Qualitative and quantitative analysis of glutathione and related impurities in pharmaceuticals by qNMR

In this study, an alternative method to compendial analytical procedures with enhanced detection and separation capabilities was validated for the quality assessment of glutathione (GSH) drug substance. The related impurities A, B, C, and D present in GSH drug substance were characterized using a one-dimension proton nuclear magnetic resonance (1D 1H NMR) method on a 600 MHz spectrometer equipped with a liquid nitrogen cryoprobe. Two sample preparations at different pH were optimized to ensure the unambiguous identification of different impurities in the GSH samples. Specifically, impurities A and C in a GSH sample can be tested at pH 3.0, while pH 7.4 is more suitable for testing impurities B and D. The quantitative NMR (qNMR) method was validated following International Council for Harmonisation (ICH) guidelines. The limit of detection (LOD) was less than 0.1% wt for an individual impurity, and the limit of quantitation (LOQ) ranged from 0.14 to 0.24% wt, using about 14 min experimental time per spectrum. Following validation, the qNMR method was applied to assess different commercial GSH bulk substance samples, an in-house compounded GSH drug product, and a GSH dietary supplement product. The method was also applied to monitor GSH degradation (hydrolysis and oxidation) over time to provide quantitative information on GSH degradation and stability. The results suggest that the qNMR method can serve as a highly specific and efficient orthogonal tool for assessing the quality of GSH pharmaceuticals, providing both qualitative and quantitative information on GSH and its related impurities A-D.

[Epidemiological investigation of iron deficiency among preschool children in 10 provinces, autonomous regions, or municipalities in China]

Objective: To understand the current status of anemia, iron deficiency, and iron-deficiency anemia among preschool children in China. Methods: A cross-sectional study was conducted with a multi-stage stratified sampling method to select 150 streets or townships from 10 Chinese provinces, autonomous regions, or municipalities (East: Jiangsu, Zhejiang, Shandong, and Hainan; Central: Henan; West: Chongqing, Shaanxi, Guizhou, and Xinjiang; Northeast: Liaoning). From May 2022 to April 2023, a total of 21 470 children, including community-based children aged 0.5 to<3.0 years receiving child health care and kindergarten-based children aged 3.0 to<7.0 years, were surveyed. They were divided into 3 age groups: infants (0.5 to<1.0 year), toddlers (1.0 to<3.0 years), and preschoolers (3.0 to<7.0 years). Basic information such as sex and date of birth of the children was collected, and peripheral blood samples were obtained for routine blood tests and serum ferritin measurement. The prevalence rates of anemia, iron deficiency, and iron-deficiency anemia were analyzed, and the prevalence rate differences were compared among different ages, sex, urban and rural areas, and regions using the chi-square test. Results: A total of 21 460 valid responses were collected, including 10 780 boys (50.2%). The number of infants, toddlers, and preschoolers were 2 645 (12.3%), 6 244 (29.1%), and 12 571 (58.6%), respectively. The hemoglobin level was (126.7±14.8) g/L, and the serum ferritin level was 32.3 (18.5, 50.1) μg/L. The overall rates of anemia, iron deficiency, and iron-deficiency anemia were 10.4% (2 230/21 460), 28.3% (6 070/21 460), and 3.9% (845/21 460), respectively. The prevalence rate of anemia was higher for boys than for girls (10.9% (1 173/10 780) vs. 9.9% (1 057/10 680), χ2=5.58, P=0.018), with statistically significant differences in the rates for infants, toddlers and preschoolers (18.0% (475/2 645), 10.6% (662/6 244), and 8.7% (1 093/12 571), respectively, χ2=201.81, P<0.01), and the rate was significantly higher for children in rural than that in urban area (11.8% (1 516/12 883) vs. 8.3% (714/8 577), χ2=65.54, P<0.01), with statistically significant differences in the rates by region (χ2=126.60, P<0.01), with the highest rate of 15.8% (343/2 173) for children in Central region, and the lowest rate of 5.3% (108/2 053) in Northeastern region. The prevalence rates of iron deficiency were 33.8% (895/2 645), 32.2% (2 011/6 244), and 25.2% (3 164/12 571) in infants, toddlers, and preschoolers, respectively, and 30.0% (3 229/10 780) in boys vs. 26.6% (2 841/10 680) in girls, 21.7% (1 913/8 821), 40.0% (870/2 173), 27.1% (2 283/8 413), 48.9% (1 004/2 053) in Eastern, Central, Western, and Northeastern regions, respectively, and each between-group showed a significant statistical difference (χ2=147.71, 29.73, 773.02, all P<0.01). The prevalence rate of iron-deficiency anemia showed a significant statistical difference between urban and rural areas, 2.9% (251/8 577) vs. 4.6% (594/12 883) (χ2=38.62, P<0.01), while the difference in iron deficiency prevalence was not significant (χ2=0.51, P=0.476). Conclusions: There has been a notable improvement in iron deficiency and iron-deficiency anemia among preschool children in China, but the situation remains concerning. Particular attention should be paid to the prevention and control of iron deficiency and iron-deficiency anemia, especially among infants and children in the Central, Western, and Northeastern regions of China.

[Analysis of the difference in metabolites and gene expressions between pre-receptive and receptive endometria]

OBJECTIVE

To analyze the difference in the gene expression, amino acid and carnitine levels in the cervical secretions between the endometria of pre-receptive and receptive stages, with an aim to provide clues for identifying new molecular markers for endometrial receptivity.

METHODS

Fifty nine infertile women treated at the Department of Reproductive Medicine of Linyi People's Hospital from January 6, 2020 to January 31, 2022 were selected as as the study subjects, which were matched with 3 pairs (6 cases) of infertile women preparing for embryo transfer based on factors such as age, body mass index, and length of infertility. Endometrial tissue samples were collected for gene transcription and expression analysis. Twenty five women who had become pregnant through assisted reproductive technology were selected as the control group, and 28 non-pregnant women receiving ovulation monitoring at the Outpatient Department were enrolled as the case group. Status of endometrial receptivity was determined by ultrasonography. In the former group, endometrial tissues were sampled for sequencing, and GO and KEGG database enrichment analysis of differentially expressed genes was carried out. In the latter group, cervical secretions were collected, and amino acid and carnitine levels were measured by mass spectrometry. Statistical analysis was carried out using rank sum test, t test and chi-square test with SPSS v25.0 software.

RESULTS

No difference was found in the clinical data of the patients with regard to age, body mass index, infertility years, AMH, FSH, LH, E2, and type of infertility. Compared with the receptive endometrial tissues, there were 100 significantly up-regulated genes and 191 significantly down-regulated genes in the pre-receptive endometrial tissue, with the most significantly altered ones being HLA-DRB5 and MMP10. The biological processes, molecular functions and pathways enriched by more differentially expressed genes in GO and KEGG were mainly immune regulation, cell adhesion and tryptophan metabolism. Analysis of secretion metabolism also revealed a significant difference in the levels of amino acids and carnitine metabolites between the two groups (P < 0.05), in particular those of Alanine, Valine, 3-hydroxybutyrylcarnitine (C4OH) + malonylcarnitine (C3DC)/captoylcarnitine (C10).

CONCLUSION

A significant difference has been discovered in the levels of gene transcription and protein expression in the endometrial tissues from the pre-receptive and receptive stages. The levels of amino acids and carnitine, such as Alanine, Valine, 3-hydroxybutyryl carnitine (C4OH)+malonyl carnitine (C3DC)/caproyl carnitine (C10), may be associated with the receptive status of the endometrium, though this need to be verified with larger samples.

The occurrence and abundance of antibiotic resistance genes in rivers of tropical islands: a case of Hainan Island, China

In this study, the occurrence and distribution of 49 antibiotic resistance genes (ARGs) and two integrase genes (intl1, intl2) in three major rivers of Hainan Island, China, were investigated in July 2021, and to explore the spatial distribution of the target genes in the three rivers with the potential influencing factors such as regional characteristics and environmental factors. The results showed that a total of 46 ARGs and two integrase genes were detected in water and sediment, and the absolute abundance of ARGs ranged from 1.16 × 103 to 2.97 × 107 copies/L and 3.34 × 103-1.55 × 107 copies/g. ARGs of macrolides, aminoglycosides, and sulfonamides were this study's main types of ARGs. The aadA2, tetE, ermF, tetX, aac(6')-Ib, tetW, and qnrS genes are predominant ARGs in the water and sediment of the three rivers. The relative abundance of ARGs shows higher abundance in the midstream and downstream and lower abundance in the upstream and estuarine. After conducting a correlation analysis, it was found that there was a significant positive correlation between the ARGs detected in the water of the three main rivers. However, in sediment, tetC was negatively correlated with tetQ, macB was negatively correlated with ermF and ereA (p < 0.05), while the remaining ARGs showed positive correlations. Specifically, there was no significant positive correlation between tetQ and tetC, macB and ereA, and ermF in the sediments. Among the nine environmental factors studied, pH was found to be the main factor associated with the occurrence of ARGs in the aquatic environment, but it was also significantly associated with only nine ARGs. Among the detected heavy metals, only Cd and Zn showed significant correlations with the two ARGs in the water bodies of the three main rivers. It indicated that the pollution of ARGs in the three major rivers was in the initial stage, the detection abundance was low, the influence of environmental factors was small, and the interaction between ARGs seemed to be the main driving force. This study provides a scientific basis for further understanding the occurrence of ARGs and their influencing factors in a tropical island environment, and lays a foundation for subsequent management.

