Hydroxycinnamaldehyde-derived benzofuran components in lignins

Lignin is an abundant polymer in plant secondary cell walls. Prototypical lignins derive from the polymerization of monolignols (hydroxycinnamyl alcohols), mainly coniferyl and sinapyl alcohol, via combinatorial radical coupling reactions and primarily via the endwise coupling of a monomer with the phenolic end of the growing polymer. Hydroxycinnamaldehyde units have long been recognized as minor components of lignins. In plants deficient in cinnamyl alcohol dehydrogenase, the last enzyme in the monolignol biosynthesis pathway that reduces hydroxycinnamaldehydes to monolignols, chain-incorporated aldehyde unit levels are elevated. The nature and relative levels of aldehyde components in lignins can be determined from their distinct and dispersed correlations in 2D 1H-13C-correlated nuclear magnetic resonance (NMR) spectra. We recently became aware of aldehyde NMR peaks, well resolved from others, that had been overlooked. NMR of isolated low-molecular-weight oligomers from biomimetic radical coupling reactions involving coniferaldehyde revealed that the correlation peaks belonged to hydroxycinnamaldehyde-derived benzofuran moieties. Coniferaldehyde 8-5-coupling initially produces the expected phenylcoumaran structures, but the derived phenolic radicals undergo preferential disproportionation rather than radical coupling to extend the growing polymer. As a result, the hydroxycinnamaldehyde-derived phenylcoumaran units are difficult to detect in lignins, but the benzofurans are now readily observed by their distinct and dispersed correlations in the aldehyde region of NMR spectra from any lignin or monolignol dehydrogenation polymer. Hydroxycinnamaldehydes that are coupled to coniferaldehyde can be distinguished from those coupled with a generic guaiacyl end-unit. These benzofuran peaks may now be annotated and reported and their structural ramifications further studied.

CRISPR/Cas9 mutated p-coumaroyl shikimate 3'-hydroxylase 3 gene in Populus tomentosa reveals lignin functioning on supporting tree upright

The lignin plays one of the most important roles in plant secondary metabolism. However, it is still unclear how lignin can contribute to the impressive height of wood growth. In this study, C3'H, a rate-limiting enzyme of the lignin pathway, was used as the target gene. C3'H3 was knocked out by CRISPR/Cas9 in Populus tomentosa. Compared with wild-type popular trees, c3'h3 mutants exhibited dwarf phenotypes, collapsed xylem vessels, weakened phloem thickening, decreased hydraulic conductivity and photosynthetic efficiency, and reduced auxin content, except for reduced total lignin content and significantly increased H-subunit lignin. In the c3'h3 mutant, the flavonoid biosynthesis genes CHS, CHI, F3H, DFR, ANR, and LAR were upregulated, and flavonoid metabolite accumulations were detected, indicating that decreasing the lignin biosynthesis pathway enhanced flavonoid metabolic flux. Furthermore, flavonoid metabolites, such as naringenin and hesperetin, were largely increased, while higher hesperetin content suppressed plant cell division. Thus, studying the c3'h3 mutant allows us to deduce that lignin deficiency suppresses tree growth and leads to the dwarf phenotype due to collapsed xylem and thickened phloem, limiting material exchanges and transport.

[Spatial autocorrelation and related factors of stroke mortality in Zhejiang Province based on spatial panel model in 2015-2020]

Objective: To explore the spatial autocorrelation and macro influencing factors of stroke mortality in Zhejiang Province in 2015-2020 and provide a scientific basis for stroke prevention and control strategy. Methods: The data on stroke death were obtained from Zhejiang Chronic Disease Surveillance System. The spatial distribution of stroke mortality was explored by mapping and spatial autocorrelation analysis. The spatial panel model analyzed the correlation between stroke mortality and socioeconomic and healthcare factors. Results: From 2015 to 2020, the average stroke mortality was 68.38/100 thousand. The standard mortality of stroke was high in the areas of east and low in the west, high in the south and low in the north. Moreover, positive spatial autocorrelation was observed (Moran's I=0.274-0.390, P<0.001). Standard mortality of stroke was negatively associated with per capita gross domestic product (GDP) (β=-0.370, P<0.001), per capita health expenditure (β=-0.116, P=0.021), number of beds per thousand population (β=-0.161, P=0.030). Standard mortality of ischemic stroke was negatively associated with per capita GDP (β=-0.310, P=0.002) and standard management rate of hypertension (β=-0.462, P=0.011). Standard mortality of hemorrhagic stroke was negatively associated with per capita GDP (β=-0.481, P<0.001), per capita health expenditure (β=-0.184, P=0.001), number of beds per thousand population (β=-0.288, P=0.001) and standard management rate of hypertension (β=-0.336, P=0.029). Conclusions: A positive spatial correlation existed between stroke mortality in Zhejiang Province in 2015-2020. We must focus more on preventing and controlling strokes in relatively backward economic areas. Moreover, to reduce the mortality of stroke, increasing the investment of government medical and health funds, optimizing the allocation of medical resources, and improving the standard management rate of hypertension are important measures.

