Reduction of Cu and nitrate leaching risk associated with EDDS-enhanced phytoextraction process by exogenous inoculation of plant growth promoting rhizobacteria

Biodegradable chelant (S,S)-N,N'-ethylenediaminedisuccinic acid (EDDS) has the more advantages of enhanced metal mobility, rapid degradation, environmental friendliness, and ammonium release. However, the risk of metal and/or nitrate residues and leaching within EDDS biodegradation remains as the bottleneck for the widespread application of EDDS-induced phytoremediation. This study aims to explore if the inoculation of plant growth-promoting rhizobacteria (PGPRs) can eliminate the risk associated with the short-term application of EDDS by investigating Cu phytoextraction and soil nitrate content. Results showed that EDDS application significantly increased the copper (Cu) concentration in shoots, soil total Cu, NH₄⁺-N and NO₃^--N content, but decreased plant biomass. The inoculation of PGPRs in the soil showed a strong ability to increase plant biomass, Cu phytoextraction and soil NH₄⁺-N content, and decrease soil Cu and NO₃^--N content. Moreover, bacterial dominant taxa were found to be the largest contributors to soil NH₄⁺-N and NO₃^--N variation, and the abundance of denitrifying bacteria (Bacteroidetes and Stenotrophomonas) decreased in the treatment with PGPRs. The risk of residual Cu and nitrate leaching was reduced by the inoculation of PGPRs without significantly changing the stability of the bacterial community. These new findings indicate that the exogenous application of beneficial rhizobacteria can provide an effective strategy to reduce the risk in metal-contaminated soils of chelant-assisted phytoextraction.

First-phase ejection fraction, a measure of pre-clinical heart failure, is strongly associated with increased mortality in patients with COVID-19

Introduction

Presence of heart failure is associated with a poor prognosis in patients with COVID-19. The aim of the present study was to examine whether first-phase ejection fraction (EF1), the ejection fraction measured in early systole up to the time of peak aortic velocity, a sensitive measure of pre-clinical heart failure, is associated with survival in patients hospitalised with COVID-19.

Methods

A retrospective outcome study was performed in patients hospitalised with COVID-19 who underwent echocardiography (n=380) at the West Branch of the Union Hospital, Wuhan, China and in patients admitted to King's Health Partners in South London UK. Association of EF1 with survival was performed using Cox proportional hazards regression. EF1 was compared in patients with COVID-19 and in historical controls with similar co-morbidities (n=266) who had undergone echocardiography before the COVID-19 pandemic.

Results

In patients with COVID-19, EF1 was a strong predictor of survival in each patient group (Wuhan and London). In the combined group, EF1 was a stronger predictor of survival than other clinical, laboratory and echocardiographic characteristics including age, co-morbidities and biochemical markers (figure 1). A cut-off value of 25% for EF1 gave a hazard ratio of 5.23 (95% CI: 2.85–9.60, p<0.001) unadjusted and 4.83 (95% CI: 2.35–9.95, p<0.001) when adjusted for demographics, co-morbidities, hs-cTnI and CRP (figure 2). EF1 was similar in patients with and without COVID-19 (23.2±7.3 vs 22.0±7.6%, p=0.092, adjusted for prevalence of risk factors and co-morbidities).

Conclusion

Impaired first-phase ejection fraction is strongly associated with mortality in COVID-19 and probably reflects pre-existing, pre-clinical heart failure.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Institute for Health Research (NIHR) UKBritish Heart Foundation (BHF) UK

Associated soil aggregate nutrients and controlling factors on aggregate stability in semiarid grassland under different grazing prohibition timeframes

Grazing prohibition is an effective measure in improving soil stability and ecological quality. However, only a limited number of studies have been published on the dominant factors that impact soil aggregate stability and their associated effects on nutrient distribution for different size soil aggregates under long-term grazing prohibition management. In this study, we investigated variation in soil aggregate stability and nutrient distribution characteristics in semiarid grassland sites under different grazing prohibition timeframes (0 years [GP0], 11 years [GP11], 26 years [GP26], and 36 years [GP36]). Results showed that organic carbon (C) and total nitrogen (TN) concentrations in soil aggregates decreased at GP11 before progressively increasing and reaching its highest value at GP36, and the total phosphorus (TP) concentration did not change significantly. Most nutrients accumulated in macroaggregates (> 0.25 mm) under grazing prohibition, and the nutrient stoichiometry in soil aggregates increased after 26 years. Compared to the control (GP0), the mean weight diameter (MWD) value of the soil stability index increased at GP11 (21.7%) and decreased at GP26 (18.9%). Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) also showed that the proportion of stable organic C-related functional groups (i.e., alkene-C and aromatic-C) in macroaggregates were higher at GP11 and GP36 than at GP26. Furthermore, principal component analysis (PCA), partial least squares path modeling (PLS-PM), and the relative importance of regressors all showed that glomalin-related soil proteins (GRSP) and nutrients indirectly improved aggregate stability in semiarid grassland through their influence on the GRSP accumulation potential and nutrient stoichiometry. Generally, after 26 years grazing prohibition had a positive effect on soil aggregate stability and nutrient accumulation in the semiarid grassland sites investigated for this study. Results from this study provide a theoretical basis to select appropriate grazing prohibition timeframes under grassland management initiatives to optimize ecological quality measures in semiarid regions.

