Persistent transcriptional changes in cardiac adaptive immune cells following myocardial infarction: New evidence from the re-analysis of publicly available single cell and nuclei RNA-sequencing data sets

INTRODUCTION

Chronic immunopathology contributes to the development of heart failure after a myocardial infarction. Both T and B cells of the adaptive immune system are present in the myocardium and have been suggested to be involved in post-MI immunopathology.

METHODS

We analysed the B and T cell populations isolated from previously published single cell sequencing data sets (PMID: 32130914, PMID: 35948637, PMID: 32971526 and PMID: 35926050), of the mouse and human heart, using differential expression analysis, functional enrichment analysis, gene regulatory inferences, and integration with autoimmune and cardiovascular GWAS.

RESULTS

Already at baseline, mature effector B and T cells are present in the human and mouse heart, having increased activity in transcription factors maintaining tolerance (e.g. DEAF1, JDP2, SPI-B). Following MI, T cells upregulate pro-inflammatory transcript levels (e.g. Cd11, Gzmk, Prf1), while B cells upregulate activation markers (e.g. Il-6, Il1rn, Ccl6) and collagen (e.g. Col5a2, Col4a1, Col1a2). Importantly, pro-inflammatory and fibrotic transcription factors (e.g. NFKB1, CREM, REL) remain active in T cells, while B cells maintain elevated activity in transcription factors related to immunoglobulin production (e.g. ERG, REL) in both the mouse and human post-MI heart. Notably, genes differentially expressed in post-MI T and B cells are associated with cardiovascular and autoimmune disease.

CONCLUSION

These findings highlight the varied and time-dependent dynamic roles of post-MI T and B cells. They appear ready-to-go and are activated immediately after MI, thus participate in the acute wound healing response. However, they subsequently remain in a state of pro-inflammatory activation contributing to persistent immunopathology.

[Association between congenital hypothyroidism and in-hospital adverse outcomes in very low birth weight infants]

Objective: To investigate the association between congenital hypothyroidism (CH) and the adverse outcomes during hospitalization in very low birth weight infants (VLBWI). Methods: This prospective, multicenter observational cohort study was conducted based on the data from the Sino-northern Neonatal Network (SNN). Data of 5 818 VLBWI with birth weight <1 500 g and gestational age between 24-<37 weeks that were admitted to the 37 neonatal intensive care units from January 1st, 2019 to December 31st, 2022 were collected and analyzed. Thyroid function was first screened at 7 to 10 days after birth, followed by weekly tests within the first 4 weeks, and retested at 36 weeks of corrected gestational age or before discharge. The VLBWI were assigned to the CH group or non-CH group. Chi-square test, Fisher exact probability method, Wilcoxon rank sum test, univariate and multivariate Logistic regression were used to analyze the relationship between CH and poor prognosis during hospitalization in VLBWI. Results: A total of 5 818 eligible VLBWI were enrolled, with 2 982 (51.3%) males and the gestational age of 30 (29, 31) weeks. The incidence of CH was 5.5% (319 VLBWI). Among the CH group, only 121 VLBWI (37.9%) were diagnosed at the first screening. Univariate Logistic regression analysis showed that CH was associated with increased incidence of extrauterine growth retardation (EUGR) (OR=1.31(1.04-1.64), P<0.05) and retinopathy of prematurity (ROP) of stage Ⅲ and above (OR=1.74(1.11-2.75), P<0.05). However, multivariate Logistic regression analysis showed no significant correlation between CH and EUGR, moderate to severe bronchopulmonary dysplasia, grade Ⅲ to Ⅳ intraventricular hemorrhage, neonatal necrotizing enterocolitis in stage Ⅱ or above, and ROP in stage Ⅲ or above (OR=1.04 (0.81-1.33), 0.79 (0.54-1.15), 1.15 (0.58-2.26), 1.43 (0.81-2.53), 1.12 (0.70-1.80), all P>0.05). Conclusion: There is no significant correlation between CH and in-hospital adverse outcomes, possibly due to timely diagnosis and active replacement therapy.

Self-Aggregation, Antimicrobial Activity and Cytotoxicity of Ester-Bonded Gemini Quaternary Ammonium Salts: The Role of the Spacer

Five ester-bonded gemini quaternary ammonium surfactants C₁₂-E_n-C₁₂ (n = 2, 4, 6), with a flexible spacer group, and C₁₂-B_m-C₁₂ (m = 1, 2), with rigid benzene spacers, were synthesized via a two-step reaction and analyzed. Furthermore, the effects of the spacer structure, spacer length and polymerization degree on the self-aggregation, antimicrobial activity and cytotoxicity of C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ and their corresponding monomer N-dodecyl-N,N,N-trimethyl ammonium chloride DTAC were investigated. The results showed that C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ had markedly lower critical micellar concentration (CMC) values and lower surface tension than DTAC. Moreover, the CMC values of C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ decreased with increasing spacer length. In the case of equivalent chain length, the rigidity and steric hindrance of phenylene and 1,4-benzenediyl resulted in larger CMC values for C₁₂-B_m-C₁₂ than for C₁₂-E_n-C₁₂. The antibacterial ability of C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ was assessed using Escherichia coli (E. coli) and Staphylococcus albus (S. aureus) based on minimum inhibitory concentrations (MICs). Furthermore, C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ exhibited higher antimicrobial activity than DTAC and had stronger function toward S. aureus than E. coli. The antimicrobial activity was enhanced by increasing the spacer chain length and decreased with the increased rigidity of the spacers. The cytotoxic effects of C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ in cultured Hela cells were evaluated by the standard CCK8 method based on half-maximal inhibitory concentration (IC₅₀). The cytotoxicity of C₁₂-E_n-C₁₂ and C₁₂-B_m-C₁₂ was significantly lower than alkanediyl-α,ω-bis(dimethyldodecylammonium) bromide surfactants and DTAC. The spacer structure and the spacer length could induce significant cytotoxic effects on Hela cells. These findings indicate that the five ester-bonded GQASs have stronger antibacterial activity and lower toxicity profile, and thus can be used in the pharmaceutical industry.

Syringe Paper-Based Analytical Device for Thiamazole Detection by Hedysarum Polysaccharides-Mediated Silver Nanoparticles

In this paper, silver nanoparticles (AgNPs) were successfully green-synthesized for the first time using Hedysarum polysaccharide (HPS) as a reducing agent, stabilizer, and modifier (HPS-AgNP). Thiamazole could induce the aggregation of HPS-AgNPs in the residue on a cellulose membrane. A syringe paper-based analytical device was creatively established to ensure the tightness, stability, and good repeatability of the test. The color information remaining on the cellulose membrane was converted into gray values using ImageJ software. Hence, the linear regression curve for thiamazole was established as y = 1 + 0.179x with a detection limit (LOD) of 24.6 nM in the relatively wide range of 0.1~10 μM. This syringe paper-based analytical device was successfully applied to the biological samples.