[Analysis of big data characteristics of allergic rhinitis patients in Beijing City from 2016 to 2021]

To explore the characteristics of big data of patients with allergic rhinitis, including the time, population and spatial distribution of allergic rhinitis in Beijing from 2016 to 2021, so as to provide reference for the prevention and treatment of this disease. Descriptive epidemiological methods were used to analyze the distribution (including gender, age and location)and trend of allergic rhinitis patients in 30 pilot hospitals from January 2016 to December 2021, T test and Kruskal-Wallis rank sum test were used to test the statistical differences. The results showed that the number of patients with allergic rhinitis in 30 hospitals increased year by year from 2016 to 2019, with an increase of 97.9%. In 2020, the number of patients decreased. In 2021, the number of visits returned to the pre-epidemic level (461 332); The number of patients with allergic rhinitis was the highest in September, with a seasonal index of 177.6%, while the lowest number was in February, accounting for only 47.2%; a significant difference was observed in the number of patients in different age groups(H=45 319.48, P<0.05), and patients under 15 years old accounted for the highest proportion(819 284 visits); There were significant differences between patients of different genders in the 45-59 year old group (t=-4.26, P<0.05).There were relatively more patients with allergic rhinitis in Dongcheng District(31.1%) than in Huairou District and Miyun District (0.4%). In conclusion, since 2016, the number of patients increased significantly, with a varied trend in different seasons. Most patients were children. There were more patients in the central urban area than in the outer suburbs.

Overexpression of a gibberellin 20-oxidase gene in poplar xylem led to an increase in the size of nanocellulose fibrils and improved paper properties

Cellulose, the major component of secondary cell walls, is the most abundant renewable long-chain polymer on earth. Nanocellulose has become a prominent nano-reinforcement agent for polymer matrices in various industries. We report the generation of transgenic hybrid poplar overexpressing the Arabidopsis gibberellin 20-oxidase1 gene driven by a xylem-specific promoter to increase gibberellin (GA) biosynthesis in wood. X-ray diffraction (XRD) and sum frequency generation spectroscopic (SFG) analyses showed that cellulose in transgenic trees was less crystalline, but the crystal size was larger. The nanocellulose fibrils prepared from transgenic wood had an increased size compared to those from wild type. When such fibrils were used as a reinforcing agent in sheet paper preparation, the mechanical strength of the paper was significantly enhanced. Engineering the GA pathway can therefore affect nanocellulose properties, providing a new strategy for expanding nanocellulose applications.

Randomized phase II adjuvant trial to compare two treatment durations of icotinib (2 years versus 1 year) for stage II-IIIA EGFR-positive lung adenocarcinoma patients (ICOMPARE study)

BACKGROUND

Despite the prolonged median disease-free survival (DFS) by adjuvant targeted therapy in non-small-cell lung cancer patients with epidermal growth factor receptor (EGFR) mutations, the relationship between the treatment duration and the survival benefits in patients remains unknown.

PATIENTS AND METHODS

In this multicenter, randomized, open-label, phase II trial, eligible patients aged 18-75 years with EGFR-mutant, stage II-IIIA lung adenocarcinoma and who had not received adjuvant chemotherapy after complete tumor resection were enrolled from eight centers in China. Patients were randomly assigned (1 : 1) to receive either 1-year or 2-year icotinib (125 mg thrice daily). The primary endpoint was DFS assessed by investigator. The secondary endpoints were overall survival (OS) and safety. This study was registered at ClinicalTrials.gov (NCT01929200).

RESULTS

Between September 2013 and October 2018, 109 patients were enrolled (1-year group, n = 55; 2-year group, n = 54). Median DFS was 48.9 months [95% confidence interval (CI) 33.1-70.1 months] in the 2-year group and 32.9 months (95% CI 26.6-44.8 months) in the 1-year group [hazard ratio (HR) 0.51; 95% CI 0.28-0.94; P = 0.0290]. Median OS for patients was 75.8 months [95% CI 64.4 months-not evaluable (NE)] in the 2-year group and NE (95% CI 66.3 months-NE) in the 1-year group (HR 0.34; 95% CI 0.13-0.95; P = 0.0317). Treatment-related adverse events (TRAEs) were observed in 41 of 55 (75%) patients in the 1-year group and in 36 of 54 (67%) patients in the 2-year group. Grade 3-4 TRAEs occurred in 4 of 55 (7%) patients in the 1-year group and in 3 of 54 (6%) patients in the 2-year group. No treatment-related deaths or interstitial lung disease was reported.

CONCLUSIONS

Two-year adjuvant icotinib was shown to significantly improve DFS and provide an OS benefit in EGFR-mutant, stage II-IIIA lung adenocarcinoma patients compared with 1-year treatment in this exploratory phase II study.

Lignin Hydrogenolysis: Phenolic Monomers from Lignin and Associated Phenolates across Plant Clades

The chemical complexity of lignin remains a major challenge for lignin valorization into commodity and fine chemicals. A knowledge of the lignin features that favor its valorization and which plants produce such lignins can be used in plant selection or to engineer them to produce lignins that are more ideally suited for conversion. Sixteen biomass samples were compositionally surveyed by NMR and analytical degradative methods, and the yields of phenolic monomers following hydrogenolytic depolymerization were assessed to elucidate the key determinants controlling the depolymerization. Hardwoods, including those incorporating monolignol p-hydroxybenzoates into their syringyl/guaiacyl copolymeric lignins, produced high monomer yields by hydrogenolysis, whereas grasses incorporating monolignol p-coumarates and ferulates gave lower yields, on a lignin basis. Softwoods, with their more condensed guaiacyl lignins, gave the lowest yields. Lignins with a high syringyl unit content released elevated monomer levels, with a high-syringyl polar transgenic being particularly striking. Herein, we distinguish phenolic monomers resulting from the core lignin vs those from pendent phenolate esters associated with the biomass cell wall, acylating either polysaccharides or lignins. The basis for these observations is rationalized as a means to select or engineer biomass for optimal conversion to worthy phenolic monomers.

[Prevalence and influencing factors of human soil-transmitted nematode infections in Ningbo City from 2016 to 2021]

OBJECTIVE

To investigate the prevalence and influencing factors of soil-transmitted nematode infections in Ningbo City from 2016 to 2021, so as to provide insights into the development of targeted control measures against soil-transmitted nematodiasis.