Improvement of alfalfa resistance against Cd stress through rhizobia and arbuscular mycorrhiza fungi co-inoculation in Cd-contaminated soil

Rhizobia and arbuscular mycorrhiza fungi (AMF) are important symbiotic microbes that are advantageous to plants growing in metal-contaminated soil. However, it remains unclear how inoculated microbes affect rhizosphere microbial communities or whether subsequent changes in rhizosphere microbiomes contribute to improving plant resistance under metal stress. This study investigated the effects of rhizobia and AMF inoculation on alfalfa resistance to Cd stress. The response of rhizosphere microbial communities to inoculation and its role in increasing alfalfa' ability to cope with stress were further analyzed using high-throughput sequencing of 16S and ITS rRNA genes. Results showed that single rhizobia or AMF inoculation significantly improved alfalfa resistance to Cd stress, while their co-inoculation resulted in the greatest overall improvement. Improved resistance was reflected by the significant mitigation of Cd-induced lipid peroxidation and reactive oxygen species (ROS) stress caused by increases in antioxidant enzyme activities along with co-inoculation. Furthermore, co-inoculation significantly altered the rhizosphere microbial community structure by decreasing fungal community diversity and increasing bacterial community diversity. Results of partial least squares path modeling (PLS-PM) and variation partitioning analysis (VPA) showed that the rhizosphere bacterial community predominated over the fungal community with respected to improvements in resistance to Cd stress under the co-inoculation treatments. This improvement was specifically seen in the enrichment of certain key bacterial taxa (including Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflexi) induced by the rhizobia and AMF co-inoculation, enhancing alfalfa' ability to uptake rhizosphere nutrients and reduce its release of photosynthetically-derived carbon (C) into soil. Our findings revealed that the co-inoculation of multiple symbiotic microbes can assist plants to effectively cope with Cd stress, providing a greater understanding of rhizosphere bacterial taxa in the microbe-induced phytomanagement.

[Comparative study ofmethylene blue tracer and double tracer containing nuclide in sentinel lymph node biopsy of breast cancer]

Objective: To compare the application effect of blue dye single tracer and blue dye combined with nuclide double tracer in sentinel lymph node biopsy (SLNB) of breast cancer surgery. Methods: A total of 92 breast cancer patients in Shandong Cancer Hospital and Institute from November 2017 to October 2019 underwent methyleneblue dye combined with (99)Tc(m) sulfur colloid nuclide double tracer in SLNB, while other 92 cases in Jining First People Hospital underwent blue dye single tracer. The number of SLN detection, detection rate, accuracy rate, sensitivity, and false negative rate of the two groups were compared. The impacts of age, menstruation, tumor location, tumor size, clinical stage, pathological type, and estrogen receptor (ER), progesterone receptor (PR), human epidermal receptor 2 (HER-2), molecular typing, dynamic enhanced magnetic resonance imaging (DCE-MRI)on the detection rate of SLN were analyzed. Results: The number of detection, detection rate, accuracy, sensitivity, and false negative rate of the blue dye single tracer group were 3.20±1.10, 90.22%, 93.48%, 95.24% and 4.76%, respectively; the double tracer group were 3.37±1.02, 92.39%, 95.65%, 95.65% and 4.35%, respectively, without significant difference (all P>0.05). In different age, menstrual condition, tumor location, clinical stage, pathological type, ER, PR, HER-2 expression and molecular typing, the detection rate of single tracer group and double tracer group had no significant difference (all P>0.05). However, in the tumor size of 2-5 cm and without DCE-MRI examination, the detection rate of single tracer group was significantly lower than that of double tracer group. Conclusion: The effect of blue dye single tracer in detecting SLN of breast cancer is equivalent to that of double tracer method, which is worthy of promotion and application in primary hospitals.

Nitrogen of EDDS enhanced removal of potentially toxic elements and attenuated their oxidative stress in a phytoextraction process

(S,S)-ethylenediaminedisuccinic acid (EDDS) has a strong capacity to mobilize potentially toxic elements (PTEs) in phytoextraction. It can release NH₄⁺-N via biodegradation, which can enhance N supply to soil thereafter promote plant growth and plant resistance to PTEs. However, the advanced feature of released N in the EDDS-enhanced phytoextraction remains unclear. In the current study, the effects of N supply released from EDDS on ryegrass phytoextraction and plant resistance to PTEs were investigated in detail by a comparison with urea. Our results supported that the addition of both EDDS and urea increased N concentration in soil solution, yet EDDS needed more time to release available N for plant uptake and transported more N from root to shoot. Additionally, EDDS significantly increased the concentration of all targeted PTEs, i.e. Cu, Zn, Cd, and Pb, in the soil solution, which results in higher levels of their occurrence in plant biomass compared with urea. By contrast, the supply of N slightly enhanced the ryegrass uptake of micro-nutrients, i.e. Cu and Zn, yet it caused negligible effects on nonessential elements, i.e. Cd and Pb. The mobilized PTEs by EDDS lead to elevated oxidative stress because higher levels of malondialdehyde and O₂^•- were observed. The supply of N attenuated oxidative stress caused by O₂^•- and H₂O₂, which was associated with enhanced activities of superoxide dismutase and peroxidase. Our results advanced the understanding of the exogenous N supply and metal resistance mechanisms in the EDDS-enhanced phytoextraction. This study also highlighted that EDDS can serve as a N source to ease N-deficient problems in PTEs-contaminated soils.