In situ H2 O2 Generation and Corresponding Pollutant Removal Applications: A Review

Catalytic hydrogen peroxide (H₂ O₂ ) generation from oxygen and water enables a sustainable environment to operate in an effective and green energy-to-chemical conversion way, which has attracted increasing interest in the fields of energy production and environment treatment. In light of this, tremendous progresses and developments have been made during the past decades in catalytic H₂ O₂ production for pollutant removal from three perspectives including photocatalysis, electrocatalysis or chemical activation. Herein, we critically review the state-of-the-art developments over various procedures of H₂ O₂ generation and its further application, with the existence of photocatalysts, electrocatalysts, and catalysts, respectively. Benefiting from extensively experimental and theoretical investigations, the performance and stability of H₂ O₂ generation and its utilization can be maneuvered by devising catalytic platform based on numerous catalysts with predominant electronic, chemical and physical properties, which endow the catalysts with efficient electrons transportation, abundant active sites, and sufficient oxygen adsorption for H₂ O₂ generation. Furthermore, this review also discusses the formation mechanism of H₂ O₂ by 2e-ORR and 2e-WOR, as well as its functional process of activating and removing pollutants, and summarizes the design principles of various catalysts by focusing on the formation of H₂ O₂ . We finally highlight the specific challenges and prospects related to the utilization of catalysts and envision the possible future development trends in the fields of pollutant removal.

PPMS: A framework to Profile Primary MicroRNAs from Single-cell RNA-sequencing datasets

MOTIVATION

Single-cell/nuclei RNA-sequencing (scRNA-seq) technologies can simultaneously quantify gene expression in thousands of cells across the genome. However, the majority of the noncoding RNAs, such as microRNAs (miRNAs), cannot currently be profiled at the same scale. MiRNAs are a class of small noncoding RNAs and play an important role in gene regulation. MiRNAs originate from the processing of primary transcripts, known as primary-microRNAs (pri-miRNAs). The pri-miRNA transcripts, independent of their cognate miRNAs, can also function as long noncoding RNAs, code for micropeptides or even interact with DNA, acting like enhancers. Therefore, it is apparent that the significance of scRNA-seq pri-miRNA profiling expands beyond using pri-miRNA as proxies of mature miRNAs. However, there are no computational methods that allow profiling and quantification of pri-miRNAs at the single-cell-type resolution.

RESULTS

We have developed a simple yet effective computational framework to profile pri-MiRNAs from single-cell RNA-sequencing datasets (PPMS). Based on user input, PPMS can profile pri-miRNAs at cell-type resolution. PPMS can be applied to both newly produced and publicly available datasets obtained via single cell or single-nuclei RNA-seq. It allows users to (i) investigate the distribution of pri-miRNAs across cell types and cell states and (ii) establish a relationship between the number of cells/reads sequenced and the detection of pri-miRNAs. Here, to demonstrate its efficacy, we have applied PPMS to publicly available scRNA-seq data generated from (i) individual chambers (ventricles and atria) of the human heart, (ii) human pluripotent stem cells during their differentiation into cardiomyocytes (the heart beating cells) and (iii) hiPSCs-derived cardiomyocytes infected with severe acute respiratory syndrome coronavirus 2.

Hypersensitive C-reactive protein-albumin ratio is associated with stroke-associated pneumonia and early clinical outcomes in patients with acute ischemic stroke

OBJECTIVES

We aimed to explore the association between the baseline hypersensitive C-reactive protein-albumin ratio (CAR) and stroke-associated pneumonia (SAP) during hospitalization and the short-term prognosis in patients with acute ischemic stroke (AIS).

METHODS

We enrolled 766 patients with AIS and collected their admission baseline characteristics, including their National Institutes of Health Stroke Scale score, CAR, age, atrial fibrillation, dysphagia, sex, stroke severity (A² DS² ) score, and other information. The occurrence of SAP within 7 days after stroke, length of hospital stay, and physical condition at discharge were also recorded. The patients' Modified Rankin Scale (mRS) scores and mortality 3 months after AIS were further evaluated at follow-up. All patients were divided into four groups based on the quartiles of the admission CAR (Q1 <1.3, Q2 1.3-3.7, Q3 3.7-9.3, Q4 ≥9.3).

RESULTS

During hospitalization, 92 (11.9%) patients were diagnosed with SAP. The patients with SAP had a higher CAR than the non-SAP patients (p < .001). In the multivariate-adjusted model, the patients in the Q3 and Q4 groups had a higher SAP risk (aOR was 5.21 and 17.72, p-trend < .001) than those in the lowest quartile. The area under the curve for the CAR's ability to predict SAP was 0.810 in the receiver operating characteristic curve analysis and had a similar predictive efficacy as the A² DS²  score (p <.05). The length of stay in the SAP group was almost the same as that in the non-SAP group, but the clinical outcomes were worse at discharge and at the 3-month follow-up in the SAP group. In addition, the patients in the higher CAR quartiles at admission were more likely to have poorer clinical outcomes.

CONCLUSIONS

Patients with AIS with a high CAR at admission are more likely to develop SAP during hospitalization and have poor short-term clinical outcomes. These findings might help to timely identify patients at high risk of SAP and provide a basis for further research on prophylactic antibiotic therapy.

Sensitive determination of tobramycin using homocystine capped gold nanoclusters as probe by second-order scattering

A novel photoluminescent Hcy-AuNCs has been developed through one-pot reduction method, to establish a tobramycin sensing by second-order scattering (SOS). Hcy-AuNCs could spontaneously assemble to small-scaled aggregation, resulting in remarkable intensity enhancement of scattered luminescence signals. The luminescence of Hcy-AuNCs could be clearly observed under ultraviolet lamp, when excited at 365 nm, a significant luminescent intensity at 741 nm was monitored in SOS spectra. The introduction of AuNPs would cause large-scaled aggregation of Hcy-AuNCs that was rapidly settled in the solution, resulting in the decrease of SOS intensity. Besides, the non-radiative energy transfer between AuNPs and Hcy-AuNCs would also reduce the luminescent intensity. However, the addition of tobramycin would cause the aggregation of AuNPs due to the electrostatic and covalent bonding between AuNPs and tobramycin, thus eliminating the interference of AuNPs. The luminescence of Hcy-AuNCs reappeared, exhibiting an optical response toward tobramycin. The good linearity was obtained in a wide range from 4 nM to 300 nM with a low detection limit of 0.27 nM. The selectivity was acceptable toward different types of antibiotics. Finally, the proposed method was successfully applied to the widely used tobramycin eye drops.

Human umbilical cord mesenchymal stem cell-derived exosomes carrying hsa-miRNA-128-3p suppress pancreatic ductal cell carcinoma by inhibiting Galectin-3

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignant tumors of the digestive system. Many patients are diagnosed at an advanced stage and lose eligibility for surgery. Moreover, there are few effective methods for treating pancreatic ductal cell carcinoma. Increasing attention has been given to microRNAs (miRNAs) and their regulatory roles in tumor progression. In this study, we investigated the effects of exosomes extracted from human umbilical cord mesenchymal stem cells (HUCMSCs) carrying hsa-miRNA-128-3p on pancreatic cancer cells.