METHODS

Permanent residents at ages of 3 years and older were sampled in Ningbo City using a multi-stage sampling method each year during the period from 2016 to 2021. Soil-transmitted nematode eggs were detected in stool samples using a modified Kato-Katz thick smear method (two slides for each stool sample), and Enterobius vermicularis eggs were additionally identified among children at ages of 3 to 12 years using the adhesive cellophane-tape perianal swab method. The time- and regions-specific prevalence of soil-transmitted nematode infections was calculated, and the factors affecting hookworm infections were identified using a multivariate logistic regression model.

RESULTS

A total of 11 573 person-times were detected for soil-transmitted nematode infections in Ningbo City from 2016 to 2021, and 296 egg-positives were detected, with a mean prevalence rate of 2.56% [95% confidential interval (CI): (2.28%, 2.87%)]. Hookworm was the predominant species of soil-transmitted nematode among egg-positives in Ningbo City (98.31%, 291/296), and there was a significant difference in the prevalence of hook-worm infections among years (χ² = 190.27, P < 0.01). The highest prevalence of hook-worm infections was observed in Ninghai County (4.06%), and there was a region-specific prevalence rate of hookworm infection in Ningbo City (χ² = 148.43, P < 0.01). Multivariate logistic regression analysis showed that elderly residents at ages of over 60 years [odds ratio (OR)= 1.94, 95% CI: (1.07, 3.54), P < 0.05], males [OR = 2.19, 95% CI: (1.72, 2.80), P < 0.01], farmers [OR = 6.94, 95% CI: (3.37, 14.29), P < 0.01] and residents with a low education level [illiteracy or semi-illiterate: OR = 3.82, 95% CI: (1.56, 9.35), P < 0.05; primary school: OR = 2.70, 95% CI: (1.11, 6.59), P < 0.05] were at a higher risk for hookworm infections.

CONCLUSIONS

The overall prevalence of soil-transmitted nematode infections was low among residents in Ningbo City from 2016 to 2021. The surveillance and health education for human hookworm disease remain to be reinforced among male farmers with a low education level at ages of over 60 years in Ninghai County.

The impact of the metabolic score for insulin resistance on cardiovascular disease: a 10-year follow-up cohort study

PURPOSE

To investigate whether the metabolic score for insulin resistance (METS-IR) is associated with an increased risk of cardiovascular disease (CVD).

METHODS

A total of 6489 participants aged 35-70 years without a history of CVD were included in this prospective cohort study. The median follow-up time was 10.6 years. The METS-IR was calculated as ln [2 × FPG (mg/dL) + fasting TG (mg/dL)] × BMI (kg/m²)/ln [HDL-C (mg/dL)]. The primary outcome was CVD, defined as the composite of coronary heart disease (CHD) and stroke.

RESULTS

During follow-up, 396 individuals developed CVD. Kaplan-Meier survival curves by quintiles of METS-IR showed statistically significant differences (log-rank test, P < 0.001). Multivariate Cox regression analysis showed that the hazard ratio [95% confidence interval (95% CI)] of CVD was 1.80 (1.24-2.61) in quintile 5 and 1.17 (1.05-1.31) for per standard deviation (SD) increase in METS-IR. In subgroup analysis, the significant association between METS-IR and CVD was mainly observed among females and subjects without diabetes mellitus. A significant interaction was found between gender and METS-IR (P-interaction = 0.001). Moreover, adding METS-IR to models with traditional risk factors yielded a significant improvement in discrimination and reclassification of incident CVD.

CONCLUSION

The elevated METS-IR was independently associated with incident CVD, suggesting that the METS-IR might be a valuable indicator for risk stratification and early intervention of CVD.

Nanolignin-based high internal phase emulsions for efficient protection of curcumin against UV degradation

As an emulsifier, lignin exhibits excellent UV resistance on drug-loaded emulsion systems for drug delivery. However, due to the structural variation and complexity of lignins from various origins, their UV shielding performance varies with the techniques for lignin extraction, which impacts properties and the protection efficiency of lignin-based HIPEs (high internal phase emulsions). In this work, lignin nanoparticles, prepared from three lignin preparations of Eucalyptus, were used in HIPEs delivery systems to protect curcumin from degradation by UV radiation. Structures of the lignin preparations were characterized using 2D HSQC (heteronuclear single-quantum coherence) NMR (nuclear magnetic resonance), ³¹P NMR, and GPC (gel permeation chromatography). The residual curcumin level after 36 h UV exposure in the nanolignin-based HIPEs was over 72 %, much higher than that (< 10 % after 24 h UV exposure) in the oil phase without lignin, indicating that the nanolignin-based HIPEs with enhanced UV shielding ability protect curcumin better. Of the three lignin preparations, AL (alkali lignin), with the lowest molecular weight, highest contents of phenolic hydroxyl and carboxyl groups, and highest S/G ratio, displayed the best anti-UV radiation ability and the most uniform nanoparticle size.

The role of mitochondrial fission in intervertebral disc degeneration

Low back pain (LBP) is an extremely common disorder and is a major cause of disability globally. Intervertebral disc degeneration (IVDD) is the main contributor to LBP. Nevertheless, the specific mechanisms underlying the pathogenesis of IVDD remain unclear. Mitochondria are highly dynamic organelles that continuously undergo fusion and fission, known as mitochondrial dynamics. Accumulating evidence has revealed that aberrantly activated mitochondrial fission leads to mitochondrial fragmentation and dysfunction, which are involved in the development and progression of IVDD. To date, research into mitochondrial dynamics in IVDD is at an early stage. The present narrative review aims to summarize the most recent findings about the role of mitochondrial fission in the pathogenesis of IVDD.