MicroRNA-495 attenuates proliferation and inflammatory response in rheumatoid arthritis fibroblast-like synoviocytes through attenuating β-catenin pathway

Fibroblast-like synoviocytes (FLSs) exert a critical effect in the occurrence and progress of rheumatoid arthritis (RA). MicroRNA-495 (miR-495) can regulate many growth behaviors in various cell types. Nevertheless, the role of miR-495 is still unclear in RA-FLS. We aimed to explore the role and molecular mechanism of miR-495 in RA. The FLSs and synovial tissue from normal and RA cases were used in the study. RT-PCR analysis was used to examine the expression of miR-495. Western blot assay was conducted to determine the levels of matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-2 (MMP-2) and β-catenin. Cell counting kit-8 (CCK-8) assays were performed to determine the proliferation of RA-FLS in different treatment groups. The results showed that miR-495 is down-regulated in both RA-synovial tissue and RA-FLSs. Overexpression of miR-495 could inhibit RA-FLS proliferation and inflammatory factors of interleukin (IL)-6, IL-11 and tumor necrosis factor alpha (TNF-α), and decrease the protein expression of MMP-9 and MMP-2. In addition, miR-495 could negatively regulate the expression of β-catenin in RA-FLSs. We also confirmed that the inhibitory role of miR-495 in RA-FLS is through the regulation of β-catenin expression. Taken together, miR-495 is downregulated in RA-FLS and RA synovial tissue, and miR-495 inhibits proliferation and inflammatory response in RA-FLS, partially via regulating β-catenin expression. The miR-495/β-catenin pathway may serve as a new therapeutic target for RA.

First-phase ejection fraction predicts response to cardiac resynchronization therapy and adverse outcomes

Background

Cardiac Resynchronization Therapy (CRT) is an important therapeutic treatment for chronic heart failure. However, even in carefully selected cases up to 40% of patient fail to respond. First-phase ejection fraction (EF1), the ejection fraction up to the time of maximal ventricular contraction, is a novel and more sensitive echocardiographic measure of early systolic function.

Purpose

We examined the value of EF1, to predict response to CRT and clinical outcomes after CRT.

Methods

We analysed echocardiograms from 197 patients who underwent CRT between 2009 and 2018 and were followed to determine clinical outcomes.

Results

Volumetric response rate (reduction in end-systolic volume ≥15%) was 92.3% vs. 12.1%, for those with EF1 in the highest vs. lowest tertiles (p&lt;0.001). A cut-off value of 11.9% for EF1 had &gt;85% sensitivity and specificity for prediction of response to CRT; on multivariate logistic regression analysis incorporating previously defined predictors, EF1 was the strongest predictor of response (OR: 1.563, 95% CI: 1.371–1.782, p&lt;0.001) (table 1). EF1 was also the strongest predictor of a clinical composite score (OR: 1.115, 95% CI: 1.044–1.191, p=0.001). Improvement in EF1 at 6 months after CRT implantation (6.5±5.8% vs 1.8±4.3% in responders vs. non-responders, p&lt;0.001) was the best predictor of heart failure re-hospitalization and death after median follow-up of 29.2 months (HR: 0.819, 95% CI:0.765–0.876, p&lt;0.001).

Conclusion

EF1 is a promising marker to identify patients likely to respond to CRT and most likely provides a measure of myocardial viability that determines response.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): British Heart Foundation, Wellcome/EPSRC Centre for Medical Engineering

A novel extracellular enzyme stoichiometry method to evaluate soil heavy metal contamination: Evidence derived from microbial metabolic limitation

Heavy metal contaminates have become a significant threat to soil ecosystems due to their chronicity and universality in soil. Soil microbial metabolism plays a vital role in biogeochemical cycles and soil functions. However, the response of microbial metabolism to heavy metal contamination in soil remains elusive despite potentially offering important insight into the health and ecological consequences of soil ecosystems under such contamination. This study used extracellular enzyme stoichiometry models to identify the response of microbial metabolism to various heavy metal contaminants, while also revealing potential implications of heavy metal contaminates in soil ecosystems. Results showed that microbial metabolism was restricted by soil carbon (C) and phosphorus (P) within a heavy metal polluted area in Northwest China. Heavy metal stress significantly increased microbial C limitation while decreasing microbial P limitation. However, microbial C and P limitations both responded consistently to different heavy metals (i.e., Cd, Pb, Zn, and Cu). Heavy metals had the greatest effect on microbial C limitation (i.e., 0.720 of the total effects) compared to other soil properties, and soil with the lowest heavy metal concentration exhibited the lowest microbial C limitation, and vice versa. These results indicated that microbial metabolic limitation can robustly and sensitively reflect the degree of heavy metals pollution in soil. Additionally, increased microbial C limitation caused by heavy metal contaminants could potentially escalate C release by promoting soil C decomposition as well as increasing investments in enzyme production and the maintenance of metabolic processes. Consequently, potential C loss induced by heavy metal pollution on soil ecosystems may be extensive and significant. Generally, our results suggest the usefulness of extracellular enzyme stoichiometry as a new method from which to evaluate heavy metal soil pollution, while microbial metabolic limitation could potentially be a promising indicator.