[Characteristics of serum bile acids among healthy children in Zhejiang province]

Objective: To characterize the serum bile acid profiles of healthy children in Zhejiang Province. Methods: A cross-sectional study was conducted on 245 healthy children who underwent imaging and laboratory biochemical tests during routine physical examinations at the Children's Hospital of Zhejiang University School of Medicine from January 2020 to July 2022. Overnight fasting venous blood samples were collected, and the concentrations of 18 individual bile acids in the serum were accurately quantitated using tandem mass spectrometry. The concentration difference of bile acid were compared between different genders and to explore the correlation between age and bile acid levels. Used the Mann-Whitney U test for intergroup comparison and Spearman test to correlation analysis. Results: A total of 245 health children with a age of 10 (8, 12) years including 125 boys and 120 girls. There were no significant differences in levels of total bile acids, primary and secondary bile acids, free and conjugated bile acids between the two gender groups (all P>0.05). The serum concentrations of ursodeoxycholic acid and glycoursodeoxycholic acid in girls were significantly higher than those in boys (199.0 (66.9, 276.5) vs. 154.7 (49.3, 205.0) nmol/L, 274.0 (64.8, 308.0) vs. 181.0 (43.8, 209.3) nmol/L, Z=2.06, 2.71, both P<0.05). The serum taurolithocholic acid in both boys and girls were positively correlated with age (r=0.31, 0.32, both P<0.05). The serum chenodeoxycholic acid and glycochenodeoxycholic acid in the boys group were positively correlated with age (r=0.20, 0.23, both P<0.05), whereas the serum tauroursodeoxycholic acid in the girls group was negatively correlated with age (r=-0.27, P<0.05), and the serum cholic acid was positively correlated with age (r=0.34, P<0.05). Conclusions: The total bile acid levels are relatively stable in healthy children in Zhejiang province. However, individual bile acids showed gender differences and were correlated with age.

The fate of antibiotic resistance genes in the coastal lagoon with multiple functional zones

Coastal lagoons provide many important services to human society, but their year-round use for aquaculture introduces large amounts of sewage. The contamination of antibiotic resistance genes (ARGs) is therefore of great concern. In this study, 50 ARGs subtypes, two integrase genes (intl1, intl2), and 16S rRNA genes were detected by high-throughput quantitative PCR, and standard curves of all target genes were prepared for quantification. The occurrence and distribution of ARGs in a typical coastal lagoon (XinCun lagoon, China) were comprehensively explored. We detected 44 and 38 subtypes of ARGs in the water and sediment, respectively, and discuss the various factors influencing the fate of ARGs in the coastal lagoon. Macrolides-lincosamides-streptogramins B was the primary ARG type, and macB was the predominant subtype. Antibiotic efflux and antibiotic inactivation were the main ARG resistance mechanisms. The XinCun lagoon was divided into eight functional zones. The ARGs showed a distinct spatial distribution owing to the influence of microbial biomass and anthropogenic activity in different functional zones. Fishing rafts, abandoned fish ponds, the town sewage zone, and mangrove wetlands provided a large quantity of ARGs to the XinCun lagoon. Nutrients and heavy metals also significantly correlated with the fate of the ARGs, especially NO₂^--N and Cu, which cannot be ignored. It is noteworthy that lagoon-barrier systems coupled with persistent pollutant inputs result in coastal lagoons acting as a "buffer pool" for ARGs, which can then accumulate and threaten the offshore environment.

Weekly cumulative extracurricular core training time predicts cadet physical performance: A descriptive epidemiological study

Background

Core training can enhance athletic performance by enhancing core strength and stability. To achieve this outcome, however, a tailored training program is required; the normal military training curriculum is inadequate. The connection between cumulative weekly extracurricular training time, cumulative weekly extracurricular core training time and cadet performance is unknown.

Methods

The association between cumulative weekly extracurricular training time, cumulative weekly extracurricular core training time and performance has been discovered using a descriptive epidemiological study methodology. Questionnaires were used to collect information on personal characteristics and weekly cumulative extracurricular (core) training time, as well as the results of the Chinese Army Physical Fitness Test (C-APFT), which included 100-m dash, 5000-m run, 3000-m armed training run, 400-m steeplechase, 800 m breaststroke, horizontal bar pull-ups, 2-min sit-ups, 2-min push-ups, and hand grenade throwing. This study recruited two hundred and twenty male cadets (aged 18 to 23 years, 19.68 ± 0.91) from a military medical university.

Results

(a) The correlation between cumulative weekly extracurricular training time and C-APFT score is significant. The 100-m dash, 5000-m run, 3000-m armed training run, 400-m steeplechase, and 2-min push-ups performed the best when participants exercised for 5 to 10 h per week. (b) The number of cadets scoring good or excellent on the C-APFT improves with cumulative weekly extracurricular core training time. The recommended amount of core training for cadets per week is 120 min. (c) The average cumulative weekly extracurricular core training time was a effective predictor of performance on the 400-m steeplechase (R2 = 0.470, F = 10.641, P＜0.01), horizontal bar pull-ups (R2 = 0.238, F = 68.191, P＜0.01), 2-min sit-ups (R2 = 0.280, F = 84.710, P＜0.01), 100-m run (R2 = 0.031, F = 6.920, P＜0.01), 3000-m armed training run (R2 = 0.025, F = 5.603, P＜0.05), 2-min push-ups (R2 = 0.019, F = 4.295, P＜0.05), and hand grenade tossing (R2 = 0.025, F = 5.603, P＜0.05).

Conclusions

Active participation in extracurricular core training can improve cadets' C-APFT scores. An average cumulative weekly extracurricular training duration of 5-10 h showed the most progress, and more than 120 min per week was ideal for extracurricular core training. The amount of extracurricular time spent on core training exercises each week can be used as a predictor of the C-APFT.

CGI-58 Protein Acts as a Positive Regulator of Triacylglycerol Accumulation in Phaeodactylum tricornutum

Comparative gene identification-58 (CGI-58) is an activating protein of triacylglycerol (TAG) lipase. It has a variety of catalytic activities whereby it may play different roles in diverse organisms. In this study, a homolog of CGI-58 in Phaeodactylum tricornutum (PtCGI-58) was identified. PtCGI-58 was localized in mitochondria by GFP fusion protein analysis, which is different from the reported subcellular localization of CGI-58 in animals and plants. Respectively, PtCGI-58 overexpression resulted in increased neutral lipid content and TAG accumulation by 42-46% and 21-32%. Likewise, it also increased the relative content of eicosapentaenoic acid (EPA), and in particular, the EPA content in TAGs almost doubled. Transcript levels of genes involved in de novo fatty acid synthesis and mitochondrial β-oxidation were significantly upregulated in PtCGI-58 overexpression strains compared with wild-type cells. Our findings suggest that PtCGI-58 may mediate the breakdown of lipids in mitochondria and the recycling of acyl chains derived from mitochondrial β-oxidation into TAG biosynthesis. Moreover, this study potentially illuminates new functions for CGI-58 in lipid homeostasis and provides a strategy to enrich EPA in algal TAGs.

The reasons for the spatial and media distribution variations of ARGs in a typical semi-enclosed bay

Antibiotic resistance genes (ARGs) are considered a newly emerging contaminant. This study aimed to investigate the spatial and media distribution patterns of ARGs in Jiaozhou Bay, as well as the reasons behind these patterns. The results revealed that aminoglycoside and MLSB resistant genes predominated in all samples, and the relative abundance of ARGs ranging from 10^-6 to 10^-2, 10^-6 to 10^-3 and 10^-5 to 10^-2 copies/16S rRNA in coastal water, bay water, and sediments, respectively. The significant spatial variation of ARGs was explained by the fact that the coastal water was more susceptible to human activities, whereas environmental physicochemical factors played a crucial role in the bay water. The intrinsic reason for the media distribution variation was the different assembly processes in the two media, while the external reason was that the ARGs in the water and sediments were mainly influenced by environmental physicochemical factors and heavy metals, respectively.

Serum proteomics analysis of biomarkers for evaluating clinical response to MTX/IGU therapy in early rheumatoid arthritis

Methotrexate (MTX) and iguratimod (IGU) are conventional synthetic disease modifying antirheumatic drugs widely used in the treatment of Rheumatoid arthritis (RA) in China. Although MTX combined with IGU can significantly inhibit the progression of RA, some patients do not respond to the treatment. The purpose of this study is to explore the difference of serum protein expression between RA patients with good and poor response to the combined therapy by label-free quantitative proteomic approach. From the proteomics data, a total of 782 proteins in the serum of RA patients were detected, and of which 9 were upregulated and 18 were downregulated in the good response group compared to poor response group. Among them, four significantly differentially expressed proteins (RELN, LDHA, MRC1 and TKT) were further validated by multiple reaction monitoring (MRM)-based quantification approach, and three of them (RELN, LDHA and MRC1) were confirmed to be correlated with the response to MTX/IGU therapy. Logistic regression and ROC analysis indicated that the combination of RELN, LDHA and MRC1 had good performance in evaluating the response. This result proved the different serum proteins signature fingerprint between response group and non-response group; and highlighted the potential of the label-free and mass spectrometry-based quantitative proteomic approach in screening biomarkers for evaluating clinical response to MTX/IGU therapy in RA.

[Research progress of infrared light promoting wound healing]

At present, current stimulation, ultra-sound, and light therapy have become effective methods to promote wound healing. Among them, infrared light is the most widely used method and is one of the important methods to promote wound healing. The therapeutic effect of infrared light on wounds is related to the effect of photobiomodulation on cells and molecules on the skin surface, but the mechanism by which photobiomodulation of infrared light promotes wound healing has not been fully elucidated. Therefore, it is necessary to study the action characteristics and the mechanism of photo-biomodulation of infrared light in promoting wound healing. This article reviews the effect of different types of infrared light on wound healing and the mechanism of infrared light in promoting wound healing.

POS0071 THE EFFICACY OF PIRFENIDONE COMBINED WITH IMMUNOSUPPRESSANT THERAPY IN THE CONNECTIVE TISSUE DISEASE-ASSOCIATED PULMONARY INTERSTITIAL DISEASE, A 24-WEEK PROSPECTIVE CONTROLLED COHORT STUDY

Background

Pulmonary interstitial disease(ILD)is very common in connective tissue disease (CTD). Different subtypes display significant differentiations in prognosis. Pirfenidone (PFD), the targeted anti-fibrosis and anti-inflammatory drug, started to apply in CTD-ILD, while its strategy of combination with immunotherapy, bridging time and service time are worth discussing.

