored by detecting several oxidative stress markers, including malondialdehyde, nitric oxide, glutathione peroxidase, and superoxide dismutase. Real-time quantitative RT-PCR and WB were used to detect the effects of ZYAND on the levels of prolyl hydroxylase domain 3 (PHD3), hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF) in the brain tissues of mice. The effect of ZYAND on the NF-κB signaling pathway was detected using a luciferase reporter gene. A human umbilical cord vascular endothelial cell angiogenesis experiment was performed to determine whether ZYAND promotes angiogenesis. The Morris water maze test and other behavioral experiments verified that ZYAND improved the neurobehavior of mice after ICH. ZYAND activated the PHD3/HIF-1α signaling pathway, inhibiting the oxidative damage caused by ICH. In angiogenesis experiments, it was found that ZYAND promoted VEGF-induced angiogenesis by upregulating the expression of HIF-1α, and NF-κB signaling regulated the expression of HIF-1α by inhibiting PHD3. ZYAND exerts a reparative effect on brain tissue damaged after ICH through the NF-κB/ PHD3/HIF-1α/VEGF signaling axis.

[Speckle-type POZ protein up-regulates c-Jun protein expression and promotes proliferation and invasion of renal carcinoma cells]

OBJECTIVE

To investigate the effect of speckle-type POZ protein (SPOP) on proliferation, apoptosis, migration and invasion of renal cell carcinoma (RCC) and explore the potential mechanisms.

OBJECTIVE

Renal carcinoma cell lines (786-O, A704, and Caki-2) cultured in vitro were transfected with a SPOP-overexpressing plasmid, and the changes in proliferation of the cells were detected using colony formation and MTT assay; TUNEL assay was used to assess apoptosis of the cells. The changes in migration and invasion abilities of the cells were examined using wound healing assay and Transwell assay. The mRNA and protein levels of SPOP and c-Jun in the transfected cells were measured using real-time PCR and Western blotting.

OBJECTIVE

SPOP over-expression obviously promoted the proliferation, migration and invasion of 786-O, A704 and Caki-2 cells (P < 0.05). Compared with the control cells, 786-o and Caki-2 cells over-expressing SPOP exhibited significantly lowered apoptosis rates (P < 0.05). The results of real-time PCR demonstrated that the transfected cells did not show obvious changes in the mRNA level of c-Jun, but the protein expressions of SPOP and c-jun increased significantly as shown by Western blotting (P < 0.05).

OBJECTIVE

SPOP can promote proliferation, migration, and invasion and suppress apoptosis of renal carcinoma cells possibly by promoting the expression of c-Jun.

Retraction notice to "30MO ORIENT-3: A randomized, open-label, phase III study of sintilimab versus docetaxel in previously treated advanced/metastatic squamous non-small cell lung cancer (sqNSCLC)": [Annals of Oncology Volume 31, Supplement 7, December 2020, Page S1428]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article was retracted at the request of the authors. The authors of this abstract have advised that full agreement between authors and sponsors on publication of the abstract has not been reached and they are therefore unable to publish this data at present.