Exogenous application of signaling molecules to enhance the resistance of legume-rhizobium symbiosis in Pb/Cd-contaminated soils

Being signaling molecules, nitric oxide (NO) and hydrogen sulfide (H₂S) can mediate a wide range of physiological processes caused by plant metal toxicity. Moreover, legume-rhizobium symbiosis has gained increasing attention in mitigating heavy metal stress. However, systematic regulatory mechanisms used for the exogenous application of signaling molecules to alter the resistance of legume-rhizobium symbiosis under metal stress are currently unknown. In this study, we examined the exogenous effects of sodium nitroprusside (SNP) as an NO donor additive and sodium hydrosulfide (NaHS) as a H₂S donor additive on the phytotoxicity and soil quality of alfalfa (Medicago sativa)-rhizobium symbiosis in lead/cadmium (Pb/Cd)-contaminated soils. Results showed that rhizobia inoculation markedly promoted alfalfa growth by increasing chlorophyll content, fresh weight, and plant height and biomass. Compared to the inoculated rhizobia treatment alone, the addition of NO and H₂S significantly reduced the bioaccumulation of Pb and Cd in alfalfa-rhizobium symbiosis, respectively, thus avoiding the phytotoxicity caused by the excessive presence of metals. The addition of signaling molecules also alleviated metal-induced phytotoxicity by increasing antioxidant enzyme activity and inhibiting the level of lipid peroxidation and reactive oxygen species (ROS) in legume-rhizobium symbiosis. Also, signaling molecules improved soil nutrient cycling, increased soil enzyme activities, and promoted rhizosphere bacterial community diversity. Both partial least squares path modeling (PLS-PM) and variation partitioning analysis (VPA) identified that using signaling molecules can improve plant growth by regulating major controlling variables (i.e., soil enzymes, soil nutrients, and microbial diversity/plant oxidative damage) in legume-rhizobium symbiosis. This study offers integrated insight that confirms that the exogenous application of signaling molecules can enhance the resistance of legume-rhizobium symbiosis under metal toxicity by regulating the biochemical response of the plant-soil system, thereby minimizing potential health risks.

Co-inoculation effect of plant-growth-promoting rhizobacteria and rhizobium on EDDS assisted phytoremediation of Cu contaminated soils

Chelants application can increase the bioavailability of metals, subsequently limiting plant growth and reducing the efficiency of phytoremediation. Plant growth-promoting rhizobacteria (PGPRs) and rhizobium have substantial potential to improve plant growth and plant tolerance to metal stress. We evaluated the effects of co-inoculation with a PGPR strain (Paenibacillus mucilaginosus) and a Cu-resistant rhizobium strain (Sinorhizobium meliloti) on the efficiency of biodegradable chelant (S,S-ethylenediaminedisuccinic acid; EDDS) assisted phytoremediation of a Cu contaminated soil using alfalfa. The highest total Cu extraction by alfalfa was observed in the EDDS-treated soil upon co-inoculation with the PGPR and rhizobium strains, which was 1.2 times higher than that without co-inoculation. Partial least squares path modeling identified plant oxidative damage and soil microbial biomass as the key variables influencing Cu uptake by alfalfa roots. Co-inoculation significantly reduced the oxidative damage to alfalfa by mitigating the accumulation of malondialdehyde and reactive oxygen species, and improving the antioxidation capacity of the plant in the presence of EDDS. EDDS application decreased microbial diversity in the rhizosphere, whereas co-inoculation increased microbial biomass carbon and nitrogen, and microbial community diversity. Increased relative abundances of Actinobacteria and Bacillus and the presence of Firmicutes taxa as potential biomarkers demonstrated that co-inoculation increased soil nutrient content, and improved plant growth. Co-inoculation with PGPR and rhizobium can be useful for altering plant-soil biochemical responses during EDDS-enhanced phytoremediation to alleviate phytotoxicity of heavy metals and improve soil biochemical activities. This study provides an effective strategy for improving phytoremediation efficiency and soil quality during chelant assisted phytoremediation of metal-contaminated soils.

SAT0140 SAFETY OF TOFACITINIB THERAPY IN HBSAG CARRIERS WITH RHEUMATOID ARTHRITIS: A PROSPECTIVE STUDY

Background:

Targeted synthetic DMARDs (ts-DMARDs) are becoming more available and affordable in developing countries, where the prevalence of hepatitis B virus (HBV) infection is still an important public health issue. The safety of ts-DMARDs therapy in terms of the reactivation of hepatitis B virus (HBV) infection need more concern. Rare data from a prospective study focus on the use of ts-DMARDs in patients with concurrent rheumatoid arthritis (RA) and HBV infection were available by now.