[Progress on the mechanism and application of adipose-derived stem cells in promoting wound repair]

Chronic refractory wounds and scars caused by abnormal wound repair seriously damage the health of patients and affect their quality of life. At present, there is a lack of simple but effective and economical treatment methods. Adipose-derived stem cells (ASCs), as a kind of mesenchymal stem cells with multi-directional differentiation potential, have been confirmed by several in vivo and in vitro studies to promote wound healing by promoting epithelialization, angiogenesis, immunoregulation, antioxidant properties, and other mechanisms. ASCs and their derivatives have been used in the treatment of refractory wounds caused by burns, diabetic, and radiation injuries with good results achieved. Their potential to become new materials for wound repair has also been confirmed. This paper reviewed the mechanism and clinical application of ASCs in promoting wound repair, and looked into its research direction and prospects.

The clinical value of high mobility group box-1 and CRP/Alb ratio in the diagnosis and evaluation of sepsis in children

OBJECTIVE

To explore the clinical value of high mobility group box-1 (HMGB-1), C-reactive protein (CRP), procalcitonin (PCT), and CRP to albumin (Alb) ratio in the diagnosis and evaluation of the severity of sepsis in children.

PATIENTS AND METHODS

A total of 90 children, 50 with sepsis and 40 with general infection, whose symptoms did not meet the criteria for diagnosis of sepsis, were admitted to the Pediatrics Department of Jingzhou Central Hospital in Hubei Province between November 2021 and December 2022, were enrolled and selected as experimental and control group, respectively. The serum of two groups was collected within 24 hours after admission, the levels of HMGB-1 were detected by enzyme-linked immunosorbent assay (ELISA), and CRP, PCT, Alb, and hospitalization days were recorded. The differences in indicators between the two groups were compared, and correlation analysis was performed between hospitalization days and various indicators. The receiver operating characteristic (ROC) curve was drawn to evaluate the independent or combined value of CRP, PCT, HMGB-1, and CRP/Alb ratio in the early diagnosis of sepsis in children.

RESULTS

These four indicators of children with sepsis were significantly higher than those in the general infection group (all p=0.000). The levels of CRP, PCT and CRP/Alb ratio were significantly positively correlated with the hospitalization days (r=0.329, 0.333, 0.329; p=0.02, 0.01, 0.002). The area under curve (AUC) of CRP, PCT, HMGB-1, and CRP/Alb ratio for the diagnosis of sepsis in children was 0.798, 0.817, 0.838, 0.809, respectively, and that of the combination of four indicators was 0.952.

CONCLUSIONS

CRP, PCT, HMGB-1, and CRP/Alb ratio resulted as effective indicators for early diagnosis and evaluation of childhood sepsis, having a higher value in combined diagnosis.

Manipulation of Lignin Monomer Composition Combined with the Introduction of Monolignol Conjugate Biosynthesis Leads to Synergistic Changes in Lignin Structure

The complexity of lignin structure impedes efficient cell wall digestibility. Native lignin is composed of a mixture of three dominant monomers, coupled together through a variety of linkages. Work over the past few decades has demonstrated that lignin composition can be altered through a variety of mutational and transgenic approaches such that the polymer is derived almost entirely from a single monomer. In this study, we investigated changes to lignin structure and digestibility in Arabidopsis thaliana in near-single-monolignol transgenics and mutants and determined whether novel monolignol conjugates, produced by a FERULOYL-CoA MONOLIGNOL TRANSFERASE (FMT) or a p-COUMAROYL-CoA MONOLIGNOL TRANSFERASE (PMT), could be integrated into these novel polymers to further improve saccharification efficiency. Monolignol conjugates, including a new conjugate of interest, p-coumaryl p-coumarate, were successfully integrated into high-H, high-G and high-S lignins in A. thaliana. Regardless of lignin composition, FMT- and PMT-expressing plants produced monolignol ferulates and monolignol p-coumarates, respectively, and incorporated them into their lignin. Through the production and incorporation of monolignol conjugates into near-single-monolignol lignins, we demonstrated that substrate availability, rather than monolignol transferase substrate preference, is the most important determining factor in the production of monolignol conjugates, and lignin composition helps dictate cell wall digestibility.

The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence

To date, little is known about the evolution of fern genomes, with only two small genomes published from the heterosporous Salviniales. Here we assembled the genome of Alsophila spinulosa, known as the flying spider-monkey tree fern, onto 69 pseudochromosomes. The remarkable preservation of synteny, despite resulting from an ancient whole-genome duplication over 100 million years ago, is unprecedented in plants and probably speaks to the uniqueness of tree ferns. Our detailed investigations into stem anatomy and lignin biosynthesis shed new light on the evolution of stem formation in tree ferns. We identified a phenolic compound, alsophilin, that is abundant in xylem, and we provided the molecular basis for its biosynthesis. Finally, analysis of demographic history revealed two genetic bottlenecks, resulting in rapid demographic declines of A. spinulosa. The A. spinulosa genome fills a crucial gap in the plant genomic landscape and helps elucidate many unique aspects of tree fern biology.

Isolation, Characterization, and Depolymerization of l-Cysteine Substituted Eucalyptus Lignin

Lignin condensation reactions are hard to avoid or control during separation, which is a deterrent to lignin isolation and post-conversation, especially for the full utilization of lignocelluloses. Selective protection of β-aryl ether linkages in the isolation process is crucial to lignin valorization. Herein, a two-step acid/alkali separation method assisted with l-cysteine for eucalyptus lignin separation is developed, and the isolated l-cysteine lignins (LCLs) are comprehensively characterized by 2D NMR, ³¹P NMR, thioacidolysis, etc. Compared to the two-step control treatment, a much higher β-O-4 content is preserved without reducing the separation efficiency assisted by l-cysteine, which is also significantly higher than alkali lignin and kraft lignin. The results of hydrogenolysis show that LCLs generate a much higher monomer yield than that of control sample. Structural analysis of LCLs suggests that lignin condensation reaction, to some extent, is suppressed by adding l-cysteine during the two-step acid/alkali separation. Further, mechanistic studies using dimeric model compound reveals that l-cysteine may be the α-carbon protective agent in the two-step separation. The role of l-cysteine in the two-step lignin isolation method provides novel insights to the selective fractionation of lignin from biomass, especially for the full valorization of lignocellulosic biomass.