Objectives

To evaluate the efficacy and safety of PFD combined with immunosuppressant (IS) in the treatment of several CTD- ILD.

Methods

111 CTD-ILD patients were involved from Aug 2019 to Dec 2021 (ClinicalTrials.gov Identifier NCT04928586), including systemic sclerosis (SSc, n=30), inflammatory myopathy (IIM, n=51), rheumatoid arthritis (RA, n=17) and other CTDs (such as systemic lupus erythematosus, sjogren’s syndrome, n=13). Patients were treated with relative stable dose of glucocorticoid (GC) and/or IS since screening.After the evaluation of HRCT, pulmonary function (FVC% and DLCo%) and basic disease activity, PFD was added or not and followed up regularly for 24 weeks. The changes of lung function and imaging were recorded in different subgroups.

Results

At baseline, The FVC% in the SSc-PFD (n=14), IIM-PFD (n=25) pts were lower than that of SSc-no-PFD (n=16), IIM-no-PFD (n=26) respectively, that was 81.06 vs 99.63(p = 0.014), 78.23 vs 91.12, (p= 0.010). And IIM-PFD group present a lower baseline DLCo% than IIM-no-PFD pts (64.25 vs 72.82, p =0.034). DLCo% in the other CTDs was lower than SSc, IIM, RA pts (54.58 vs 65.55, 68.71, 66.89, p=0.036), while there were no significant differences in baseline FVC% among these disease.

After 24 weeks of treatment, FVC% in SSc-PFD group was improved by 7.15%, while that was -0.91% in SSc-no-PFD pts (p=0.042). The elevation in FVC% was also significant between the IIM-PFD and IIM-no-PFD control (8.00 vs 1.40, p=0.016). On the other hand, DLCo% of RA-PFD obviously enhanced 7.40%, compared with RA-no-PFD decrease 5.50% from baseline(p=0.002) (Figure 1).

Figure 1.

The changes of FVC% and DLco% in PFD treated CTD-ILD for 24 weeks. (A) FVC% changes in SSc, IIM, RA and other CTD-ILD from baseline.; (B) DLco% changes in SSc, IIM, RA and other CTD-ILD from baseline. * p< 0.05, compared to no PFD treatment group.

When performing subgroup analysis with manifestations in HRCT, the change of FVC% in SSc-PFD pts with usual interstitial pueumonia tendency(SSc-PFD-UIP) was higher than SSc-PFD-non-UIP group (8.05 vs -3.20, p=0.014). However, the non-UIP tendency in IIM-PDF pts displayed superior therapeutic effects than IIM-PDF-UIP pts (10.50 vs 1.00, p=0.005). In addition, DLCo% improved significantly in RA-PDF-non-UIP subgroup, compared with RA-PDF-UIP pts (10.40 vs -4.45, p=0.017).

According to whether the baseline FVC% and DLCo% value was less than 70%, the improvement of FVC% was significantly higher in PFD treatment group than no-PFD pts of SSc and IIM with baseline High-FVC%(6.60 vs 0.10, p=0.047),(6.30 vs 1.10, p= 0.089).In RA-PFD pts, DLCo% showed a significant increase in baseline DLCo% less than 70% subgroup, compared to RA-no-PDF (7.40% vs -6.60%, p=0.011).The basic IS were considerable between PFD andno-PFD pts throughout the study and no differences of GS and IS dosages at baseline and follow up among all subgroups.

Multiple linear regression analysis found that baseline FVC%<70%(HR=4.56,6.81) and prescription of PFD(HR=4.56,4.37) could positively affect the changes of FVC% and DLCo% (all p<0.05).

Conclusion

The response of pulmonary function to PFD were varied in different CTD-ILD subsets. SSc and IIM pts acquired obviously improvement on FVC%, especially with high baseline FVC group. DLco% elevated in RA-PFD, highlight those baseline Low-DLco and No-UIP pts.

Acknowledgements

Funded by ECCM Program of Clinical Research Center of Shandong University (No. 2021SDUCRCB010)

Disclosure of Interests

None declared

POS0558 A INFLAMMATORY FACTOR-BASED NOMOGRAM PREDICTS FIRST REMISSION TIME OF RHEUMATOID ARTHRITIS PATIENTS WITH BASELINE GALECTIN-9

Background

Rheumatoid arthritis (RA) is an autoimmune disease. The core treatment principle of RA is to achieve remission or low disease activity as soon as possible to ensure optimal outcomes. Predicting the first remission time according to the patient’s risk factors is very important for the choice of treatment scheme.

Objectives

We aimed to verify the prognostic value of inflammatory factors in RA and establish a nomogram based on Human Interleukin-6(IL-6), Galectin-9(Gal-9)and disease activity to predict the first remission time after conventional synthetic DMARDstreatment.

Methods

184 RA active patients(DAS28-ESR> 3.2, ACR 1987 criteria or EULAR 2010 criteria) were enrolled in the rheumatology department of Qilu Hospital of Shandong University from June 2014 to June 2020.129 patients were assigned to the development cohort and 55 patients were assigned to the validation cohort randomly. Baseline clinical data and plasma were collected. The expressions of Tumour Necrosis Factor α (TNF-α), Vascular Endothelial Growth Factor (VEGF), IL-6 and Gal-9 in plasma of RA patients were detected by ELISA. All patients were treated with csDMARDs and we recorded activity of each follow-up visit until 36 months. Lasso regression and Cox regression analysis were used to screen the 14 variables (including activity indices and cytokines) at baseline, and the prediction model was established to draw the nomogram.

Results

Patient age, CRP, IL-6, Gal-9, HAQ and DAS28-ESR were the significant prognostic factors in the lasso and Cox regression analyses, especially Gal-9. The multivariate analysis revealed that IL-6≤ 9.04 pg/ml(HR =0.54, 95% CI:0.31–0.95), Gal-9≤ 4490 pg/ml(HR =0.43, 95% CI:0.21–0.89) were independent protective factors (Table 1). Above-mentioned six factors were included in our model as predictors (Figure 1). The resulting model containing six factors had good discrimination ability in both the development cohort (C-index, 0.729) and the validation cohort (C-index, 0.710). Time-dependent ROC curve (Figure 2), calibration analysis (Figure 3) and decision curve analysis (DCA) show that the nomogram has significant discriminant power, stability and clinical practicability in predicting the first remission time.

Conclusion

We constructed and validated a nomogram with baseline activity indices and cytokines that can predict first remission time in RA patients after csDMARDs treatment. Using this simple-to-use model with plasma Gal-9 at baseline, the remission rate can be determined for an individual patient and could be useful for the early identification of high-risk patients.

References

[1]SUN J, SUI Y, WANG Y, et al. Galectin-9 expression correlates with therapeutic effect in rheumatoid arthritis [J]. Scientific reports, 2021, 11(1): 5562.

[2]ZHANG L, CHEN F, GENG S, et al. Methotrexate (MTX) Plus Hydroxychloroquine versus MTX Plus Leflunomide in Patients with MTX-Resistant Active Rheumatoid Arthritis: A 2-Year Cohort Study in Real World [J]. Journal of inflammation research, 2020, 13: 1141-50.

[3]FORNARO M, CACCIAPAGLIA F, LOPALCO G, et al. Predictors of long-term clinical remission in rheumatoid arthritis [J]. European journal of clinical investigation, 2021, 51(2): e13363.

Acknowledgements

Funded by ECCM Program of Clinical Research Center of Shandong University (No. 2021SDUCRCB010)

Disclosure of Interests

None declared.

POS0555 THE NON-APOPTOTIC PROGRAMMED-CELL-DEATH-RELATED SIGNATURE PREDICTS ANTI-TNF THERAPY NONRESPONSE IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background

EULAR guideline in rheumatoid arthritis (RA) recommended the primary failure of the first-line conventional synthetic modifying anti-rheumatic drugs (csDMARDs) patients switching to tumor necrosis factor alpha inhibitors (TNFi) [1]. Nevertheless, approximately 30-40% csDMARDs-IR patients also experience inefficacy of TNFi [2]. There is still no index to predict whether TNFi would be responded or not. Moreover, only few studies had focused on the relationship between TNFi nonresponse and other cell programmed deaths except apoptosis.

Objectives

To predict the possibility of TNFi response prior to prescript in RA patients with the biomarkers of non-apoptotic programmed cell death in synovial cells.

Methods

The datasets of 22 TNFi treated RA synovial samples were enrolled from the Gene Expression Omnibus (GEO) database (GSE140036 and GSE15602). And the differentially expressed genes (DEGs) and modules related to TNFi treatment through weight gene correlation network analysis (WGCNA) were identified with the R packages “limma” and “WGCNA”. Then the enrichment analysis among the shared genes was performed through the R.4.1.2, Metascape website, and WebGestalt website. Following with the confirmation of the non-apoptotic programmed cell death (NAPCD) genes in the shared genes with Student’s T-Test. Furthermore, the TNFi treatment cohort was clustered based on the hub genes, making the receiver operating characteristic (ROC) curve analysis. Moreover, the least absolute shrinkage and selection operator (LASSO) model was constructed to identify the predictive genes.

Results

2624 DEGs were identified significantly, including 161 upregulated genes and 2463 downregulated genes. One module with TNFi treatment was constructed in WGCNA, significant in both response and nonresponse. Then the gene signatures for TNFi nonresponse were collected from overlaps 2260 genes in above. And we found 38 NAPCD genes might play role in TNFi nonresponse, but reserved 33 genes which statistically significant with T-Test. 22 TNFi treated synovial samples in GEO database could be classified into response or nonresponse subgroups. The ROC curve showed that the AUC for 32 genes in these samples ranged from 0.7 to 0.9, expected for CD46. At last, the LASSO model indicated that CASP5, CAPN10, ITGB4, NLRP2, and SLC2A8 could predict the TNFi nonresponse, as the risk score = CASP5 × 0.028 + CAPN10 × 0.064 + ITGB4× 0.080+ NLRP2 × 0.317+ SLC2A8 × 0.090 (Figure 1).