Objectives:

To evaluate the influence of tofacitinib on reactivation of HBV infection in HBsAg carriers with RA.

Methods:

In this 52 weeks observation, HBsAg carriers with active RA (DAS28>5.1) despite failed combined treatment with MTX and other non-biological DMARDs were enrolled. Patients must have normal liver function prior to study. All patients received therapy with tofacitinib (5mg twice daily) and concomitant MTX (10-12.5mg/w). Entecavir was prescribed preventively for patients who had a baseline HBV load >2000 copy/ml (group 1), and Lamivudin for patients with HBV load ≤ 2000 copy/ml (group 2). Liver enzymes (AST/ALT) and HBV viral load were monitored every 4 weeks. Increased viral load and abnormal liver function were managed according to expert opinion.

Results:

Thirteen patients (10 female) were recruited. Nine patients had a baseline viral load >2000 copy/ml (group 1, with preventive Entecavir), and the other 4 patients had a viral load ≤ 2000 copy/ml (group 2, with preventive Lamivudin). Two patients from group 1 discontinued tofacitinib at week 12 due to ineffectiveness, and both continued taking Entecavir for another 3 months after the discontinuation of tofacitinib.

No reactivation of hepatitis B was observed in patients from group 1. One patients (female, 54 years old) from group 2 underwent a mild increase of both ALT and AST (67 and 56 IU/L, respectively) at week 16. An elevated viral load (4.9e6 copies/ml, baseline 1.4e3) and a HBV YMDD mutant was also found. The tofacitinib treatment continued. After prescription of Adefovir (combined with the pre-existing Lamivudin), both liver enzyme and viral load decreased to normal range in 8 weeks and remained normal throughout the study.

Conclusion:

An aggressive Tofacitinib + MTX therapy may be a safe option for HBsAg carriers with cs-DMARDs refractory RA. More active and effective prophylaxis strategy may be recommended to reduce the risk of HBV reactivation during the treatment.

References:

[1]Chen YM, Huang WN, Wu YD, et al. Reactivation of hepatitis B virus infection in patients with rheumatoid arthritis receiving tofacitinib: a real-world study. Ann Rheum Dis 2018; 77:780-2.

Disclosure of Interests: :

None declared

THU0385 SAFETY OF TOFACITINIB THERAPY IN HBSAG CARRIERS WITH ANKYLOSING SPONDYLITIS: A PROSPECTIVE STUDY

Background:

Targeted synthetic DMARDs (ts-DMARDs) are becoming more available and affordable in developing countries, where the prevalence of hepatitis B virus (HBV) infection is still an important public health issue. The safety of ts-DMARDs therapy in terms of the reactivation of hepatitis B virus (HBV) infection need more concern. Rare data from a prospective study focus on the use of ts-DMARDs in patients with concurrent ankylosing spondylitis (AS) and HBV infection were available by now.

Objectives:

To evaluate the influence of tofacitinib on reactivation of HBV infection in HBsAg carriers with AS.

Methods:

In this 52 weeks observation, HBsAg carriers with active AS (BASDAI ≥ 4) despite failed treatment with at least two NSAIDs and sulfasalazine (for patients with persistent peripheral arthritis) were studied. Patients must be positive for HBsAg and have a normal liver function prior to study.

All patients received therapy with tofacitinib (5mg twice daily). Entecavir were prescribed preventively regardless of individual viral load. Pre-existing NSAIDs and sulfasalazine were allowed. Liver enzymes (AST/ALT) and HBV viral load were monitored every 4 weeks. Increased viral load and abnormal liver function were managed according to expert opinion.

Results:

Eleven patients (9 male) were recruited. Eight patients had a baseline viral load >2000 copy/ml (group 1), and the other 3 patients had a viral load ≤ 2000 copy/ml (group 2). Two patients from group 1 discontinued tofacitinib at week 12 due to ineffectiveness, and both continued taking Entecavir for another 3 months after the discontinuation of tofacitinib.

One patients (male, 26 years old) from group 1 underwent a mild increase of both ALT and AST (67 and 56 IU/L, respectively) at week 16, but no elevated viral load (2.1e3 copies/ml, baseline 2.8e3) or a HBV YMDD mutant was found. The tofacitinib treatment continued. After prescription of polyene phosphatidyl choline, the liver enzyme of this patient decreased to normal range in 4 weeks and remained normal throughout the study.

No reactivation of hepatitis B was observed in patients from group 2.

Conclusion:

Tofacitinib treatment may be a safe and effective option for HBsAg carriers with AS refractory to traditional treatment. Prophylaxis strategy with effective anti-viral drugs is recommended.

References:

[1]Chen YM, Huang WN, Wu YD, et al. Reactivation of hepatitis B virus infection in patients with rheumatoid arthritis receiving tofacitinib: a real-world study. Ann Rheum Dis 2018; 77:780-2.