METHODS

Based on existing experimental and database information, we selected Galectin-3, which is associated with pancreatic cancer, and the corresponding upstream hsa-miRNA-128-3p. We extracted HUCMSCs from a fresh umbilical cord, hsa-miRNA-128-3p was transfected into HUCMSCs, and exosomes containing hsa-miRNA-128-3p were extracted and collected. The effect of exosomes rich in hsa-miRNA-128-3p on pancreatic cancer cells was analyzed.

RESULTS

The expression of Galectin-3 in normal pancreatic duct epithelial cells was significantly lower than that in PDAC cell lines. We successfully extracted HUCMSCs from the umbilical cord and transfected hsa-miRNA-128-3p into HUCMSCs. Then we demonstrated that HUCMSC-derived exosomes with hsa-miRNA-128-3p could suppress the proliferation, invasion, and migration of PANC-1 cells in vitro by targeting Galectin-3.

CONCLUSION

Hsa-miRNA-128-3p could be considered as a potential therapy for pancreatic cancer. We provided a new idea for targeted therapy of PDAC.

Green synthesis, characterization of Radix Hedysari-mediated silver nanoparticles and their use for sensitive colorimetric detection of Pb2+ in the Yellow River medium

In this study, a safe, rapid, and environment-friendly green synthesis of silver nanoparticles using the alcohol extract of Radix Hedysari (RH-AgNPs) was developed, the alcohol extract of Radix Hedysari (RH) acted as the reducing agent, stabilizer, and modifier. The main components of RH were determined using high-performance liquid chromatography (HPLC). The particle size and morphology of RH-AgNPs were optimized and characterized by a series of techniques. The size distribution, zeta potential, element distribution, and crystalline nature of RH-AgNPs were all determined. It was indicated that RH-AgNPs showed great sensitivity for lead ion (Pb²⁺) detection with a limit of detection (LOD) of 1.5 μM with a wide range of 10-500 μM. The selectivity was also explored for common metal ions. RH-AgNPs were then applied to the detection of Pb²⁺ in spiked Yellow River samples, and the possible mechanism is based on the crosslinking reaction between the hydroxide radical, carboxylate radical and Pb²⁺.

PANa/Covalent organic framework composites with improved water uptake and proton conductivity

It is a challenge to effectively load proton carriers in COFs to improve their proton conductivity. Herein, we report a series of COF-based composites, PANa@UCOF-x (PANa: sodium polyacrylate, x: weight percentage of PANa), which were prepared by coating different proportions of superabsorbent PANa on the COF surface based on an in situ reaction strategy. Since PANa can greatly enhance the enrichment of water molecules in one-dimensional (1D) channels of COFs, these COF-based composites exhibit superprotonic conduction. At 80 °C and 95% relative humidity (RH), the proton conductivity of PANa@UCOF-10, PANa@UCOF-28 and PANa@UCOF-40 reaches 1.6 × 10^-2, 5.1 × 10^-2, and 1.1 × 10^-1 S cm^-1, respectively, which is 4-5 orders of magnitude higher than 7.4 × 10^-7 S cm^-1 of the original UCOF. This work not only develops a new method to improve the water content of the COF channels, but also proves the important role of ordered channels in constructing effective proton conduction pathways.

Increased admission serum total bile acids can be associated with decreased 3-month mortality in patients with acute ischemic stroke

BACKGROUND

Bile acids (BAs) not only play an important role in lipid metabolism and atherosclerosis but also have antiapoptotic and neuroprotective effects. However, few studies have focused on the relationship of the total bile acid (TBA) levels with the severity and prognosis of acute ischemic stroke (AIS).

OBJECTIVES

The aim of this study was to investigate the potential associations of the fasting serum TBA levels on admission with the stroke severity, in-hospital complication incidence and 3 -month all-cause mortality in patients with AIS.

METHODS

A total of 777 consecutive AIS patients were enrolled in this study and were divided into four groups according to the quartiles of the serum TBA levels on admission. Univariate and multivariate logistic regression analyses were used to explore the relationship between the fasting TBA levels and the stroke severity, in-hospital complications, and 3-month mortality in AIS patients.

RESULTS

Patients in group Q3 had the lowest risk of severe AIS (NIHSS > 10) regardless of the adjustments for confounders (P < 0.05). During hospitalization, 115 patients (14.8%) had stroke progression (NIHSS score increased by ≥ 2), and 222 patients (28.6%) developed at least one complication, with no significant difference among the four groups (P > 0.05). There was no significant difference in the incidence of pneumonia, urinary tract infection (UTI), hemorrhagic transformation (HT), gastrointestinal bleeding (GIB), seizures or renal insufficiency (RI) among the four groups (P > 0.05). A total of 114 patients (14.7%) died from various causes (including in-hospital deaths) at the 3-month follow-up, including 42 (21.3%), 26 (13.3%), 19 (9.9%) and 27 (13.9%) patients in groups Q1, Q2, Q3 and Q4 respectively, with significant differences (P = 0.013). After adjusting for confounding factors, the risk of death decreased (P -trend < 0.05) in groups Q2, Q3, and Q4 when compared with group Q1, and the OR values were 0.36 (0.16-0.80), 0.30 (0.13-0.70), and 0.29 (0.13-0.65), respectively.

CONCLUSIONS

TBA levels were inversely associated with the 3-month mortality of AIS patients but were not significantly associated with the severity of stroke or the incidence of complications.

Aluminum chloride induces G0/G1 phase arrest via regulating the reactive oxygen species-depended non-canonical STAT1 pathway in hFOB1.19 cells

Treatment with aluminum chloride (AlCl₃) suppresses the growth of osteoblastic cells; however, the molecular mechanisms underlying the impact of AlCl₃ on cell growth have not been fully characterized. In this study, we observed that exposure of hFOB1.19 cells to AlCl₃ arrested cells at G₀/G₁ phase by inducing p21 expression. Further studies indicated that AlCl₃ upregulated the phosphorylation level of signal transducer and activator of transcription 1 (STAT1) at serine 727 site (Ser727). By chromatin immunoprecipitation and electrophoretic mobility shift assay, we found that AlCl₃ promoted STAT1/DNA binding activity to p21 promoter, thus resulting in the upregulation of p21. Moreover, siRNA-mediated knockdown of STAT1 attenuated p21 level induced by AlCl₃. Notably, using hFOB1.19 cells stably expressing dominant-negative STAT1 (Ser727Ala), we demonstrated that phosphorylation of STAT1 at Ser727 site is required for p21-mediated cycle arrest induced by AlCl₃. Mechanism investigation indicated that AlCl₃ stimulated the phosphorylation of JNK, and administration of JNK inhibitor SP600125 prevented AlCl₃-induced G₀/G₁ arrest through suppressing the phosphorylation of STAT1. Notably, pretreatment with N-acetyl-cysteine, a reactive oxygen species scavenger, conferred a significantly inhibitory effect on AlCl₃-mediated activation of JNK/STAT1 signaling pathway. Taken together, our findings provide the molecular mechanism for G₀/G₁ arrest induced by AlCl₃ in osteoblastic cells.