Figure 1.

Predictive model of TNFi nonresponse based on NAPCD genes. (A) Volcano map of differential expressed genes; (B) Correlation heat map of gene modules and phenotypes, the red is positively correlated with the phenotype, blue is negatively correlated with the phenotype; (C) The shared 38 genes of TNFi response & nonresponse DEGs, among the WGCNA turquoise module and cell programmed death genes; (D) Consensus clustering matrix for k = 2; (E) The ROC curve of 33 genes; (F) LASSO regression of the 32 genes,except for CD46; (G) Nomogram for predicting TNFi nonresponse in TNFi treatment RA cohort, indicated five possible indicators (CASP5, CAPN10, ITGB4, NLRP2, and SLC2A8) were closely related to TNFi nonresponse.

Conclusion

Our study firstly screened out the 38 NAPCD candidate genes signatures in RA synovial tissues which took part in TNFi nonresponse through WGCNA and DEGs. Further analysis confirmed that five possible indicators (CASP5, CAPN10, ITGB4, NLRP2, and SLC2A8) were closely related to TNFi nonresponse.

References

[1]van Delft MAM, Huizinga TWJ: An overview of autoantibodies in rheumatoid arthritis. Journal of autoimmunity 2020, 110:102392.

[2]Aletaha D: Precision medicine and management of rheumatoid arthritis. Journal of autoimmunity 2020, 110:102405.

Acknowledgements

Funded by ECCM Program of Clinical Research Center of Shandong University.

Disclosure of Interests

None declared.

AB0407 EFFICACY AND SAFETY OF 144-WEEK TREATMENT WITH TACROLIMUS AS THE FIRST-LINE CONVENTIONAL SYNTHETIC DISEASE-MODIFYING ANTIRHEUMATIC DRUG (csDMARD) FOR PATIENTS WITH ACTIVE REFRACTORY RHEUMATOID ARTHRITIS： A PROSPECTIVE, COHORT STUDY

Background

The T2T guideline in RA recommended the normal csDMARDs irresponsive patients (pts) switching to other treatment target. Tacrolimus (TAC), the inhibitor of T cell activation, is candidate for these pts, especially with extrarticular complications (EC).

Objectives

To observe the efficacy and safety of TAC-based csDMARDS regimen refractory RA (RRA) pts and the characteristics of TAC combined treatment.

Methods

This prospective cohort study (ClinicalTrials.gov Identifier NCT02837978) was conducted in China. According to baseline DAS28-ESR, RRA pts (ACR 1987 criteria [1]) were classified to severe (>5.1, S) or moderate (> 3.2,≦5.1, M) groups. The efficacy indicators and AE were recorded untill 144w.

The combined medicine with TAC was based on the past history of csDMARD prescription and EC, including TAC with/wo MTX (T+M or T group), Pred, HCQ.

Results

150 pts (52±14y) were involved, 15 finished 144w observation, 50 still following up and 85 lost.

As shown with GEE analysis, DAS28-ESR, CRP, HAQ were decreased significantly in all pts within 24ws, and maintained stable in later period (Figure 1). The REM or LDA, achieved ACR20, good or moderate EULAR response (G+M) proportion of 103 pts completed the 24w were 41.75%, 56.31%, 76.70%.

Figure 1.

Disease activity index of 150 RRA pts decreased in 144weeks

Similar to the Japanese study [2], DAS28-ESR, CRP and HAQ typically declined rapidly in S group, but still higher than M (Figure 2A-C). According to GBTM analysis, S group, longer disease course or higher HAQ had a higher ACR20 remission rate (Figure 2D).

Figure 2.

Disease activity index of 103 pts declined rapidly in 24weeks.

(A). DAS28-ESR; (B) CRP; (C). HAQ declined significantly in S (n=53) than M (n=50) during 24ws. (D).higher increased ACR20 remission group (90.6%), compared with low-stable (0%) in 24ws. *p< 0.05, compared to M; #p< 0.05, compared to baseline.

A total of 69 RA pts (46.0%) had 177 times (23.07%) AE, including 2 SAEs. Infection was the dominating AE (30%) due to asymptomatic positive urinary leucocyte and cold were classified, higher than (3.4%) Japanese study [3]. AEs were mainly happened in pts with higher TAC blood concentration 4.55(3-14.5) ng/ml, compared to No AE group 3.8(2.4-7.8) ng/ml, p=0.048, extremely in those abnormal glucose tolerance and hypertensive pts, p=0.002, 0.022.

The most common reasons of lost were drug ineffective (32.94%), economic reasons (29.1%). There was no difference in efficacy of TAC combined treatment. Combination MTX reduce AE, decrease the usage rate and dosage of Pred. Combination Pred increased AE.

Pts that achieved REM+LDA, G+M, had better TAC survival rate (Figure 3A-B). The combination of MTX, HCQ reduce lost rate (Figure 3C-D).

Figure 3.

TAC survival ratio were compared in different response and csDMARDs combination groups.

(A).The pts acquired remission (n= 31) or LDA (n= 18) had higher TAC survival rate than high (n=28) & moderate (n=73) group, * p < 0.05, compared to group High; # p < 0.05, compared to Moderate; & p < 0.05, compared to Low; (B). The pts G+M (n=95) had better TAC survival rate, compared with no response (N, n=55), ** p < 0.01; (C). Combine MTX reduced lost rate, ** p < 0.01, compared to T; (D). Combine MTX and HCQ reduced lost rate, * p < 0.05 compared to MTX-HCQ-; # p < 0.05 compared to MTX+HCQ-.

The Logistic regression showed baseline DAS28-ESR was an independent protective factor for poor response. Baseline DAS28-ESR and previous Perd use were independent protective factors for ACR20 remission.　

Conclusion

TAC-based combined therapies are effective and tolerable for RRA, especially to the higher disease activity pts. TAC blood concentration related to AE. The lower disease activity index and better respond, the higher TAC survival ratio. MTX is recommended as TAC combined treatment.

References

[1]Levin RW, et al. Scand J Rheumatol 1996, 25(5):277-281.

[2]Kanzaki T,et al., Rheumatology International,2013. 33(4):871-877.

[3]Takeuchi T, et al. Mod Rheumatology 2018,28(1): 48-57.

Acknowledgements

Acknowledgements: Funded by ECCM Program of Clinical Research Center of Shandong University (No. 2021SDUCRCB010)

Disclosure of Interests

None declared

Promoter variation in a homeobox gene, CpDll, is associated with deeply lobed leaf in Cucurbita pepo L

CpDll, encoding an HD-Zip I transcription factor, positively regulates formation of deeply lobed leaf shape in zucchini, Cucurbita pepo, which is associated with sequence variation in its promoter region. Leaf shape is an important horticultural trait in zucchini (Cucurbita pepo L.). Deeply lobed leaves have potential advantages for high-density planting and hybrid production. However, little is known about the molecular basis of deeply lobed leaf formation in this important vegetable crop. Here, we conducted QTL analysis and fine mapping of the deeply lobed leaf (CpDll) locus using recombinant inbred lines and large F₂ populations developed from crosses between the deeply lobed leaf HM-S2, and entire leaf Jin-GL parental lines. We show that CpDll exhibited incomplete dominance for the deeply lobed leaf shape in HM-S2. Map-based cloning provided evidence that CpCll encodes a type I homeodomain (HD)- and Leu zipper (Zip) element-containing transcription factor. Sequence analysis between HM-S2 and Jin-GL revealed no sequence variations in the coding sequences, whereas a number of variations were identified in the promoter region between them. DUAL-LUC assays revealed significantly stronger promoter activity in HM-S2 than that in Jin-GL. There was also significantly higher expression of CpDll in the leaf base of deeply lobed leaves of HM-S2 compared with entire leaf Jin-GL. Comparative analysis of CpDll gene homologs in nine cucurbit crop species (family Cucurbitaceae) revealed conservation in both structure and function of this gene in regulation of deeply lobed leaf formation. Our work provides new insights into the molecular basis of leaf lobe formation in pumpkin/squash and other cucurbit crops. This work also facilitates marker-assisted selection for leaf shape in zucchini breeding.

Facile one-step fabrication of Cu-doped carbon dots as a dual-selective biosensor for detection of pyrophosphate ions and measurement of pH

High-performance determination of pyrophosphate ions (PPi) and pH is an important goal in biological systems. In this work, Cu-doped carbon dots (Cu-CDs) were synthesized rapidly and simply via a one-pot hydrothermal method. The as-obtained Cu-CDs, with an average size of 2.55 nm, exhibit an excitation-independent fluorescence emission and possess desirable functional groups of carboxyl and amine, which can be served as fluorescence nanoprobes for detection of PPi based on surface passivation. Under the optimal condition, the linear range for detection of PPi was 0.05-20 µM, and the corresponding limit of detection (LOD) was 0.013 µM, indicative of a promising assay for the PPi. Moreover, the fluorescent intensity of the Cu-CDs is linear against pH value from 6 to 8.7 in buffer solution, suggesting the feasibility as a pH sensor. The synthesized Cu-CDs coated fluorescent paper indeed can monitor pH in urine with satisfaction by naked eyes through ultraviolet irradiation. The successful detection of PPi and the visual detection of pH value suggest a highly promising application of Cu-CDs in the field of biosensing.