[Factors associated with identification of lymph node detected by axillary reverse mapping for breast cancer]

Objective: To investigate the different tracer materials in identifying the axillary reverse mapping(ARM) lymph nodes. Methods: A retrospective analysis of clinical and pathological data of 478 breast cancer female patients(mean age: 50.5±8.0) under axillary lymph node dissection(ALND) with ARM technique was conducted between March 2019 and November 2020 in Wuhan University Zhongnan Hospital. Of the 478 patients, methylene blue was applied in 147 patients, indocyanine green in 119, and indocyanine green plus methylene blue in 212 patients. Wilcoxon rank-sum test, Chi-squire test or Fisher test, and binary logistic regression were carried out to identify the factors associated with identifying ARM lymph nodes. Results: The recognition rates of ARM lymph nodes were 73.5%, 79.0%, and 83.0%(P=0.091), and the recognition rate of ARM lymphatic vessels was 62.6%, 92.4%, 89.6%(P<0.001), respectively. The coincidence rate of ARM lymph node and SLN was 8.1%(12/148), and the metastasis rate was 16.1%(61/378). Supplemental injection of 1 ml of methylene blue or indocyanine green can improve the identification of ARM lymph nodes. The larger BMI and the performance of neoadjuvant therapy were associated with the lower recognition rate of ARM lymph nodes. Neoadjuvant therapy was an independent factor for the identification rate of ARM lymph nodes. Conclusions: Indocyanine green combined with methylene blue can improve the recognition rate of ARM lymph nodes. Obese patients have a lower recognition rate of ARM lymph nodes, and the supplemental injection tracer can be injected to improve the recognition rate. In breast cancer patients whose ARM lymph nodes are not successfully identified during operation, it may be that the ARM lymph nodes are not located in the axilla.

Revascularisation versus apexification for treatment of immature teeth based on periapical healing and root development: A systematic review and meta-analysis

AIM

Immature necrotic teeth are frequent findings in adolescents that may lead to thin root walls and open apexes. The absence of an apical stop becomes a challenge for endodontic treatment because it is difficult or impossible to seal the immature root canal with conventional endodontic techniques. Revascularisation therapy (RET) may be more suitable for the treatment of immature necrotic teeth. However, clinicians are still more inclined to choose apexification (AP) when considering the predictability of treatment results.

METHODS

The literature was searched via PubMed/MEDLINE and the Cochrane Library, Web of Science data from June, 2001 to September, 2020 and randomised clinical trials were selected that compared RET with AP for the treatment of immature necrotic teeth assessing clinical and radiographic results.

RESULTS

A total of 556 articles were retrieved, though only five studies were included. There were no differences in the periapical healing rate, overall effective rate/invalid rate, or apical closure rate between RET and AP. The root length was significantly increased in the RET group compared with the AP group quantitatively (pooled difference in means=1.28, 95% CI: [1.08, 1.48], Z=12.69, P<0.00001) and qualitatively (pooled RR=4.12, 95% CI: [2.44, 6.97]), Z=5.28, P<0.00001). The effective rate of root thickness was significantly increased in the RET group compared with the AP group (pooled RR=22.63, 95% CI: [6.08, 84.26]), Z=4.65, P<0.00001).

CONCLUSIONS

Both RET and AP were effective options regarding the healing of periapical periodontitis or the closure of open apices. Pulp revascularisation is more effective for root elongation and thickening without higher risk of overall invalid treatment.

Corrigendum: BEL1-like Homeodomain Protein BLH6a Is a Negative Regulator of CAld5H2 in Sinapyl Alcohol Monolignol Biosynthesis in Poplar

[This corrects the article DOI: 10.3389/fpls.2021.695223.].

P–392 Clinical outcomes of endometrium receptivity analysis(ERA) testing in patients with repeated IVF failures

Study question

Is ERA testing different between RIF patients with control group?

Summary answer

In RIF patients, there were more chances of non-receptive endometrium. ERA testing may be helpful for the patients with repeated IVF failure. What is known already: The endometrium receptivity analysis testing might have the ability to detect the implantation window. In repeat implantation failure patients, detecting of precisely implantation window may have some benefits.

Study design, size, duration

This was a single-center retrospective observational study. Two hundred and forty-nine patients who underwent ERA testing following frozen-thawed embryo transfer in our center were including in this study between January 2019 and May 2020.

Participants/materials, setting, methods

181 patients having unexplained repeated IVF failure (RIF group, at least tow implantation failure) and 68 patients having no experience with embryo transfer (Control group) who underwent ERA testing were including in this study. Both of Patients having a receptive (R) ERA and having a non-receptive (NR) ERA underwent a personalized embryo transfer (pET) on ERA. ERA results and clinical outcomes compared between RIF group and control group were analyzed by Chi-square test.

Main results and the role of chance

The proportion of R/NR results were 33:35 for the RIF group and 118:63 for the Control group, demonstrating the displacement of the window of implantation in patients with RIF. Our results revealed an endometrial factor in 51% RIF patients, which was significantly greater than the Control group 34.8% (P = 0.02). Among the patients with NR ERA result, there are not significantly difference in clinical pregnancy rate in the RIF group compared with control group (57.1%. vs. 61.9%). The clinical pregnancy rate of the patients with receptive ERA result also is comparable in both group (70.3% vs. 66.7%).