Development and Application of a Reverse-transcription Recombinase-Aided Amplification Assay for Subgroup J Avian Leukosis Virus

Subgroup J Avian leukosis virus (ALV-J) is an important pathogen of poultry tumor diseases. Since its discovery, it has caused significant economic losses to the poultry industry. Thus, the rapid detection of molecular level with strong specificity is particularly important whether poultry are infected with ALV-J. In this study, we designed primers and probe for real-time fluorescent reverse-transcription recombinase-aided amplification assay (RT-RAA) based on the ALV-J gp85 sequence. We had established a real-time fluorescent RT-RAA method and confirmed this system by verifying the specificity and sensitivity of the primers and probe. In addition, repeatability tests and clinical sample regression tests were used for preliminary evaluation of this detection method. The sensitivity of established method was about 10¹ copies/μL, and the repeatability of the CV of the C_T value is 4%, indicating repeatability is good. Moreover, there was no cross-reactivity with NDV, IBV, IBDV, H9N2, MDV, and REV, and other avian leukosis virus subgroups, such as subgroups A, B, C, D, K and E. Importantly, the real-time fluorescent RT-RAA completed the test within 30 min at a constant temperature of 41°C. Forty-two clinical samples with known background were tested, and the test results were coincided with 100%. Overall, these results suggested that the real-time fluorescent RT-RAA developed in this study had strong specificity, high sensitivity, and good feasibility. The method is simple, easy, and portable, that is suitable for clinical and laboratory diagnosis, and provides technical support for the prevention and control of ALV-J.

[Effect of daily average temperature on the incidence of allergic rhinitis in Lanzhou]

Objective: To evaluate the effect of daily average temperature on the atteck of allergic rhinitis (AR) by analyzing the changes of the outpatient visits of AR in Lanzhou. Methods: The meteorological and air pollution data of Lanzhou City and the outpatient visits of AR in Departments of Otorhinolaryngology and head and neck surgery of The First Hospital of Lanzhou University, The Second Hospital of Lanzhou University and Gansu Provincial People's Hospital from 2013 to 2017 were collected to describe the meteorological factors, air pollutants and the outpatient visits of AR. The correlation among the three factors was then analyzed by Spearman rank correlation analysis. Using the distributed lag non-linear model, the relationship between daily average temperature and the number of daily outpatient visits of AR was studied and stratified by gender and age with the long-term trend, seasonal trend and other confounding factors controlled. Results: From 2013 to 2017, the outpatient visits of AR in the above three hospitals reached 20 008 person times. Daily average temperature in Lanzhou showed a non-linear correlation to the outpatient visits of AR, with a certain lag effect. When the daily average temperature was 22 ℃ and the cumulative lag was 21 days (lag 0-21 d), the relative risk (RR) peaked at 4.851 (95%CI: 3.986-5.904). The effect of relatively low temperature (2.3 ℃, P₂₅), relatively high temperature (19.8 ℃, P₇₅) and high temperature (25.5 ℃, P₉₅) on lag 0-21 d were the highest, which were 1.761 (95%CI: 1.375-2.255), 4.299 (95%CI: 3.574-5.171) and 3.656 (95%CI: 3.046-4.389), respectively. According to the stratified analysis, low and relatively low temperature had more significant effect on the outpatient visits of AR among women and people aged 0-14 years. When lag was 0-21 days, the RR value of low temperature for female outpatient visits of AR was 1.433 (95%CI: 1.105-1.860); the RR value of relatively low temperature for female outpatient visits of AR was 1.879 (95%CI: 1.460-2.419); the RR value of low temperature for AR outpatient visits for people aged 0-14 years was 1.511 (95%CI: 0.999-2.287), the RR value of relatively low temperature for AR outpatient visits for people aged 0-14 years was 2.051 (95%CI: 1.383-3.042). Relatively high temperature, on the other hand, had a more significant effect on men and people aged 15-59 years. High temperature had a greater impact on the number of AR outpatients in men and people aged 0-14 years. Conclusions: Temperature may be an important influencing factor of AR onset in Lanzhou. At relatively high temperature (19.8 ℃), the risk of AR outpatient visits is significantly increased, and the cumulative lagged effects are observed. The sensitivity of AR patients to temperature is different in different genders and ages.

Use of transanal drainage tube to prevent anastomotic leakage: intangible differences between the East and the West

Trans-anal drainage tube is used to reduce the rectal pressure, especially at the anastomotic site and thus to protect the anastomosis. Ideally it serves as and even may replace a diverting stoma. When compared to no treatment, the effectiveness of TDT seems confirmed based on the literature, but it remains uncertain whether TDT can replace the diverting stoma. Despite the insignificant tangible costs of TDT, it seems different cultures put varied weight on the intangible costs such as discomfort and pain to patients after surgery.

Two atypical gram-negative bacteria-binding proteins are involved in the antibacterial response in the pea aphid (Acyrthosiphon pisum)

The activation of immune pathways is triggered by the recognition of pathogens by pattern recognition receptors (PRRs). Gram-negative bacteria-binding proteins (GNBPs)/β-1,3-glucan recognition proteins (βGRPs) are a conserved family of PRRs in insects. Two GNBPs are predicted in the genome database of pea aphids; however, little is known about their functions in the aphid immune system. Here, we show that pea aphid GNBPs possess domain architectures and sequence features distinct from those of typical GNBPs/βGRPs and that their expression is induced by bacterial infection. Knockdown of their expression by dsRNA resulted in lower phenoloxidase activity, higher bacterial loads and higher mortality in aphids after infection. Our data suggest that these two atypical GNBPs are involved in the antibacterial response in the pea aphid, likely acting as PRRs in the prophenoloxidase pathway.

Abstract 669: A comprehensive single cell analysis of cancer-associated fibroblasts (CAFs) reveals subtypes with prognostic impact in pancreatic ductal adenocarcinoma

Introduction The presence of heterogeneity in cancer-associated fibroblasts (CAFs) of pancreatic ductal adenocarcinoma (PDAC) is well-known. The presence of mouse inflammatory CAFs (iCAFs) and myofibroblastic CAFs (myCAFs) were published earlier. Recently, we identified the first patient-derived sub-populations of CAFs (pCAFassigner) with different phenotypic and pathological characteristics. We demonstrated the presence of intra-tumoral heterogeneity in patients, differential sensitivity of CAF subtypes in co-cultures with cancer cells to existing PDAC treatment options and prognostic impact of these subtypes. The presence of antigen-presenting CAFs (apCAFs) in humans and mouse was introduced recently. However, a comprehensive, unbiased analysis is required to reconcile different CAF classifications and understand the prognostic significance of these subtypes for future clinical translation.