The Lipoteichoic Acid-Related Proteins YqgS and LafA Contribute to the Resistance of Listeria monocytogenes to Nisin

Listeria monocytogenes is a major pathogen contributing to foodborne outbreaks with high mortality. Nisin, a natural antimicrobial, has been widely used as a food preservative. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. A mariner transposon library was constructed in L. monocytogenes, leading to the identification of 99 genes associated with the innate resistance to nisin via Transposon sequencing (Tn-seq) analysis. To validate the accuracy of the Tn-seq results, we constructed five mutants (ΔyqgS, ΔlafA, ΔvirR, ΔgtcA, and Δlmo1464) in L. monocytogenes. The results revealed that yqgS and lafA, the lipoteichoic acid-related genes, were essential for resistance to nisin, while the gtcA and lmo1464 mutants showed substantially enhanced nisin resistance. Densely wrinkled, collapsed surface and membrane breakdown were shown on ΔyqgS and ΔlafA mutants under nisin treatment. Deletion of yqgS and lafA altered the surface charge, and decreased the resistance to general stress conditions and cell envelope-acting antimicrobials. Furthermore, YqgS and LafA are required for biofilm formation and cell invasion of L. monocytogenes. Collectively, these results reveal novel mechanisms of nisin resistance in L. monocytogenes and may provide unique targets for the development of food-grade inhibitors for nisin-resistant foodborne pathogens. IMPORTANCE Listeria monocytogenes is an opportunistic Gram-positive pathogen responsible for listeriosis, and is widely present in a variety of foods including ready-to-eat foods, meat, and dairy products. Nisin is the only licensed lantibiotic by the FDA for use as a food-grade inhibitor in over 50 countries. A prior study suggests that L. monocytogenes are more resistant than other Gram-positive pathogens in nisin-mediated bactericidal effects. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. Here, we used a mariner transposon library to identify nisin-resistance-related genes on a genome-wide scale via transposon sequencing. We found, for the first time, that YqgS and LafA (Lipoteichoic acid-related proteins) are required for resistance to nisin. Subsequently, we investigated the roles of YqgS and LafA in L. monocytogenes stress resistance, antimicrobial resistance, biofilm formation, and virulence in mammalian cells.

The dough-strengthening and spore-sterilizing effects of mannosylerythritol lipid-A in frozen dough and its application in bread making

Biosurfactants have been put into applications in breadmaking industry, while the effects of mannosylerythritol lipid-A (MEL-A) on gluten network of frozen dough, bread quality and microbial spoilage were firstly investigated in this study. Rheology and differential scanning calorimetry (DSC) analysis showed that MEL-A significantly improved the rheological properties of frozen dough and reduced the content of frozen water. Further experiments showed that MEL-A promoted the formation of aggregates by interacting with gluten protein, and strengthened the gluten network through molecular weight distribution measurement and microstructure observation, effectively avoiding the destruction of ice crystals. A series of bread assessments illustrated MEL-A improved the loaf volume, gas retention ability and textural property. In addition, MEL-A (1.5%) killed 99.97% of the vegetative cells of Bacillus cereus and 75.54% of the spores, and at the same time had a slight inactivation effect on yeast. These results indicate that MEL-A has broad application prospects in the baking industry and the storage stage of flour products.

One-step hydrothermal synthesis of nitrogen-doped carbon dots as a super selective and sensitive probe for sensing metronidazole in multiple samples

A reliable, super selective and sensitive nitrogen-doped carbon dots (N-CDs) nanoprobe that can quantitatively and quickly detect the concentration of metronidazole (MTZ) in multiple samples was built. We first prepared the N-CDs using N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC·HCl) as the precursor via a green, facile one-step hydrothermal method. The as-synthesized N-CDs were characterized by a variety of analytical and spectroscopic techniques, which revealed excitation-dependent fluorescence behavior with the maximum excitation and emission wavelengths being 335 and 370 nm, respectively. Significantly, the fluorescence emission of N-CDs underwent initial quenching upon the addition of MTZ via the inner filter effect (IFE), indicating a prospective detection method for MTZ. The linear range for MTZ detection was 0.1-250 μM, and the corresponding limit of detection (LOD) and limit of quantification (LOQ) were calculated to be only 70 nM and 233.33 nM, respectively. Moreover, due to the negligible cytotoxicity and superior biocompatibility, the fabricated N-CDs show a promising prospect for detecting MTZ in living cells. In general, our proposed N-CDs-based fluorescence sensing platform possesses super low LOD and LOQ values, wide linear range, and satisfactory selectivity, and can be applied to the detection of MTZ in multiple real samples.

Nitrogen and copper-doped carbon quantum dots with intrinsic peroxidase-like activity for double-signal detection of phenol

Herein, a simple and facile one-step hydrothermal carbonization synthesis procedure for the fabrication of N, Cu-doped carbon quantum dots (N, Cu-CQDs) as a peroxidase-mimicking enzyme was reported. The peroxidase-like performance of N, Cu-CQDs was assessed based on the oxidative coupling reaction of phenol with 4-aminoantipyrine (4-AAP) in the presence of hydrogen peroxide (H2O2). The N, Cu-CQDs/4-AAP/H2O2 system was applied to sensing phenol based on double signals of absorption spectra (or colorimetric visualization) as well as fluorescence spectra. The obtained limits of detection (LODs) were as low as 0.12 μM and 0.02 μM, respectively. Moreover, the proposed method was successfully applied to the determination of phenol in sewage with satisfactory recovery. Our results demonstrate that the N, Cu-CQDs/4-AAP/H2O2/phenol sensing system has a great potential prospect for applications in environmental chemistry and biotechnology.

POS0647 EFFICACY, SAFETY AND CHARACTERISTICS OF IGURATIMOD-BASED THERAPY IN THE TREATMENT OF UA, ERA AND RA PATIENTS FOR 24 WEEKS: A PROSPECTIVE COHORT STUDY

Background:

Experts emphasize early diagnosis and treatment in RA, but the widely used diagnostic criterias fail to meet the accurate judgment of early rheumatoid arthritis. In 2012, Professor Zhanguo Li took the lead in establishing ERA “Chinese standard”, and its sensitivity and accuracy have been recognized by peers. However, the optimal first-line treatment of patients (pts) with undifferentiated arthritis (UA), early rheumatoid arthritis (ERA), and rheumatoid arthritis (RA) are yet to be established.

Objectives:

To evaluate the efficacy and safety of Iguratimod-based (IGU-based) Strategy in the above three types of pts, and to explore the characteristics of the effects of IGU monotherapy and combined treatment.

Methods:

This prospective cohort study (ClinicalTrials.gov Identifier NCT01548001) was conducted in China. In this phase 4 study pts with RA (ACR 1987 criteria[1]), ERA (not match ACR 1987 criteria[1] but match ACR/EULAR 2010 criteria[2] or 2014 ERA criteria[3]), UA (not match classification criteria for ERA and RA but imaging suggests synovitis) were recruited. We applied different treatments according to the patient’s disease activity at baseline, including IGU monotherapy and combination therapies with methotrexate, hydroxychloroquine, and prednisone. Specifically, pts with LDA and fewer poor prognostic factors were entered the IGU monotherapy group (25 mg bid), and pts with high disease activity were assigned to combination groups. A Chi-square test was applied for comparison. The primary outcomes were the proportion of pts in remission (REM)or low disease activity (LDA) that is DAS28-ESR<2.6 or 3.2 at 24 weeks, as well as the proportion of pts, achieved ACR20, Boolean remission, and good or moderate EULAR response (G+M).

Results:

A total of 313 pts (26 pts with UA, 59 pts with ERA, and 228 pts with RA) were included in this study. Of these, 227/313 (72.5%) pts completed the 24-week follow-up. The results showed that 115/227 (50.7%), 174/227 (76.7%), 77/227 (33.9%), 179/227 (78.9%) pts achieved DAS28-ESR defined REM and LDA, ACR20, Boolean remission, G+M response, respectively. All parameters continued to decrease in all pts after treatment (Fig 1).

Compared with baseline, the three highest decline indexes of disease activity at week 24 were SW28, CDAI, and T28, with an average decline rate of 73.8%, 61.4%, 58.7%, respectively. Results were similar in three cohorts.

We performed a stratified analysis of which IGU treatment should be used in different cohorts. The study found that the proportion of pts with UA and ERA who used IGU monotherapy were significantly higher than those in the RA cohort. While the proportion of triple and quadruple combined use of IGU in RA pts was significantly higher than that of ERA and UA at baseline and whole-course (Fig 2).

A total of 81/313 (25.8%) pts in this study had adverse events (AE) with no serious adverse events. The main adverse events were infection(25/313, 7.99%), gastrointestinal disorders(13/313, 4.15%), liver dysfunction(12/313, 3.83%) which were lower than 259/2666 (9.71%) in the previous Japanese phase IV study[4].

The most common reasons of lost follow-up were: 1) discontinued after remission 25/86 (29.1%); 2) lost 22/86 (25.6%); 3) drug ineffective 19/86 (22.1%).

Conclusion:

Both IGU-based monotherapy and combined therapies are tolerant and effective for treating UA, ERA, and RA, while the decline in joint symptoms was most significant. Overall, IGU combination treatments were most used in RA pts, while monotherapy was predominant in ERA and UA pts.

References:

[1]Levin RW, et al. Scand J Rheumatol 1996, 25(5):277-281.

[2]Kay J, et al. Rheumatology 2012, 51(Suppl 6):vi5-9.

[3]Zhao J, et al. Clin Exp Rheumatol 2014, 32(5):667-673.

[4]Mimori T, et al. Mod Rheumatol 2019, 29(2):314-323.

Disclosure of Interests:

None declared

A study on the effects of regional differences on agricultural water resource utilization efficiency using super-efficiency SBM model

This study evaluated the water resource utilization efficiency and resource consumption for planting, forestry, animal husbandry, and fishery in various regions of China. Using the super-efficiency Slacks-Based Measure (SBM) analysis method, the main agricultural pollution emissions (Chemical Oxygen Demand, ammonia nitrogen, and agricultural carbon emissions) were proposed as environmental constraints for the first time. The threshold regression model was used to measure the impact of agricultural water use efficiency on agricultural water consumption by constructing seven different explanatory variables. The results show that the overall utilization efficiency of agricultural water resources in China presents a fluctuating downward trend, and the regional differences are significant. A single threshold effect on agricultural water consumption was found in five variables: per capita water resources, disposable income, dependence on foreign trade, industrial structure, and Gross Domestic Product. The increase in each parameter will have a positive effect on agricultural water consumption. The relationship between agricultural water use efficiency and agricultural water use was non-linear when the government's attention and the rural labor force were used as threshold variables.