Disclosure of Interests:

None declared

The transcription factor VaNAC17 from grapevine (Vitis amurensis) enhances drought tolerance by modulating jasmonic acid biosynthesis in transgenic Arabidopsis

Expression of VaNAC17 improved drought tolerance in transgenic Arabidopsis by upregulating stress-responsive genes, modulating JA biosynthesis, and enhancing ROS scavenging. Water deficit severely affects the growth and development of plants such as grapevine (Vitis spp.). Members of the NAC (NAM, ATAF1/2, and CUC2) transcription factor (TF) family participate in drought-stress-induced signal transduction in plants, but little is known about the roles of NAC genes in drought tolerance in grapevine. Here, we explored the role of VaNAC17 in Vitis amurensis, a cold-hardy, drought-tolerant species of grapevine. VaNAC17 was strongly induced in grapevine by drought, exogenous abscisic acid (ABA), and methyl jasmonate (MeJA). A transient expression assay in yeast indicated that VaNAC17 functions as a transcriptional activator. Notably, heterologous expression of VaNAC17 in Arabidopsis thaliana enhanced drought tolerance. VaNAC17-expressing Arabidopsis plants showed decreased reactive oxygen species (ROS) accumulation compared to wild-type plants under drought conditions. RNA-seq analysis indicated that VaNAC17 expression increased the transcription of downstream stress-responsive genes after 5 days of drought treatment, especially genes involved in jasmonic acid (JA) biosynthesis (such as LOX3, AOC1 and OPR3) and signaling (such as MYC2, JAZ1, VSP1 and CORI3) pathways. Endogenous JA levels increased in VaNAC17-OE plants under drought stress. Taken together, these results indicate that VaNAC17 plays a positive role in drought tolerance by modulating endogenous JA biosynthesis and ROS scavenging.

[Evaluation on the effect of comprehensive intervention combined with clinical preventive services and lifestyle adjustment among high-risk populations of cardiovascular disease in Tongxiang City]

Objective: To evaluate the effect of comprehensive intervention combined with clinical preventive services and lifestyle adjustment on high-risk populations of cardiovascular disease. Methods: In 2015, 4 towns (streets) in Tongxiang City, of Zhejiang Province including Heshan Town, Longxiang Street, Wutong Street, and Fengming Street, were selected by using the typical sampling. The towns (streets) were allocated to the intervention group (Heshan Town and Longxiang Street) and the control group (Wutong Street and Fengming Street) by using the cluster random sampling. In each town (street), hypertension patients aged 50 to 74 years old who were taking community medicine management and with a 10-year cardiovascular disease risk ≥10% were recruited as subjects. There were 1 823 subjects in the intervention group and 1 883 in the control group. The intervention group was given a 1-year comprehensive intervention combining clinical preventive services and lifestyle adjustment, while the control group received routine chronic disease management. After the intervention, the final questionnaire investigation was conducted and health physical examination data were obtained. The death, acute coronary heart disease events and stroke incidence were the primary outcomes, and cardiovascular disease-related knowledge and behavior, clinical preventive services utilization, physical changes, blood fat index and 10-year cardiovascular disease risk were the secondary outcomes. The difference-in-difference model was used to evaluate the effects of interventions. Results: The age of subjects in the intervention and control group was (68.76±3.75) and (67.90±4.56) years old, respectively. After 1-year intervention, the incidence of mortality, acute coronary events and stroke in intervention group was 1.65% (30 cases), 0.27% (5 cases) and 2.69% (49 cases), respectively, which showed no statistical difference compared to the control group [1.33% (25 cases), 0.32% (6 cases) and 2.07% (39 cases)]. After adjusting for the age, gender, education, marital status, self-assessed family income level and situation of taking antihypertensive drugs, the difference-in-difference model showed that the body mass index and diastolic blood pressure in the intervention group decreased by 0.33 kg/m(2) and 1.49 mmHg (1 mmHg=0.133 kPa). Compared with the control group, daily vegetable consumption proportion, the awareness rates of aspirin, stains, salt intake, and oil intake increased by 4.76%, 26.22%, 29.56%, 10.80%, and 15.17%, respectively (P<0.05). Conclusion: After the 1-year comprehensive intervention, there was no significant change in primary outcomes among high-risk populations of cardiovascular disease. In secondary outcomes, body mass index and diastolic blood pressure declined and cardiovascular disease-related knowledge awareness increased.

Molecular Mechanisms of Lead Binding to Ferrihydrite-Bacteria Composites: ITC, XAFS, and μ-XRF Investigations