Methods Mouse and human PDAC single-cell RNA sequencing (scRNA-seq)-based suite of analyses were performed to assign CAFs into pCAFassigner and other subtypes. Enrichment (hypergeometric) and differential gene expression (DGE) analyses were performed to identify sample- and gene-wise similarities between classifications, as well as develop and validate a new pCAFassigner gene signature. For prognostic impact, a published single sample classifier was used to identify a dominant CAF subtype in 1071 whole tumor samples, for which clinical information was available for 618 samples. The overall survival (OS) analysis was performed using Kaplan-Meier survival analysis.

Results As expected, our analysis revealed the synonymity between subtype-A and myCAF (91 %), subtypes-B and -C with iCAF (69 %) and subtype D with apCAF (91 %, FDR &lt; 0.001). We revised our pCAFassigner gene signature from a prediction analysis of microarrays (PAM) centroid to an 82 gene signature unique to each subtype. Given the similarities between these separate classifications, we sought to identify association of iCAF (subtype-B/C), apCAF (subtype-D) and myCAF (subtype-A) with survival. We observed a significant difference in OS with apCAF- and myCAF-dominant samples having the poorest prognosis, while patients with dominant iCAF had prolonged survival, questioning the understanding of iCAFs being pro-tumorigenic given its secretory nature and consequently, its presumed association with poor survival.

Conclusions Our results indicate that while methodologies to derive each CAF classification is distinct, ultimately, they have proven to be similar. Further, we reveal prognostic impact of iCAFs, apCAFs and myCAFs, supporting the use of these CAF subtypes as independent prognostic indicators for resected PDAC and will aid better management of the disease.

Citation Format: Aasia Hussain, Jiahui Ji, Prashant K. Srivastava, Anguraj Sadanandam. A comprehensive single cell analysis of cancer-associated fibroblasts (CAFs) reveals subtypes with prognostic impact in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 669.

[Heat stress induces neuronal apoptosis by up-regulating endoplasmic reticulum stress pathway]

OBJECTIVE

To explore the role of endoplasmic reticulum stress in heat stress-induced apoptosis of human neuroblastoma SH-SY5Y cells.

OBJECTIVE

SH-SY5Y cells were incubated at 43 ℃ for 2 h followed by further culture at 37 ℃ for 0, 3 h, or 6 h. With the cells cultured at 37 ℃ as the control, the cells exposed to heat stress were examined for morphological changes under optical microscope and changes in cell viability using CCK-8 assay. Flow cytometry was performed for detecting apoptosis of the cells following heat stress, and intracellular Ca²⁺ level in the cells was determined using flow cytometry and immunofluorescence confocal microscopy. The mRNA expression levels of caspase-12, BIP and XBP-1 in the cells were detected using qRT-PCR, and the protein expressions of caspase-12, BIP, P-JNK, JNK and XBP-1 were examined using Western blotting. The effect of pretreatment with 4-PBA on cell apoptosis following heat stress was analyzed with Western blotting.

OBJECTIVE

SH-SY5Y cells showed obvious cell shrinkage immediately after the exposure to heat stress, followed then by gradual cell stretching over time. The cell viability decreased significantly after heat stress (P=0.001), and the intracellular Ca²⁺ level increased significantly at 0 h and gradually recovered the normal level at 3 and 6 h. Heat stress induced significant increase in the protein expression of cleaved caspase-3 and time-dependent increase of caspase-12 (P=0.002) and BIP (P=0.008) expression at both the protein and mRNA levels. The expression of P-JNK/JNK protein increased significantly at 0 h (P=0.003) followed by gradual decrease; the expression levels of XBP-1 protein and mRNA gradually decreased after heat stress (P=0.005, P=0.002). Pretreatment with 4-PBA significantly reduced the expression level of cleaved caspase-3 in SH-SY5Y cells following heat stress.

OBJECTIVE

Heat stress induces apoptosis of SH-SY5Y cells by triggering endoplasmic reticulum stress and the imbalance of intracellular calcium ion homeostasis.

POS0788 CIRCULATING EXOSOMES PROMOTE LUPUS NEPHRITIS IN MRL-LPR MICE

Background:

Systemic Lupus Erythematosus (SLE) is a prototypic autoimmune disease that characterized by the loss of self-tolerance and the production of autoantibodies (autoAbs) [1, 2]. Lupus nephritis (LN), the severe organ-threatening manifestations of SLE, could cause massive damage to patients[3, 4]. Currently, some exosomal microRNAs (miRNAs) are considered as potential biomarkers in SLE. However, the role of exosomal miRNAs in Lupus Nephritis (LN) remains unclear.

Objectives:

The purpose of this study was to investigate molecular mechanism of plasma exosomal miRNAs in the development of Lupus Nephritis.

Methods:

Circulating exosomes were isolated from plasma of patients with LN, SLE without LN (NLN). Plasma exosomes were authenticated by Western Blot, Nanosight Tracking Analysis (NTA) and transmission electron microscopy (TEM). Fluorescence microscopy of co-cultured plasma exosomes and podocytes demonstrated that exosomes were uptaken into podocytes. Moreover, cell apoptosis and the inflammation factors was assessed using Western Blot. We analyzed the expression profiles of miRNAs in LN and NLN exosomes and the expression profiles of mRNAs of podocytes stimulated with LN and NLN exosomes with the help of next generation sequencing (NGS).

Results:

We demonstrate that exosomes derived from LN plasma could be taken by neighboring podocytes and promote the apoptosis of podocytes and the expression of inflammation factors. In addition, the sequencing found that miRNAs were differentially expressed in LN and NLN exosomes and mRNAs were differentially expressed in podocytes stimulated with LN and NLN exosomes.

Conclusion:

LN plasma exosomes have a potency to stimulate the apoptosis of podocytes and the expression of inflammation factors. Moreover, differentially expressed miRNAs in exosomes play a potential role in the development of LN.

References:

[1]T. Colasanti, A. Maselli, F. Conti, M. Sanchez, C. Alessandri, C. Barbati, D. Vacirca, A. Tinari, F. Chiarotti, A. Giovannetti, F. Franconi, G. Valesini, W. Malorni, M. Pierdominici, E. Ortona, Autoantibodies to estrogen receptor α interfere with T lymphocyte homeostasis and are associated with disease activity in systemic lupus erythematosus, Arthritis and rheumatism, 64 (2012) 778-787.

[2]H.A. Al-Shobaili, A.A. Al Robaee, A.A. Alzolibani, Z. Rasheed, Antibodies against 4-hydroxy-2-nonenal modified epitopes recognized chromatin and its oxidized forms: role of chromatin, oxidized forms of chromatin and 4-hydroxy-2-nonenal modified epitopes in the etiopathogenesis of SLE, Disease markers, 33 (2012) 19-34.

[3]A. Kaul, C. Gordon, M.K. Crow, Z. Touma, M.B. Urowitz, R. van Vollenhoven, G. Ruiz-Irastorza, G. Hughes, Systemic lupus erythematosus, Nat Rev Dis Primers, 2 (2016) 16039.