Limitations, reasons for caution

This is a retrospective, single center study with limited case number. There were may some bias with ERA testing errors.

Wider implications of the findings: In RIF patients, there were more chances of non-receptive endometrium. ERA testing may be helpful for the patients with repeated IVF failure. Larger randomized studies are required to validate these results.

Trial registration number

18MMHISO70e

Curcumin improves experimentally induced colitis in mice by regulating follicular helper T cells and follicular regulatory T cells by inhibiting interleukin-21

To determine whether curcumin (Cur) can treat mice with experimentally-induced colitis by regulating follicular helper T cells (Tfh) and follicular regulatory T cells (Tfr) by inhibiting interleukin (IL)-21. In this study, 40 male C57BL/6 mice were randomly grouped into four groups, i.e., normal, trinitrobenzene sulfonic acid (TNBS), TNBS + curcumin, and TNBS + anti-IL-21. Mice with experimental colitis were induced by 100 mg/kg TNBS. The mice in the TNBS + Cur group were treated with 100 mg/kg curcumin for seven days, and mice in the TNBS + anti-IL-21 group were treated with anti-IL-21 (150 μg/mouse) once per week, intraperitoneally, starting on the second day after establishing the experimental colitis model. On day eight, the therapeutic effect of curcumin was evaluated by colon mucosa damage index (CMDI), histological examination, and disease activity index (DAI). Furthermore, the number of CD4 + CXCR5 + PD-1 + Tfh and CD4 + CXCR5 + FoxP3 + Tfr cells were measured by flow cytometry. The mRNA and protein expression of IL-21, Bcl-6, FOXP3, ICOS, and PD-1 in colonic mucosa was detected by reverse transcription polymerase chain reaction and the Western blot technique. Compared with the TNBS group, the DAI, CMDI, histological score, the number of CD4 + CXCR5 + PD-1 + Tfh cells, the expression of IL-21, Bcl-6, ICOS, and PD-1 were significantly decreased in the TNBS + curcumin group and TNBS + anti-IL-21 group; body weight, number of CD4 + CXCR5 + FoxP3 + Tfr cells, and the expression of FoxP3 were observably elevated in the TNBS + curcumin group (all P < 0.05). Curcumin may have a potential therapeutic effect on mice with colitis treated experimentally through regulation of the balance of Tfh and Tfr cells via inhibiting the synthesis of IL-21.

BEL1-like Homeodomain Protein BLH6a Is a Negative Regulator of CAl5H2 in Sinapyl Alcohol Monolignol Biosynthesis in Poplar

Lignin is one of the major components of xylem cell walls in tree stems. The lignin in the wood of most flowering plants (dicotyledonous angiosperms) is typically polymerized from three monolignol precursors, coniferyl alcohol, sinapyl alcohol, and p-coumaroyl alcohol, resulting in guaiacyl (G), syringyl (S), and hydroxyphenyl (H) subunits, respectively. In this study, we focus on the transcriptional regulation of a coniferaldehyde 5-hydroxylase (CAld5H2) gene, which encodes a key enzyme for sinapyl alcohol biosynthesis. We carried out a yeast one-hybrid (Y1H) screen to identify candidate upstream transcription factors (TFs) regulating CAld5H2. We obtained 12 upstream TFs as potential regulators of CAld5H2. One of these TF genes, BLH6a, encodes a BEL1-like homeodomain (BLH) protein and negatively regulated the CAld5H2 promoter activity. The direct regulation of CAld5H2 promoter by BLH6a was supported by chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR) and dominant repression of BLH6a in transgenic plants. Luciferase complementation imaging analyses showed extensive protein-protein interactions among these 12 TFs. We propose that BLH6a is a negative regulator of CAld5H2, which acts through combinatorial regulation of multiple TFs for sinapyl alcohol (S monolignol) biosynthesis in poplar.

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

Background:

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

Objectives:

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

Methods:

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

Results:

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

Table 1.

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

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

Conclusion:

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

References:

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

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

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

Acknowledgements:

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

Disclosure of Interests:

None declared

[A cohort study on plasma uric acid levels and the risk of type 2 diabetes mellitus among the oldest old in longevity areas of China]

Objective: To investigate the effect of plasma uric acid level on the incident risk of type 2 diabetes mellitus (T2DM) among the oldest old (those aged ≥80 years). Methods: Participants were recruited from the Healthy Aging and Biomarkers Cohort Study (HABCS), which conducted a baseline survey in 2008-2009 and follow-up of 3 times in 2011-2012, 2014, and 2017-2018, respectively. A total of 2 213 oldest old were enrolled in this study. The general demographic, socioeconomic, lifestyle and disease data of the oldest old were collected, and physical measurements were made for the oldest old. Fasting venous blood was collected for uric acid and blood glucose detection. Information on the incident and death of T2DM were collected through the follow-up. Cox proportional hazard regression model was used to explore the association of hyperuricemia and plasma uric acid level with the incidence of T2DM. Restricted cubic spline (RCS) function was used to explore the dose-response relationship of plasma uric acid levels with the risk of T2DM. Results: The age of participants was (93.2±7.6) years old, and 66.7% of the participants (1 475) were female. The plasma uric acid level at baseline was (289.1±88.0)μmol/L, and the prevalence of hyperuricemia was 13.3% (294 cases). During 9 years of cumulative follow-up of 7 471 person-years (average of 3.38 years for each), 122 new cases of T2DM occurred and the incidence density was 1 632.98/10⁵ person year. Cox proportional hazards regression analysis showed that per 10μmol/L increase in plasma uric acid level, the risk of T2DM increased by 1.1% [HR (95%CI): 1.011 (1.004, 1.017)]. Compared with the participants with the lowest quintile of plasma uric acid (Q₁), the risk of diabetes increased by 20.7 % among the oldest old with uric acid in the highest quintile (Q₅) [HR (95%CI):1.207 (1.029, 1.416)]. The risk of T2DM was 19.2% higher in the hyperuricemia group than that in the oldest old with normal plasma uric acid [HR (95%CI): 1.192 (1.033, 1.377)]. RCS function showed that the risk of T2DM increased with the increase in plasma uric acid levels in a nonlinear dose-response relationship (P=0.016). Conclusion: The incident risk of T2DM increases with the elevates of plasma uric acid levels in the oldest old.