Binding of Pb(II) to ferrihydrite-Bacillus subtilis composites formed in the presence of bacterial cells were investigated through macroscopic and microscopic techniques. Diffuse layer model (DLM) fitting and isothermal titration calorimetry (ITC) analysis indicated that the hydroxyl group played a key role in Pb(II) sorption onto composites by masking reactive sites, such as carboxyl and phosphoryl groups of bacterial cells. Negative enthalpy (from -39.29 to -57.87 kJ mol^-1) and positive entropy (from 135.61 to 193.47 kJ mol^-1) of Pb(II) sorption onto composites revealed that inner-sphere complexes formed through exothermic reactions and was driven by both entropy and enthalpy. Spatial distribution of these inner-sphere species at varied Pb(II) loading demonstrated that interactions between Pb(II) and bacterial cells preceded that of mineral components in composites, using microfocus X-ray fluorescence spectroscopy (μ-XRF) maps and microfocus X-ray absorption near edge structure (μ-XANES) spectra. Combined with bulk Pb L_III-edge X-ray absorption fine structure (XAFS) spectrum, we inferred that mononuclear bidentate edge-sharing hydroxyl-Pb complexes, monodentate mononuclear carboxyl-Pb and phosphoryl-Pb complexes predominantly contributed to Pb(II) inner-sphere binding with mineral and bacterial fractions in composites, respectively. The molecular binding mechanisms obtained in this study provide further insight into the sequestration and migration of toxic metals in natural environments.

[Feasibility evaluation of estimating the 24-hour urinary sodium excretion in Chinese population with three spot urine methods]

Objective: To evaluate the feasibility of three spot urine methods (Kawasaki, INTERSALT and Tanaka) for estimating the 24 h urinary sodium excretion in the Chinese population. Methods: In 2017, 1 499 participants aged 18 to 69 years old were selected from Yiwu City, Haining City, Taishun County, Yinzhou District of Ningbo City and Liandu District of Lishui City of Zhejiang Province by using the multistage random sampling method. Sociodemographic information of the subjects was collected with questionnaires and physical measurements were performed. 24 h urine was collected and urinary volume was recorded. The concentrations of urinary sodium, potassium and creatinine were also measured. Kawasaki, INTERSALT and Tanaka spot urine methods were applied to estimate the 24 h urinary sodium excretion and compared with actual values among 1 426 participants who passed urine integrity test. Results: The age of participants was (46.71±14.04) years old, including 700 males, accounting for 49.1%. The actual value of 24 h urinary sodium excretion was (167.10±74.70) mmol, but Kawasaki method overestimated it as (184.61±57.10) mmol, and INTERSALT and Tanaka methods underestimated it as(134.62±39.21) and (143.20±35.66) mmol. Estimated difference (95%CI) (mmol) from small to large was Kawasaki method [17.51 (13.54, 21.47)], Tanaka method [-23.90 (-27.60, -20.20)] and INTERSALT method [-32.48 (-36.29, -28.67)]. With the increase of 24 h sodium intake, all estimation methods changed from the overestimation to underestimation. In those with 24 h sodium intake <9.0 g, the estimated difference (95%CI) of the INTERSALT method was the smallest as 43.15 (37.73, 48.57) and 1.26 (-2.10, 4.63) mmol for <6.0 and 6.0-8.9 g groups, respectively. In those with 24 h sodium intake≥9.0 g, the Kawasaki method had the smallest estimated difference (95%CI) as -12.50 (-18.14, -6.86) and -53.73 (-61.25, -46.22) for 9.0-11.9 g and ≥ 12.0 g group, respectively. The consistency analysis of the Bland-Altman method showed that the Kawasaki method had the best consistency with actual measured value and it had the least number of points outside the range (69 points accounting for 4.84%). Conclusion: Among the three spot urine methods, the Kawasaki method has better applicability in predicting the excretion of 24 h urine sodium in the Chinese population.

[Analysis of magnetic resonance imaging characteristics in Chinese patients with myelin oligodendrocyte glycoprotein antibody associated disorders]

Objective: To investigate the magnetic resonance imaging (MRI) characteristics in the brain and spinal cord of Chinese patients with myelin oligodendrocyte glycoprotein antibodies associated diseases (MOGAD). Methods: Forty nine MOGAD patients with seropositive MOG-IgG and 58 AQP4-IgG positive patients were enrolled in this study. The characteristics of brain and spinal cord MRI were retrospectively analyzed. Results: There was no significant difference in the proportion of abnormal brain MRI of the two groups (69.4% vs 65.5%, P=0.177) , while the proportion of abnormal spinal cord MRI of the AQP4-IgG positive group was significantly higher than that in the MOG-IgG positive group (84.5% vs 36.7%, P=0.001) . The proportion of MOG-IgG positive patients with subcortical white matter lesions and large lesions in the brain MRI was significantly higher than that in AQP4-IgG positive group (48.9% vs 13.8%, P=0.003, 46.9% vs 12.1%, P=0.000) . The longitudinally extensive transverse myelitis in spinal cord MRI of AQP4-IgG positive group was significantly higher than that in the MOG-IgG group (70.7% vs 24.5%, P=0.002) . In addition, the proportion of MOG-IgG positive child patients with large lesions in the brain was significantly higher than that in AQP4-IgG positive child patients (76.9% vs 20.0%, P=0.047) . Conclusion: Demyelinating MRI lesions caused by MOG-IgG are heterogeneous, and could lead to a wide range of clinical phenotypes which is significantly different from those with AQP4-IgG.

Direct medical burden of antimicrobial-resistant healthcare-associated infections: empirical evidence from China

BACKGROUND

Antimicrobial resistance (AMR) and healthcare-associated infections (HAIs) are among the biggest global public health challenges, and overlap widely. These infections cause significant morbidity and mortality, put pressure on health systems, and incur rising direct and indirect costs.