Synergistic antibacterial and antibiofilm effects of ultrasound and MEL-A against methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is drug-resistant and biofilm-forming pathogenic bacteria with severe morbidity and mortality, and has been continuously detected in food products in recent years. Mannosylerythritol lipids (MELs) are novel biosurfactants and perform antibacterial property against gram-positive bacteria. Ultrasound has been applied into food sterilization as non-thermal techniques and has advantage of maintaining food nutrition and flavor over heat pasteurization. In this work, the synergistic treatment of ultrasound and MEL-A was used to combat planktonic cells and biofilm of MRSA. As a result, the combined treatment has exhibited remarkable antibacterial effect proved by enumeration of viable microbes. Furthermore, flow cytometry, scanning electron microscopy and transmission electron microscopy revealed ultrasound has enhanced the inhibitory effect of MEL-A through exacerbating cell membrane damage. On the other hand, the collaborating working modes to eradicate MRSA biofilm were disturbing cell adhesion to surface by MEL-A and destructing mature biofilm mechanically by ultrasound, reaching to over 90% of clearance rate. The findings of this study illustrated the synergistic antimicrobial mechanism of ultrasound and MEL-A treatments, and offered theoretical basis for their potential applications in food preservation.

Contributions of Glycolipid Biosurfactants and Glycolipid-Modified Materials to Antimicrobial Strategy: A Review

Glycolipid biosurfactants are natural amphiphiles and have gained particular interest recently in their biodegradability, diversity, and bioactivity. Microbial infection has caused severe morbidity and mortality and threatened public health security worldwide. Glycolipids have played an important role in combating many diseases as therapeutic agents depending on the self-assembly property, the anticancer and anti-inflammatory properties, and the antimicrobial properties, including antibacterial, antifungal, and antiviral effects. Besides, their role has been highlighted as scavengers in impeding the biofilm formation and rupturing mature biofilm, indicating their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction in vast hospital infections. Notably, glycolipids have been widely applied to the synthesis of novel antimicrobial materials due to their excellent amphipathicity, such as nanoparticles and liposomes. Accordingly, this review will provide various antimicrobial applications of glycolipids as functional ingredients in medical therapy.

A FOD Detection Approach on Millimeter-Wave Radar Sensors Based on Optimal VMD and SVDD

Foreign object debris (FOD) on airport runways can cause serious accidents and huge economic losses. FOD detection systems based on millimeter-wave (MMW) radar sensors have the advantages of higher range resolution and lower power consumption. However, it is difficult for traditional FOD detection methods to detect and distinguish weak signals of targets from strong ground clutter. To solve this problem, this paper proposes a new FOD detection approach based on optimized variational mode decomposition (VMD) and support vector data description (SVDD). This approach utilizes SVDD as a classifier to distinguish FOD signals from clutter signals. More importantly, the VMD optimized by whale optimization algorithm (WOA) is used to improve the accuracy and stability of the classifier. The results from both the simulation and field case show the excellent FOD detection performance of the proposed VMD-SVDD method.

Analysis of the Risk Factors for Nosocomial Bacterial Infection in Patients with COVID-19 in a Tertiary Hospital

Background

Infection surveillance and risk factor analysis are among the most important prerequisites for the prevention and treatment of nosocomial bacteria infections, which are the demands for both infected and non-infected patients.

Purpose

To explore the risk factors for nosocomial bacterial infection of patients with COVID-19, and further to provide a theoretical basis for scientific prevention and control of nosocomial bacterial infection.

Methods

Between 10 January 2020 and 9 March 2020, we collected data of 212 patients with COVID-19 and then explored the influence of age, gender, length of stay, use of ventilator, urinary catheterization, central venous catheterization, white blood cell (WBC) count and procalcitonin on the nosocomial bacterial infection of patients with COVID-19 by a retrospective study.

Results

There were 212 confirmed cases of COVID-19, of which 31 cases had nosocomial bacterial infections, with an incidence of 14.62%. The most common types of nosocomial bacterial infections were lower respiratory tract (12 cases, 38.71%), which was the most frequent site, followed by urinary tract (10 cases, 32.26%), blood stream (7 cases, 22.58%), upper respiratory tract (1 case, 3.23%) and gastrointestinal tract infection (1 case, 3.23%). The incidence of nosocomial bacterial infection was significantly correlated with age, arteriovenous catheterization, urinary catheterization, WBC count and procalcitonin. Moreover, multivariate analysis confirmed that WBC (OR 8.38, 95% CI 1.07 to 65.55), procalcitonin (OR 4.92, 95% CI 1.39 to 17.33) and urinary catheterization (OR 25.38, 95% CI 5.09 to 126.53) were independent risk factors for the nosocomial bacterial infection of patients with COVID-19.

Conclusion

Understanding the risk factors for nosocomial bacterial infection of patients with COVID-19 and strengthening the monitoring of various susceptible factors are helpful to control the occurrence of nosocomial bacterial infection in the COVID-19 isolation wards.

Antibacterial Efficacy and Mechanism of Mannosylerythritol Lipids-A on Listeria monocytogenes

Mannosylerythritol lipids-A (MEL-A) is a novel biosurfactant with excellent surface activity and potential biomedical applications. In this study, we explored the antibacterial activity and the underlying mechanisms of MEL-A against the important food-borne pathogen Listeria monocytogenes. The bacterial growth and survival assays revealed a remarkable antibacterial activity of MEL-A. Since MEL-A is a biosurfactant, we examined the cell membrane integrity and morphological changes of MEL-A-treated bacteria by biochemical assays and flow cytometry analysis and electron microscopes. The results showed obvious damaging effects of MEL-A on the cell membrane and morphology. To further explore the antibacterial mechanism of MEL-A, a transcriptome analysis was performed, which identified 528 differentially expressed genes (DEGs). Gene ontology (GO) analysis revealed that the gene categories of membrane, localization and transport were enriched among the DEGs, and the analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways demonstrated significant changes in the maltodextrin ABC transporter system and stress response system. Furthermore, the growth of L. monocytogenes could also be significantly inhibited by MEL-A in milk, a model of a real food system, suggesting that MEL-A could be potentially applied as an natural antimicrobial agent to control food-borne pathogens in the food industry.

Processing bovine intestinal mucosa to active heparin removes spiked BSE agent

Heparin is an anticoagulant sourced from animal tissues. In the 1990s, bovine-sourced heparin was withdrawn from the U.S. market due to a theoretical concern that the bovine spongiform encephalopathy (BSE) agent might contaminate crude heparin and spread to humans as variant Creutzfeldt-Jakob disease. Only porcine intestinal heparin is now marketed in the U.S. FDA has encouraged the reintroduction of bovine heparin. We applied a scaled-down laboratory model process to produce heparin as an active pharmaceutical ingredient (API) starting from bovine intestinal mucosa. The process consisted of two phases. To model the first phase, we applied enzymatic proteolysis, anionic resin separation and methanol precipitation of crude heparin. Bovine intestinal mucosa was spiked with BSE or scrapie agents. We assayed BSE- or scrapie-associated prion protein (PrP^TSE) using the Real-Time Quaking-Induced Conversion (RT-QuIC) assay at each step. The process reduced PrP^TSE by 4 log₁₀ and 6 log₁₀ from BSE-spiked and scrapie-spiked mucosa, respectively. To model the entire process, we spiked mucosa with scrapie agent and produced heparin API, reducing PrP^TSE by 6.7 log₁₀. The purification processes removed large amounts of PrP^TSE from the final products. Heparin purification together with careful sourcing of raw materials should allow safely reintroducing bovine heparin in the U.S.

Sleep quality and its impacts on quality of life among military personnel in remote frontier areas and extreme cold environments

BACKGROUND

Poor sleep quality negatively affects the readiness of military operations and is also associated with the development of mental health disorders and decreased quality of life. The purpose of this study was to investigate the sleep quality of military personnel from remote boundaries of China and its relationship with coping strategies, anxiety, and health-related quality of life (HRQoL).

METHODS

A cross-sectional survey was performed among military officers and soldiers from a frontier defence department and an extreme cold environment. The participants were surveyed using the Pittsburgh Sleep Quality Index (PSQI), Trait Coping Style Questionnaire (TCSQ), Self-rating Anxiety Scale (SAS), and Short Form Health Survey (SF-36).

RESULTS

A total of 489 military officers and soldiers were included. The participants had a mean age of 22.29 years. The median overall PSQI score was 7.0 (IQR, 4.0 ~ 9.0), with 40.9% (200/489) of the subjects reporting poor sleep quality. The difficulties with sleep were mainly related to daytime dysfunction due to disrupted sleep, sleep latency, and subjective sleep quality. The median score of the SF-36 physical component was 83.5 (IQR, 73.0 ~ 90.5), and the median score of the mental component was 74.1 (IQR, 60.4 ~ 85.1). Significant correlations were found between the PSQI and SF-36 (r = - 0.435, P <  0.01). Anxiety symptoms, marital status, educational background, and global PSQI score were demonstrated as predictors of a low SF-36 physical component by multiple regression analysis (F = 17.06, P <  0.001, R2 = 0.117).

CONCLUSIONS

Sleep difficulty is a prevalent and underestimated problem in the military that negatively influences HRQoL, especially in physical and social functioning. Evaluation of and education on pain were recommended because of body pain and its negative impacts on sleep quality, coping strategies, anxious emotions and HRQoL.

Childhood COVID-19: a multicentre retrospective study

Objectives

To investigate the clinical and epidemiological characteristics of paediatric patients with coronavirus disease-19 (COVID-19).

Methods

Paediatric patients diagnosed with COVID-19 between January 15 and March 15, 2020, from seven hospitals in Zhejiang Province, China, were collected retrospectively and analysed.