[4]M.G. Tektonidou, A. Dasgupta, M.M. Ward, Risk of End-Stage Renal Disease in Patients With Lupus Nephritis, 1971-2015: A Systematic Review and Bayesian Meta-Analysis, Arthritis & rheumatology (Hoboken, N.J.), 68 (2016) 1432-1441.

Disclosure of Interests:

None declared

OP0073 SINGLE-CELL TRANSCRIPTOMICS UNCOVERS DEFECTIVE BONE MARROW EARLY B CELL DEVELOPMENT IN A SUBSET OF LUPUS PATIENTS ASSOCIATED WITH AGGRAVATED INFLAMMATION

Background:

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that occurs when the body’s immune system attacks own tissues and organs. B cells play a central role in SLE pathogenesis by producing autoantibodies as well as antibody-independent functions. Peripheral B cell abnormality is well known in lupus patients such as expansions of plasmablasts and atypical memory B cells, which are associated with active diseases. However, little is known about the B cell development in the bone marrow of lupus patients.

Objectives:

We conduct this survey to explore the disorder of the B cell development in the bone marrow of lupus patients.

Methods:

In this study, we have performed the scRNASeq to profile the bone marrow B cell compartment in lupus patients and healthy donors.

Results:

We identified that in a subset of lupus patients, the early B cells (proB and preB cells) were strongly decreased, which were confirmed by flow cytometry in an expanded cohort. Furthermore, bone marrow B cells from these patients showed a strong proinflammatory signature revealed by pathway analysis. Interestingly, BCR repertoire analysis showed that the IGHV-4-34 was highly enriched in these patients, indicating an enhanced B cell tolerance defect. Finally, a panel of proinflammatory cytokines (TNF-a, IL-1a, IL-12p70, IFN-g, et al.) were strongly increased in the bone marrow plasma of these patients compared with early B normal patients and healthy donors, confirming a localized proinflammatory microenvironment.

Conclusion:

Altogether, the current study has revealed that a defective early B cell development in lupus patients is associated with a more severe B cell tolerance defect and aggravated inflammation, which may shed new light on developing novel therapies by targeting relevant pathways.

References:

[1]Min Wang, Hua Chen, Jia Qiu, et al. Antagonizing miR-7 suppresses B cell hyperresponsiveness and inhibits lupus development. J Autoimmun 2020.

[2]A M Jacobi, D M Goldenberg, F Hiepe, et al. Differential effects of epratuzumab on peripheral blood B cells of patients with systemic lupus erythematosus versus normal controls. Ann Rheum Dis, 2008.

Acknowledgements:

This work was funded by Special project of clinical medicine of Nantong University (Grant/Award number: 2019LQ001), National Natural Science Foundation of China (Grant/Award number: 81671616, 81871278 and 82071838).

Disclosure of Interests:

None declared

POS0787 BERBERINE MODULATE LUPUS SYNDROME VIA THE REGULATION OF GUT MICROBIOTA IN MRL/LPR MICE

Background:

Intestinal flora disorder and immune abnormalities have been reported in systemic lupus erythematosus (SLE) patients1,2. Berberine (BBR) showed significant effects in regulating the intestinal flora, repairing gut barriers and regulating immune cells3,4. While few reports mentioned the abnormal gut microbiota and metabolites in Chinese SLE patients.

Objectives:

Our investigation tried to illustrate the relationship between gut microbiota, intestinal metabolites and disease activity in Chinese SLE patients. And the effect of BBR to intestinal dysbacteriosis, multiple organ damages and over-activated immune system in MRL/Lpr mice.

Methods:

16S high-throughput (16S rRNA) sequence, qRT-PCR and gas chromatography technology were used to determine the gut microbiota and metabolites in 104 SLE patients from Affiliated Hospital of Nantong University, China. BBR was orally treated to the MRL/Lpr mice in low, medium and high doses. After 6 weeks treatment, mice were sacrificed. Serum, faeces and organs were collected for further studies.

Results:

Chinese SLE patients showed higher abundance of Bacteroidetes and lower abundance of Firmcutes. The results of qRT-PCR showed high Firmcutes/Bacteroidetes (F/B) ratio of SLE patients. The F/B ratio was negative correlated with SLE disease activity index (SLEDA) score. Almost all the tested short-chain fatty acids (SCFAs) found statistically significant results in SLE and LN (lupus nephritis) patients, especially the propanoic acid and butyric. BBR altered the relative abundance of Bacteroides and Verrucomicrobia and the butyric acid content in colon of MRL/Lpr mice. The increase of tight junction protein also indicated the gut barrier was repaired by BBR. Treg and Tfr cells in spleen and mesenteric lymph node (MLN) were increased. These results revealed a positive therapeutic effect of berberine on SLE from gut microbiota to immune status.

Conclusion:

Our study highlights current status of intestinal dysbacteriosis in Chinese patients with SLE and differences in intestinal metabolites among patients with different disease states. The regulation of intestinal flora and the repairment of gut barrier by intestinal metabolites in BBR treated mice seemed to be the factor that directed the immune responses and disease outcomes. The ultimate goal of our study was to determine the beneficial effects of regulating the gut microbiota on the treatment of SLE. The application of berberine is a relatively safe and convenient way. In the coming investigations, we plan to focus on the study of berberine and its metabolites on intestinal function and systemic immunity.

References:

[1]Guo, M. et al. Alteration in gut microbiota is associated with dysregulation of cytokines and glucocorticoid therapy in systemic lupus erythematosus. Gut microbes11, 1758-1773, doi:10.1080/19490976.2020.1768644 (2020).

[2]Mu, Q. et al. Control of lupus nephritis by changes of gut microbiota. Microbiome5, 73, doi:10.1186/s40168-017-0300-8 (2017).

[3]Habtemariam, S. Berberine pharmacology and the gut microbiota: A hidden therapeutic link. Pharmacological research155, 104722, doi:10.1016/j.phrs.2020.104722 (2020).

[4]Cui, H. et al. Berberine Regulates Treg/Th17 Balance to Treat Ulcerative Colitis Through Modulating the Gut Microbiota in the Colon. Frontiers in pharmacology9, 571, doi:10.3389/fphar.2018.00571 (2018).

Figure 1.

Disclosure of Interests:

None declared

POS0761 INVESTIGATION ON THE EFFECT AND MECHANISM OF ABNORMALLY ACTIVATED CD8+ T CELLS FROM BONE MARROW ON HEMATOPOIETIC STEM CELLS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

SLE is an autoimmune disease characterized by the abnormal function of lymphocytes. The impairment of hematopoietic function of bone marrow participates in its pathogenesis, in which T cells play an important role. However, study on bone marrow T cells in SLE patients is very limited.

Objectives:

This study aims to characterize the phenotype and molecular characteristics of abnormally activated CD8+T cells in bone marrow of SLE patients and explore the mechanism of hematopoietic stem cells (HSCs) reduction caused by the abnormally activated CD8+T cells in bone marrow of patients with SLE.