Target antifungal peptides of immune signalling pathways in silkworm, Bombyx mori, against Beauveria bassiana

Antifungal innate immunity is an important defence used by insects against entomogenous fungi. However, the downstream target antifungal peptides of different immune signalling pathways are unknown. We found that the Toll, Janus kinase/signal transducer and activator of transcription (Jak/STAT) and Immunodeficiency (IMD) signalling pathways in the silkworm, Bombyx mori, can be activated by Beauveria bassiana. Inhibition of the Toll, IMD and Jak/STAT signalling pathways reduced the antifungal activities of silkworm haemolymph. We verified the target antifungal peptides of different immune signalling pathways. The expression patterns of five anti-fungal peptide genes in silkworm larvae and BmN cells were detected after blocking or over-expressing the immune signalling pathways. The Toll signalling pathways mediated the expression of Bmcecropin A, Bmattacin 1 and Bmgloverin 2; IMD signalling pathways mediated Bmenbocin 1, Bmgloverin 2 and Bmattacin 1; Jak/STAT signalling pathways mediated Bmstorage protein 30K-19G1 (Bmsp 1), Bmattacin 1 and Bmcecropin A. These data indicated that anti-microbial peptide genes in B. mori evolved through expansion and selection of existing genes to adapt to the challenge of invasive microorganisms such as fungi. This information provides insight into the antifungal immune responses in B. mori and aids understanding of insect immune regulation mechanisms.

Near real-time surveillance of the SARS-CoV-2 epidemic with incomplete data

Designing public health responses to outbreaks requires close monitoring of population-level health indicators in real-time. Thus, an accurate estimation of the epidemic curve is critical. We propose an approach to reconstruct epidemic curves in near real time. We apply this approach to characterize the early SARS-CoV-2 outbreak in two Spanish regions between March and April 2020. We address two data collection problems that affected the reliability of the available real-time epidemiological data, namely, the frequent missing information documenting when a patient first experienced symptoms, and the frequent retrospective revision of historical information (including right censoring). This is done by using a novel back-calculating procedure based on imputing patients' dates of symptom onset from reported cases, according to a dynamically-estimated "backward" reporting delay conditional distribution, and adjusting for right censoring using an existing package, NobBS , to estimate in real time (nowcast) cases by date of symptom onset. This process allows us to obtain an approximation of the time-varying reproduction number ( R t ) in real-time. At each step, we evaluate how different assumptions affect the recovered epidemiological events and compare the proposed approach to the alternative procedure of merely using curves of case counts, by report day, to characterize the time-evolution of the outbreak. Finally, we assess how these real-time estimates compare with subsequently documented epidemiological information that is considered more reliable and complete that became available later in time. Our approach may help improve accuracy, quantify uncertainty, and evaluate frequently unstated assumptions when recovering the epidemic curves from limited data obtained from public health surveillance systems in other locations.

[Association of blood lead level with cognition impairment among elderly aged 65 years and older in 9 longevity areas of China]

Objective: To investigate the association between blood lead concentrations and cognition impairment among Chinese older adults aged 65 or over. Method: Data was collected in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study between 2017 and 2018. This study included 1 684 elderly aged 65 years and older. Information about demographic characteristics, socioeconomic factors, health status and cognitive function score of respondents were collected by questionnaire survey and physical examination. Venous blood of the subjects was collected to detect the blood lead concentration. Subjects were stratified into four groups (Q₁-Q₄) by quartile of blood lead concentration. Multivariate logistic regression model was used to analyze the association between blood lead concentration and cognitive impairment. The linear or non-linear association between blood lead concentration and cognitive impairment were described by restrictive cubic splines (RCS). Results: Among the 1 684 respondents, 843 (50.1%) were female and 191 (11.3%) suffered from cognition impairment. After adjusting for confounding factors, the OR value and 95%CI of cognition impairment was 1.05 (1.01-1.10) for every 10 μg/L increase in blood lead concentration in elderly; Compared with the elderly in Q₁, the elderly with higher blood lead concentration had an increased risk of cognitive impairment. The OR value and 95%CI of Q₂, Q₃ and Q₄ groups were 1.19 (0.69-2.05), 1.45 (0.84-2.51) and 1.92 (1.13-3.27), respectively. Conclusion: Higher blood lead concentration is associated with cognitive impairment among the elderly aged 65 years and older in 9 longevity areas in China.