Results

Thirty-two children with COVID-19, ranging in age from 3 months to 18 years, were enrolled. Family aggregation occurred in 87.5% of infant and preschool-aged children (7/8), and also school-aged children (14/16), but in only 12.5% (1/8) of adolescents (p < 0.05, p < 0.001). Most of these patients had mild symptoms: mainly fever (20/32) followed by cough (10/32) and fatigue (4/32). The average durations of viral RNA in respiratory samples and gastrointestinal samples were 15.8 d and 28.9 d, respectively. Detox duration in faeces decreased with age: 39.8 d, 27.5 d and 20.4 d in infants and preschool children, school children, and adolescents respectively (p_{0–6, –18} <0.01, p_{0–6, –14} <0.05). Pneumonia was found in 14 children, but there was no statistical significance in the incidence of pneumonia between different age groups. Thirty patients were treated with antiviral drugs, and all patients were stable and gradually improved after admission.

Conclusions

Most children with COVID-19 had a mild process and a good prognosis. More attention should be paid to investigation of household contact history in the diagnosis of COVID-19 in young children. Viral RNA lasts longer in the gastrointestinal system than in the respiratory tract, especially in younger children.

THU0252 CORRELATION BETWEEN DISEASE ACTIVITY AND MENTAL HEALTH IN SLE PATIENTS: A CROSS-SECTION STUDY WITH SELF-ASSESSMENTS BASED ON SMART SYSTEM OF DISEASE MANAGEMENT (SSDM) MOBILE TOOLS

Background:

WHO survey showed that the prevalence of anxiety and depression in Chinese population and Chinese patients with chronic diseases were between 3.1% - 4.2% and 3.1% - 7.3%, respectively. SLEDAI-2K and Hospital Anxiety and Depression Scale (HADS) are commonly used to evaluate SLE patients’ disease activity and mental health. All the Assessments were mainly performed by health professionals (HCPs) with paper questionnaire previously. SSDM is a novel smart disease management tool that allows patients to do self-assessments on SLEDAI-2K and HADS by mobile App.

Objectives:

To investigate the prevalence of anxiety and depression in Chinese patients with SLE and to analyze the potential association between disease activity of SLE and mental health.

Methods:

Under the guidance and training by HCPs, SLE patients downloaded SSDM and performed self-assessments bundle of SLEDAI-2K and HADS with SSDM. SLEDAI-2K <=4, 5-9, 10-14 and >=15 are defined SLE inactive, low (LDA), moderate (MDA) and high (HDA) disease activity, respectively. SLEDAI-2K score <= 4 is set as the main criteria for Lupus Low Disease Activity State (LLDAS) and achievement of T2T. HADS score >=8 can be diagnosed with anxiety or depression.

Results:

From June 2016 to Jan 2020, 3,332 SLE patients (199 male, 3,133 female) with a mean age of 36.34 ± 12.80 (10-91) years and the median disease duration of 3.43 years from 216 hospitals performed bundle self-assessments for 4,967 times in total. According to the HADS and SLEDAI-2K Assessment results, the prevalence of anxiety and depression in all patients was 36.7% and 39.3% respectively, which was significantly higher than that in the WHO survey in Chinese population and chronic disease patients. The proportion of patients achieved and failed on LLDAS was 53% and 47%, respectively. The prevalence of anxiety (A) and depression (D) was 19% and 27% among LLDAS achievers; 41% and 47% among LLDAS failures, respectively (pA<0.01, pD<0.01).

According to SLEDAI-2K, in LLDAS, LDA, MDA and HDA subgroups, the prevalence of anxiety and depression was 19%, 30%, 37%, 54% and 27%, 36%, 44%, 61%, respectively. The correlation coefficients of anxiety (A) and depression (D) with SLEDAI-2K were rA=0.9957 and rD=0.9819. It suggested that with the increase of disease activity, the proportion of SLE patients with anxiety and depression increased significantly. (Figure 1)

Conclusion:

Conclusion: Higher prevalence of anxiety and depression were Associated with higher levels of disease activity in SLE patients. SSDM is an effective mobile interface to monitor and study entanglement of disease activity and mental health in SLE patients, which build a foundation for proactive interventions physically and mentally in future.

References:

Acknowledgments:

SSDM was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

Study of the Spatio-Temporal Differentiation of Factors Influencing Carbon Emission of the Planting Industry in Arid and Vulnerable Areas in Northwest China

Due to the importance of understanding the relationship between agricultural growth and environmental quality, we analyzed how high-quality agricultural development can affect carbon emissions in Northwest China. Based on the concept of the environmental Kuznets curve, this study uses provincial panel data from 1993 to 2017 to make empirical analyses inflection point changes and spatio-temporal differences in agricultural carbon emissions. The highlights of our findings are as follows: (1) In Northwest China, there is an inverse N-shape curve, and the critical values are 3578 yuan/hm2 and 45,738 yuan/hm2, respectively. (2) For 2017, the agricultural economic intensity was 50,670 yuan/hm2, exceeding the critical value (high inflection point) of 45,738 yuan/hm2. (3) Ningxia, Gansu, and Qinghai have not reached the turning point. Having comparable climate, natural conditions, and overall environmental factors, these three provinces would reach the turning point at similar time periods. (4) The average value in agricultural carbon emission intensity in the region is 767.79 kg/hm2, and the order based on intensity is Xinjiang > Shaanxi > Ningxia > Gansu > Qinghai.

Mitochondria-Mediated Programmed Cell Death in Saccharomyces cerevisiae Induced by Betulinic Acid Is Accelerated by the Deletion of PEP4 Gene

In this work, using Saccharomyces cerevisiae as a model, we showed that BetA could inhibit cell proliferation and lead to lethal cytotoxicity accompanying programmed cell death (PCD). Interestingly, it was found that vacuolar protease Pep4p played a pivotal role in BetA-induced S. cerevisiae PCD. The presence of Pep4p reduced the damage of BetA-induced cells. This work implied that BetA may induce cell death of S. cerevisiae through mitochondria-mediated PCD, and the deletion of Pep4 gene possibly accelerated the effect of PCD. The present investigation provided the preliminary research for the complicated mechanism of BetA-induced cell PCD regulated by vacular protease Pep4p and lay the foundation for understanding of the Pep4p protein in an animal model.

Synthesis, Characterization of Liposomes Modified with Biosurfactant MEL-A Loading Betulinic Acid and Its Anticancer Effect in HepG2 Cell

As a novel natural compound delivery system, liposomes are capable of incorporating lipophilic bioactive compounds with enhanced compound solubility, stability and bioavailability, and have been successfully translated into real-time clinical applications. To construct the soy phosphatidylcholine (SPC)-cholesterol (Chol) liposome system, the optimal formulation was investigated as 3:1 of SPC to Chol, 10% mannosylerythritol lipid-A (MEL-A) and 1% betulinic acid. Results show that liposomes with or without betulinic acid or MEL-A are able to inhibit the proliferation of HepG2 cells with a dose-effect relation remarkably. In addition, the modification of MEL-A in liposomes can significantly promote cell apoptosis and strengthen the destruction of mitochondrial membrane potential in HepG2 cells. Liposomes containing MEL-A and betulinic acid have exhibited excellent anticancer activity, which provide factual basis for the development of MEL-A in the anti-cancer applications. These results provide a design thought to develop delivery liposome systems carrying betulinic acid with enhanced functional and pharmaceutical attributes.

Identification of Down-Regulated Proteome in Saccharomyces cerevisiae with the Deletion of Yeast Cathepsin D in Response to Nitrogen Stress

Vacuolar proteinase A (Pep4p) is required for the post-translational precursor maturation of vacuolar proteinases in Saccharomyces cerevisiae, and important for protein turnover after oxidative damage. The presence of proteinase A in brewing yeast leads to the decline of beer foam stability, thus the deletion or inhibition of Pep4p is generally used. However, the influence of Pep4p deletion on cell metabolism in Saccharomyces cerevisiae is still unclear. Herein, we report the identification of differentially down-regulated metabolic proteins in the absence of Pep4p by a comparative proteomics approach. 2D-PAGE (two-dimensional polyacrylamide gel electrophoresis) presented that the number of significantly up-regulated spots (the Pep4p-deficient species versus the wild type) was 183, whereas the down-regulated spots numbered 111. Among them, 35 identified proteins were differentially down-regulated more than 10-fold in the Pep4p-deficient compared to the wild-type species. The data revealed that Pep4p was required for the synthesis and maturation of several glycolytic enzymes and stress proteins, including Eno2p, Fba1p, Pdc1p, Tpi1p, Ssa1, Hsp82p, and Trr1p. The transcription and post-translational modifications of glycolytic enzymes like Eno2p and Fba1p were sensitive to the absence of Pep4p; whereas the depletion of the pep4 gene had a negative impact on mitochondrial and other physiological functions. The finding of this study provides a systematic understanding that Pep4p may serve as a regulating factor for cell physiology and metabolic processes in S. cerevisiae under a nitrogen stress environment.

3.7 kW monolithic narrow linewidth single mode fiber laser through simultaneously suppressing nonlinear effects and mode instability

In this paper, we report a 3.7 kW all fiber narrow linewidth single mode fiber laser. The full width at half-maximum is about 0.30 nm, and the beam quality is Mx2=1.358, My2=1.202 at maximum output power. The laser is achieved by simultaneously suppressing nonlinear effects and mode instability (MI). Different seeds are injected into the main amplifier to study stimulated Raman scattering (SRS) effect. The results show that the phase modulated single frequency seed is benefit to suppress the SRS effect. For the phase modulated single frequency seed, inserting a filter in preamplifier will suppress amplified spontaneous emission (ASE) and decrease the backward power. By optimizing the coiling of active fiber, the MI effect is suppressed.