Methods:

A total of 8 SLE patients and 5 age- and sex-matched controls were recruited in our study. Among them, 3 SLE patients and 4 donors were collected bone marrow and peripheral blood samples for Single-cell RNA sequencing (scRNA-seq) and functional studies. BM and peripheral T cell subsets were measured by flow cytometry. Plasma cytokines and secreted immunoglobulins were detected by Luminex. Disease activity of SLE patients was measured using the SLE Disease Activity Index (SLEDAI). All analyses were performed using R language and Flowjo 9.

Results:

In the present study, SLE patients had increased CD8+T%αβT cells and decreased CD4+T%αβT cells in bone marrow of SLE, compared to healthy controls. A large number of CD38+HLADR+CD8+T cells existed in the bone marrow and peripheral blood of SLE patients. Those patients also showed reduced number of HSCs, and with a downward trend of the numbers of peripheral red blood cells, white blood cells, neutrophils, hemoglobin, and platelets. By scRNA-seq, the CD38+HLADR+CD8+T cells contained high levels of GZMK, GZMA, PRF1, IFNG, and TNF in the bone marrow of SLE patients. the CD38+HLADR+CD8+T cells exhibited significant relationship with HSCs, white blood cells, neutrophils, and platelets.

Conclusion:

These findings demonstrated that the abnormally activated CD8+T cells in bone marrow can reduce the number of HSCs by the expression of killer molecules, which contributes to the impairment of hematopoietic function and the development of SLE. This project focuses on the specific bone marrow T cell subset in SLE. The completement of this project provides information for exploring the mechanism of hematopoiesis involvement.

References:

[1]Anderson E, Shah B, Davidson A, Furie R. Lessons learned from bone marrow failure in systemic lupus erythematosus: Case reports and review of the literature. Semin Arthritis Rheum. 2018;48(1):90-104.

[2]Sun LY, Zhou KX, Feng XB, Zhang HY, Ding XQ, Jin O, Lu LW, Lau CS, Hou YY, Fan LM. Abnormal surface markers expression on bone marrow CD34+cells and correlation with disease activity in patients with systemic lupus erythematosus. Clin Rheumatol. 2007;26(12):2073-2079.

Acknowledgements:

We want to thank Lu Meng, Teng Li, Wei Zhou, and Jiaxin Guo for their assistance with this study.

Disclosure of Interests:

None declared

AB0066 MECHANISMS OF TOTAL SAPONINS OF PANAX JAPONICUS MITIGATES COLLAGEN-INDUCED ARTHRITIS

Background:

Total saponins of Panax japonicus (TSPJ) are extracted from Panax japonicus (T.Nees) C.A.Mey and have achieved a good therapeutic effect in the treatment of rheumatoid arthritis (RA). Unfortunately, the mechanism of TSPJ acting on RA is not clear.

Objectives:

To investigate the potential mechanisms and key targets of TSPJ on RA.

Methods:

The raw data were downloaded from the Gene Expression Omnibus (GEO) database, and the RStudio3.6.1 software was used to identify differentially expressed genes (DEGs). The potential targets of active compounds from TSPJ were predicted by the Pharmmapper and SwissTargetPrediction databases. Based on the overlapping genes, we used Cytoscape 3.7.2 software to construct a protein-protein interactions (PPI) network and to determine the mechanisms of the treatment by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Collagen-induced arthritis (CIA) model was established and treated with different doses of TSPJ. Arthritis index (AI) and histology score were used to evaluate the symptoms of CIA. The levels of vascular endothelial growth factor (VEGF), hypoxia-inducible factor 1 (HIF-1), IL-1β, and IL-17A tested by enzyme linked immunosorbent assay and real time-quantitative Polymerase Chain Reaction.

Results:

A total of 2670 DEGs and 371 TSPJ targets were obtained, including 52 overlapping genes. 41 genes had protein interactions that are used to build the PPI network. The results of the KEGG enrichment analysis included VEGF and HIF-1 signaling pathway. Seven negative correlation genes and 16 positive correlation genes were obtained by correlational analysis of DEGs in VEGF and HIF-1 signaling pathway. SRC proto-oncogene, nonreceptor tyrosine kinase (SRC), and the signal transducer and the activator of transcription 3 (STAT 3) had a higher value of degree in PPI and showed a significant correlation in the pathways; they were regarded as key targets. Compared with the CIA model group, TSPJ significantly decreased the AI and histology scores. Moreover, the expression of VEGF-A, HIF-1α, IL-1β, and IL-17A in serum or spleens significantly reduced in a dose-dependent.

Conclusion:

Present study show that SRC and STAT 3 may be the key targets of TSPJ acting on the VEGF and HIF-1 signaling pathways, thus inhibiting angiogenesis and improving RA.

Disclosure of Interests:

None declared

POS0785 CHANGING EXPRESSION PROFILES OF LONG NONCODING RNAS, MIRNAS, MRNAS AND CIRCULAR RNAS IN LABIAL SALIVARY GLANDS OF PRIMARY SJÖGREN’S SYNDROME (PSS)

Background:

Primary Sjögren’s syndrome (pSS) is a relatively common autoimmune disease characterized by oral and ocular dryness. An increasing number of studies have revealed that long non-coding RNA (lncRNA), miRNA, mRNA and circular RNA (circRNA) contributes to the pathogenesis of autoimmune diseases.

Objectives:

To explore lncRNA, miRNA, mRNA and circRNA expression profiles in labial salivary glands (LSGs) in pSS patients and their biological functions in the regulation of pSS.

Methods:

The expression of 75,550 lncRNAs, 2,318 miRNA, 20,292 mRNAs and 6,877 circRNAs were determined in the LSG of six pSS patients and six healthy controls using microarray experiments. Validation was performed in pSS patients and controls using real-time PCR. LncRNA-mRNA co-expression and gene-pathway networks were constructed using bioinformatics software.

Results:

A total of 599 lncRNAs (upregulated: 279, downregulated: 320), 78 miRNAs (upregulated: 26, downregulated: 52), 615 mRNAs (upregulated: 590, downregulated: 25) and 160 mRNAs (upregulated: 110, downregulated: 50) were differentially expressed in the LSGs of pSS patients. Five of these lncRNAs were validated using real-time PCR. lncRNA HCP5, lncRNA SNHG5, lncRNA IFI44L, lncRNA CMPK2 were significantly upregulated and lncRNA TTYH1 were downregulated in pSS. GO and KEGG biological pathway analysis were performed to predict the functions of differentially expressed lncRNAs and co-expressed potential targeting genes. Subsequently, a ceRNA (lncRNA-miRNA-mRNA) network including 2320 ceRNA pairs was constructed based on predicted miRNAs shared by lncRNAs and mRNAs.

Conclusion:

The expression profile provided a systematic perspective on the potential functions of lncRNAs miRNAs, mRNAs and circRNAs in the pathogenesis of pSS. Therefore, this study will aid in the development of new diagnostic biomarkers and drug therapies.