AIM

This study analysed the direct medical burden attributable to AMR-HAIs in Chinese public tertiary hospitals, and aimed to inform both the medical regulators and hospital managers for better control of HAIs and containment of AMR.

METHODS

The propensity score matching method (γ= 0.25σ, nearest neighbor 1:1 matching) was applied to conduct a retrospective cohort study in five public tertiary hospitals in the Hubei province of China during 2013-2015. Descriptive analysis, Pearson's chi-squared test, Mann-Whitney U-test, Wilcoxon signed-rank test and paired/independent Z/T test were conducted. The statistically significant level was set at P<0.05.

FINDINGS

From 2013 to 2015 overall, the additional total medical expenditure per HAI-AMR inpatient was US$15,557.25 compared with that of the non-HAIs, and the additional length of per hospital stay of the HAI-AMR inpatient was 41 days compared with that of the non-HAIs (P<0.001).

CONCLUSIONS

In combination with AMR, HAIs caused significant additional medical expenses and affected the turnover rate of hospital beds. Most of the increased medical costs fell to patients and their families. These findings call for more effective control of HAIs and containment of AMR. A national study is needed to estimate the medical, social and economic burden of HAIs in combination with AMR.

Application of signaling molecules in reducing metal accumulation in alfalfa and alleviating metal-induced phytotoxicity in Pb/Cd-contaminated soil

The utilization of forages grown on metal-contaminated soil can increase the risk of heavy metals entering the food chain and affecting human health because of elevated toxic metal concentrations. Meanwhile, hydrogen sulfide (H₂S) and nitric oxide (NO) as signaling molecules are known to promote plant growth in metal-contaminated soils. However, the regulatory mechanisms of such molecules in plant physiology and soil biochemistry have not been well-documented. Hence, we investigate the role of the exogenous application of H₂S and NO on alfalfa growth in lead/cadmium (Pb/Cd)-contaminated soil. Our results indicate that the signaling molecules increase the alfalfa chlorophyll and biomass content and improve alfalfa growth. Further, H₂S and NO reduce the translocation and bioconcentration factors of Pb and Cd, potentially reducing the risk of heavy metals entering the food chain. These signaling molecules reduce metal-induced oxidative damage to alfalfa by mitigating reactive oxygen species accumulation and increasing antioxidant enzyme activities. Their exogenous application increases soil enzymatic activities, particularly of catalase and polyphenol oxidase, without significantly changing the composition and structure of rhizosphere bacterial communities. Interestingly, H₂S addition enriches the abundance of plant-growth-promoting rhizobacteria in soil, including Nocardioides, Rhizobium, and Glycomyces. H₂S is more effective than NO in improving alfalfa growth and reducing heavy-metal contamination of the food chain. These results provide new insights into the exogenous application of signaling molecules in alleviating metal-induced phytotoxicity, including an efficient strategy for the safe use of forages.

P5390Adipolin/C1q/Tnf-related protein 12 attenuates adverse cardiac remodeling in a mouse model of myocardial infarction

Background

Ischemic heart disease is one of leading causes of death worldwide. Obesity is closely linked to the development of cardiovascular diseases including ischemic heart disease. Adipose tissue produces various secretory bioactive proteins called as adipokines, and dysregulation of adipokine production contributes to the pathogenesis of obesity-related complications. Previously we identified adipolin, also referred to as C1q/Tnf-related protein12, as an insulin-sensitizing adipokine that is down-regulated in obesity. Here, we investigated the effects of adipolin on cardiac remodeling in a mouse model of myocardial infarction (MI).

Method

Male adipolin-knockout (APL-KO) and wild-type (WT) mice were subjected to the permanent ligation of the left anterior descending coronary artery to create MI. Echocardiographic and histological analyses were performed to evaluate cardiac function and myocardial remodeling at 4 weeks after MI. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Cardiomyocyte cross sectional area was evaluated by Wheat Germ Agglutinin staining. Perivascular fibrosis was assessed by Masson's trichrome staining. Neonatal rat ventricular myocytes were used as cultured cardiac myocytes for in vitro study.

Results

APL-KO mice exhibited increased ratios of the heart weight/body weight and lung weight/body weight after MI compared with WT mice. APL-KO mice showed increased left ventricular diastolic diameter and decreased fractional shortening after MI compared with WT mice. APL-KO mice had increases in myocardial apoptosis, cardiomyocyte hypertrophy and perivascular fibrosis at the remote zone of infarct hearts as compared with WT mice. Treatment of cultured cardiomyocytes with adipolin protein reduced apoptosis in response to 24 hours of hypoxia. Treatment with adipolin protein also increased the phosphorylation of Akt in cardiomyocytes. Inhibition of PI3 kinase/Akt signaling by LY294002 reversed the anti-apoptotic effects of adipolin in cultured cardiomyocytes.

Conclusion

Our data indicate that adipolin prevents pathological myocardial remodeling after chronic ischemia, at least in part, by suppressing myocardial apoptosis through an Akt-dependent mechanism.