Preparation, Characterization, and Antibacterial Effects of Chitosan Nanoparticles Embedded with Essential Oils Synthesized in an Ionic Liquid Containing System

Several chitosan sodium tripolyphosphate (TPP) nanoparticles embedded with Torreya grandis aril essential oils (TEOs) were synthesized using an emulsion-ionic gelation technique. Mannosylerythritol lipid A (MEL-A), a type of biosurfactant, was selected as the emulsifier. In order to replace acetic acid, an ionic liquid (IL) was employed to dissolve chitosan. The physical properties, diameters, morphology, embedding rate, and antibacterial effects of those essential oil loaded chitosan (CS) nanoparticles were characterized. The results demonstrated that chitosan nanoparticles can be successfully prepared in an ionic liquid containing system and the diameters for nanoparticles in acetic acid and ionic liquid solutions are 144.1 ± 1.457 and 219.0 ± 4.045 nm. After loading with essential oils, the size increased to 349.6 ± 10.55 and 542.9 ± 16.74 nm, respectively. Antibacterial properties were investigated by the observation of the inhibition zone against S. aureus. The results revealed that TEO loaded nanoparticles synthesized in acid and IL aqueous systems have stronger antibacterial activities than CS nanoparticles.

Long-term effects: Galectin-1 and specific immunotherapy for allergic responses in the intestine

BACKGROUND AND AIMS

Mast cell activation interferes with the effects of allergen-specific immunotherapy (SIT). Galectin-1 (Gal-1) is capable of regulating immune cells' functions. This study tests the hypothesis that administration of Gal-1 promotes and prolongs the efficacy of SIT via suppressing mast cell activation.

METHODS

An intestinal allergy mouse model was developed. The coadministration of SIT and Gal-1 on suppression of the allergic responses, prevention of mast cell activation, and generation of antigen-specific regulatory T cells (Treg) in the intestine was observed in sensitized mice.

RESULTS

The coadministration of Gal-1 and SIT markedly suppressed the allergic responses in the mouse intestine vs the use of either SIT alone or Gal-1 alone. The Gal-1 binds to the IgE/FcɛRI complexes on the surface of mast cells to prevent mast cell activation during SIT. Gal-1 promoted the SIT-generated allergen-specific Tregs in the intestine of sensitized mice. Coadministration of Gal-1 and SIT significantly enhanced the efficacy of immunotherapy in suppressing allergic responses in the intestine, which lasted for at least for 12 months.

CONCLUSIONS

Long-term effects of specific immunotherapy on intestinal allergy can be achieved with Gal-1/SIT therapy by inhibiting mast cell activation and facilitating Treg development.

[The role and significance of digital reconstruction technique in liver segments based on portal vein structure]

Objective: To study the segment of liver according to the large amount of three-dimensional(3D) reconstructive images of normal human livers and the vascular system, and to recognize the basic functional liver unit based on the anatomic features of the intrahepatic portal veins. Methods: The enhanced CT primitive DICOM files of 1 260 normal human livers from different age groups who treated from October 2013 to February 2017 provided by 16 hospitals were analyzed using the computer-aided surgery system.The 3D liver and liver vascular system were reconstructed, and the digital liver 3D model was established.The vascular morphology, anatomical features, and anatomical distributions of intrahepatic portal veins were statistically analyzed. Results: The digital liver model obtained from the 3D reconstruction of CAS displayed clear intrahepatic portal vein vessels of level four.Perform a digital liver segments study based on the analysis of level four vascular distribution areas.As the less anatomical variation of left hepatic portal vein, the liver was classified into four types of liver segmentation mainly based on right hepatic portal vein.Type A was similar to Couinaud or Cho's segmentation, containing 8 segments(537 cases, 42.62%). Type B contained 9 segments as there are three ramifications of right-anterior portal vein(464 cases, 36.82%). The main difference for Type C was the variation of right-posterior portal vein which was sector shape(102 cases, 8.10%). Type D contained the cases with special portal vein variations, which needs three-dimensional simulation to design individualized liver resection plan(157 cases, 12.46%). These results showed that there was no significant difference in liver segmental typing between genders(χ(2)=2.179, P=0.536) and did not reveal any significant difference in liver segmental typing among the different age groups(χ(2)=0.357, P=0.949). Conclusions: The 3D digital liver model can demonstrate the true 3D anatomical structures, and its spatial vascular variations.The observation of anatomic features, distribution areas of intrahepatic portal veins and individualized liver segmentation achieved via digital medical 3D visualization technology is of great value for understand the complexity of liver anatomy and to guide the precise hepatectomy.

Understanding Curli Amyloid-Protein Aggregation by Hydrogen-Deuterium Exchange and Mass Spectrometry

Bacteria within Curli biofilms are protected from environmental pressures (e.g., disinfectants, antibiotics), and this is responsible for intractable infections. Understanding aggregation of the major protein component of Curli, CsgA, may uncover disease-associated amyloidogenesis mechanisms. Here, we report the application of pulsed hydrogen-deuterium exchange and mass spectrometry (HDX-MS) to study CsgA aggregation, thereby obtaining region-specific information. By following time-dependent peptide signal depletion, presumably a result of insoluble fibril formation, we acquired sigmoidal profiles that are specific for regions (region-specific) of the protein. These signal-depletion profiles not only provide an alternative aggregation measurement, but also give insight on soluble species in the aggregation. The HDX data present as bimodal isotopic distributions, one representing a highly disordered species whereas the other a well-structured one. Although the extents of deuterium uptake of the two species remain the same with time, the relative abundance of the lower mass, less-exchanged species increases in a region-specific manner. The same region-specific aggregation properties also pertain to different aggregation conditions. Although CsgA is an intrinsically disordered protein, within the fibril it is thought to consist of five imperfect β-strand repeating units (labeled R1-R5). We found that the exterior repeating units R1 and R5 have higher aggregation propensities than do the interior units R2, R3, and R4. We also employed TEM to obtain complementary information of the well-structured species. The results provide insight on aggregation and a new approach for further application of HDX-MS to unravel aggregation mechanisms of amyloid proteins.

Deamidation Slows Curli Amyloid-Protein Aggregation

Nonenzymatic deamidation of asparagine and glutamine in peptides and proteins is a frequent modification both in vivo and in vitro. The biological effect is not completely understood, but it is often associated with protein degradation and loss of biological function. Here we describe the deamidation of CsgA, the major protein subunit of curli, which are important proteinaceous components of biofilms. CsgA has a high content of Asn and Gln, a feature seen in a few proteins that self-aggregate. We have implemented an approach to monitor deamidation rapidly by following the globally centroid mass shift, providing guidance for studies at the residue level. From the global mass measurement, we identified, using LC-MS/MS, extensive deamidation of several Asn residues and discovered three "Asn-Gly" sites to be the hottest spots for deamidation. The fibrillization of deamidated CsgA was measured using thioflavin T (ThT) fluorescence, circular dichroism (CD), and a previously reported hydrogen-deuterium exchange (HDX) platform. Deamidated proteins exhibit a longer lag phase and lower final ThT fluorescence, strongly suggesting slower and less amyloid fibril formation. CD spectra show that extensively deamidated CsgA remains unstructured and loses its ability to form amyloids. Mass-spectrometry-based HDX also shows that deamidated CsgA aggregates more slowly than wild-type CsgA. Taken together, the results show that deamidation of CsgA slows its fibrillization and disrupts its function, suggesting an opportunity to modulate CsgA fibrillization and affect curli and biofilm formation.

Promoter polymorphisms of the TIM-4 gene are correlated with disease activity in patients with systemic lupus erythematosus

Although the TIM gene family plays important roles in immune responses, little is known about TIM regulation in the development of systemic lupus erythematosus (SLE). This study aimed to investigate the association of two TIM-4 single nucleotide polymorphisms (SNPs) rs6874202 (-1419G>A) and rs62382402 (-1609G>A) with SLE susceptibility in a Chinese Han population. The results showed no significant differences between patients with SLE and control group for rs6874202 and rs62382402 (p = .72, .53 respectively). However, the anti-dsDNA levels in serum from SLE patients with GG genotype of TIM-4 gene at -1419 site were significantly higher than those with GA and AA genotype (p = .0335), and C3 levels of SLE patients with GG and GA genotype were much lower than those with AA genotypes (p = .0187). Moreover, the apoptotic cell levels of SLE patients with AA and GG genotypes were significantly higher than those with GA genotypes in patients with SLE (p = .0393). In addition, the C3 concentration of SLE patients with the GG genotype of TIM-4 gene at -1609 site was found to be significantly higher than those with the GA genotype (p = .0129). The results imply that GG genotype of the TIM-4 gene at -1419 site might be associated with the disease activity of SLE.

[Extracorporeal membrane oxygenation for rescuing 12 children with acute fulminant myocarditis]

Objective: To summarize clinical experience of using extracorporeal membrane oxygenation (ECMO) in rescuing children with acute fulminant myocarditis (AFM). Method: Data of 12 children with acute fulminate myocarditis (6 boys and 6 girls, median age 8.3 (0.6, 13.0) years, median weight 33.1 (6, 61) kg) who were rescued with ECMO in Children's Hospital, Zhejiang University from September 2009 to August 2015 were analyzed retrospectively. The analysis focused on the intervene timing of ECMO for the cardiogenic shock and hypoperfusion caused by heart failure and(or) lethal arrhythmia and the essentials of ECMO cardiopulmonary resuscitation(ECPR) for cardiac arrest in pediatric AFM were summarized. Result: The median ECMO duration was 110(22, 240) h. Ten cases survived and 2 were dead of the total of 12 patients. Six ECPR patients survived and 2 were dead in the total of 8 ECPR patients. The complication of 10 survivors were cannula site bleeding (3 cases), hypernatremia and intracranial hemorrhage (1 case), limping (1 case), hoarse voice (1 case), and cerebral injury (1 case). Conclusion: The key points of improving ECMO rescuing outcome for the AFM children are grasping the ECMO intervene timing and training skilled ECMO team. For ECPR patients, keeping effective chest compressions resuscitation is the key to achieve survival and improve the quality of life.