References:

[1]Le Dantec C, Varin MM, Brooks WH, Pers JO, Youinou P, Renaudineau Y. Epigenetics and Sjogren’s syndrome.Curr Pharm Biotechnol. 2012 Aug;13(10):2046-53.

Disclosure of Interests:

None declared

Genome-Wide Identification of Sequence Variations and SSR Marker Development in the Munake Grape Cultivar

The Munake grape cultivar produces uniquely flavored and high-quality fruits. Despite the numerous beneficial agronomic traits of Munake, there are few genetic resources available for this cultivar. To address this knowledge gap, the entire genome was sequenced using whole-genome sequencing approaches and compared with a Vitis vinifera L. reference genome. This study describes more than 3 million single nucleotide polymorphism (SNP), 300,000 insertion and deletion (InDel), 14,000 structural variation (SV), and 80,000 simple sequence repeat (SSR) markers (one SSR per 4.23 kb), as well as their primers. Among the SSRs, 44 SSR primer pairs were randomly selected and validated by polymerase chain reaction (PCR), allowing discrimination between the different Munake cultivar genotypes. The genetic data provided allow a deeper understanding of Munake cultivar genomic sequence and contribute to better knowledge of the genetic basis behind its key agronomic traits.

CARD8 polymorphism rs2043211 protects against noise-induced hearing loss by causing the dysfunction of CARD8 protein

Inflammation is a complicated process and is considered to be responsible for the development of noise-induced hearing loss (NIHL). CARD8 is an important component of inflammasome that has been implicated in inflammation. To decide the relationship between the polymorphisms of CARD8 gene and NIHL risk and deduce the potential mechanism, three SNPs (rs2043211, rs1062808, and rs12459322) were genotyped in a Chinese population consisting of 610 NIHL cases and 612 normal hearing controls. The possible impacts of SNPs on CARD8 structure and function were assessed using a variety of bioinformatics tools. Plasmids expressing wild-type and/or mutated CARD8 were transfected into HEK293 cells to verify the effect of SNPs on CARD8 protein expression level by western blot. The results revealed that rs2043211 AA genotype and A allele were associated with decreased risk of NIHL. Stratified analysis found that the male, drinking and exposed to noise ≥ 92 dB, subjects harboring rs2043211 A allele had a low risk of NIHL. The haplotype AGG (rs2043211-rs1062808-rs12459322) was significantly associated with a decreased risk of NIHL. SNP rs2043211 was predicted to be deleterious and affects CARD8 protein structure and stability. Furthermore, the functional experiment showed the mutant CARD8 could significantly decrease the CARD8 protein expression level. This study confirms that rs2043211 A allele may reduce NIHL risk by causing the loss of PPI combined with the decreased CARD8 expression level leading to CARD8 functional changes, and it may be one valuable genetic biomarker of NIHL susceptibility for Chinese noise-exposed workers.

Epigenetic differences in the innate response after immune stimulation during zebrafish sex differentiation

Infections are able to trigger epigenetic modifications; however, epigenetic-mediating infections in the immune system in fish is currently unavailable. Within this purpose, zebrafish were immune-stimulated with three lipopolysaccharides (LPS) during sex differentiation. Methylation patterns of three immune genes were studied by a candidate gene approach together with gene expression analysis, and in adulthood, sex ratios were determined. It was shown that the entrance of LPS was through the gills and accumulated in the pronephros. Significant hypomethylation levels of CASP9 and a significant CpG site for IL1β after Pseudomonas aeruginosa LPS exposure were found. No methylation difference was observed for TNFα. Gene expression and correlation data differed among studied genes. Sex ratios showed a feminization in dose and LPS strain-dependent manner. Here, it is provided epigenetic regulatory mechanisms derived by innate response and the first evidence of possible epigenetic interactions between the immune and reproductive systems.

Correction: Formononetin in Radix Hedysari extract-mediated green synthesis of gold nanoparticles for colorimetric detection of ferrous ions in tap water

Correction for ‘Formononetin in Radix Hedysari extract-mediated green synthesis of gold nanoparticles for colorimetric detection of ferrous ions in tap water’ by Xinyue Chen et al., RSC Adv., 2020, 10, 32897–32905, DOI: 10.1039/D0RA05660J.

The role of oxygen defects in metal oxides for CO2 reduction

The abuse of fossil fuels release large amount of CO2, causing intense global warming. Using photoreduction and electroreduction to convert CO2 into highly valuable fuels such as CO and CH4 can effectively solve this problem. However, due to the limited activity and selectivity, pristine catalyst materials cannot meet the requirements of practical applications, which means that some modifications to these catalysts are necessary. In this review, a series of research reports on oxygen defect engineering have been introduced. First, the methods of preparing oxygen defects by heat treatment, doping, and photoinduction combined with influencing factors in the preparation are introduced. Subsequently, common characterization methods of oxygen defects including EPR, Raman, XPS, EXAFS, and HRTEM are summarized. Finally, the mechanisms of introducing oxygen defects to improve CO2 reduction are discussed, and include enhancing light absorption, improving CO2 adsorption and activation, as well as promoting stability of the reaction intermediates. The summary of research on oxygen defects provides guidance for researchers who focus on CO2 reduction and accelerate the realization of its industrial applications in the future.

l-Carnitine protects against 1,4-benzoquinone-induced apoptosis and DNA damage by suppressing oxidative stress and promoting fatty acid oxidation in K562 cells

Widespread occupational and environmental exposure to benzene is unavoidable and poses a public health threat. Studies of potential interventions to prevent or relieve benzene toxicity are, thus, essential. Research has shown l-carnitine (LC) has beneficial effects against various pathological processes and diseases. LC possesses antioxidant activities and participates in fatty acid oxidation (FAO). In this study, we investigated whether 1,4-benzoquinone (1,4-BQ) affects LC levels and the FAO pathway, as well as analyzed the influence of LC on the cytotoxic effects of 1,4-BQ. We found that 1,4-BQ significantly decreased LC levels and downregulated Cpt1a, Cpt2, Crat, Hadha, Acaa2, and Acadvl mRNA expression in K562 cells. Subsequent assays confirmed that 1,4-BQ decreased cell viability and increased apoptosis and caspase-3, -8, and -9 activities. It also induced obvious oxidative stress and DNA damage, including an increase in the levels of reactive oxygen species and malondialdehyde, tail DNA%, and olive tail moment. Additionally, the mitochondrial membrane potential was significantly reduced. Cotreatment with LC (500 μmol/L) relieved these alterations by reducing oxidative stress and increasing the protein expression levels of Cpt1a and Hadha, particularly in the 20 μmol/L 1,4-BQ group. Thus, our results demonstrate that 1,4-BQ causes cytotoxicity, reduces LC levels, and downregulates the FAO genes. In contrast, LC exhibits protective effects against 1,4-BQ-induced apoptosis and DNA damage by decreasing oxidative stress and promoting the FAO pathway.