[Association of blood oxidative stress level with hypertriglyceridemia in the elderly aged 65 years and older in 9 longevity areas of China]

Objective: To investigate the association of blood oxidative stress level with hypertriglyceridemia in the elderly aged 65 years and older in China. Methods: A total of 2 393 participants aged 65 years and older were recruited in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study, during 2017 to 2018. Information on demographics characteristic, life style and health status were collected by questionnaire and physical examination, and venous blood was collected to detect the levels of blood oxidative stress and hypertriglyceridemia. The linear or non-linear association between oxidative stress and hypertriglyceridemia was described by restrictive cubic splines (RCS) fitting multiple linear regression model. The generalized linear mixed effect model was conducted to assess the association between oxidative stress and hypertriglyceridemia. Results: A total of 2 393 participants, mean age was 84.6 years, the youngest was 65 and the oldest was 112, the male was 47.9%(1 145/2 393), the triglyceride level was (1.4±0.8) mmol/L. The hypertriglyceridemia detection rate was 9.99%(239/2 393). The results of multiple linear regression model with restrictive cubic spline fitting showed that MDA level was linear association with triglyceride level; SOD level was nonlinear association with triglyceride level. MDA level had significantly association with hypertriglyceridemia, and the corresponding OR value was 1.063 (95%CI: 1.046,1.081) with 1 nmol/ml increment of blood MDA; SOD level had significantly association with hypertriglyceridemia, and the corresponding OR value was 0.986(95%CI: 0.983,0.989) with 1 U/ml increment of blood SOD. Conclusion: Among the elderly aged 65 and older in 9 longevity areas in China, MDA and SOD levels were associated with the risk of hypertriglyceridemia.

Naphthalene Structures Derived from Lignins During Phenolation

Phenolation is a commonly used method to improve the reactivity of lignin for various applications. In this study, resinol lignin models (syringaresinol and pinoresinol) and eucalyptus alkali lignin were treated under acid-catalyzed phenolation conditions to investigate the products derived from resinol (β-β) structures of lignins. The phenolation products were characterized by means of GC-MS and NMR spectroscopy following separation using flash chromatography and thin-layer chromatography. A series of new naphthalene products were identified from phenolation of syringaresinol, and the corresponding guaiacyl analogs were also identified by GC-MS. The C1-Cα bond of these resinol compounds was cleaved to release syringol or guaiacol during phenolation. In addition, diphenylmethane products formed from phenol or phenol and syringol/guaiacol were found in the phenolation products. Comparatively, more naphthalene products were obtained by phenolation from syringaresinol than those obtained from pinoresinol. HSQC NMR characterization of the phenolated alkali lignin revealed that naphthalene structures formed in the phenolated lignin.

Denitrosylation of nNOS induced by cerebral ischemia-reperfusion contributes to nitrosylation of CaMKII and its inhibition of autophosphorylation in hippocampal CA1

OBJECTIVE

The aim of this study is to investigate the relation between CaMKII S-nitrosylation and its activation, as well as the underlying mechanism, after global cerebral ischemia-reperfusion.

MATERIALS AND METHODS

The rat model of cerebral ischemia-reperfusion was established by four-vessel occlusion of 15 min and reperfusion of different times. nNOS inhibitor 7-nitroindazole (7-NI), exogenous nitric oxide donor GSNO (nitrosoglutathione), or N-methyl-D-aspartate receptor (NMDAR) antagonist MK-801 were administered before ischemia. The expressions of S-nitrosylation and phosphorylation of CaMKII and nNOS were detected by biotin switch assay, immunoblotting, and immunohistochemical staining after cerebral ischemia-reperfusion. The survival of hippocampal CA1 pyramidal cells after administration of the three drugs was examined by cresyl violet staining.

RESULTS

Following cerebral ischemia-reperfusion, the S-nitrosylation of CaMKII was increased, accompanied by a decrease of phosphorylation, suggesting a decrease of activity (p<0.05). Meanwhile, the phosphorylation and S-nitrosylation of nNOS were notably decreased at the same time point (p<0.05). The administration of 7-NI, GSNO, and MK-801 increased the S-nitrosylation and phosphorylation of nNOS, leading to the attenuation of increased S-nitrosylation and decreased autophosphorylation of CaMKII after cerebral ischemia-reperfusion (p<0.05). Administration of MK-801, GSNO, and 7-NI significantly decreased the neuronal damage in rat hippocampal CA1 caused by cerebral ischemia-reperfusion (p<0.05).

CONCLUSIONS

After cerebral ischemia-reperfusion, the decrease of autophosphorylation of CaMKII regulated by its S-nitrosylation may be due to the denitrosylation of nNOS and subsequent NO production. Increasing the phosphorylation of CaMKII by nNOS inhibitor, exogenous NO donor or NMDA receptor antagonist exerted neuroprotective effects against cerebral ischemia-reperfusion injury.

The class II KNOX transcription factors KNAT3 and KNAT7 synergistically regulate monolignol biosynthesis in Arabidopsis

The function of the transcription factor KNOTTED ARABIDOPSIS THALIANA7 (KNAT7) is still unclear since it appears to be either a negative or a positive regulator for secondary cell wall deposition with its loss-of-function mutant displaying thicker interfascicular and xylary fiber cell walls but thinner vessel cell walls in inflorescence stems. To explore the exact function of KNAT7, class II KNOTTED1-LIKE HOMEOBOX (KNOX II) genes in Arabidopsis including KNAT3, KNAT4, and KNAT5 were studied together. By chimeric repressor technology, we found that both KNAT3 and KNAT7 repressors exhibited a similar dwarf phenotype. Both KNAT3 and KNAT7 genes were expressed in the inflorescence stems and the knat3 knat7 double mutant exhibited a dwarf phenotype similar to the repressor lines. A stem cross-section of knat3 knat7 displayed an enhanced irregular xylem phenotype as compared with the single mutants, and its cell wall thickness in xylem vessels and interfascicular fibers was significantly reduced. Analysis of cell wall chemical composition revealed that syringyl lignin was significantly decreased while guaiacyl lignin was increased in the knat3 knat7 double mutant. Coincidently, the knat3 knat7 transcriptome showed that most lignin pathway genes were activated, whereas the syringyl lignin-related gene Ferulate 5-Hydroxylase (F5H) was down-regulated. Protein interaction analysis revealed that KNAT3 and KNAT7 can form a heterodimer, and KNAT3, but not KNAT7, can interact with the key secondary cell wall formation transcription factors NST1/2, which suggests that the KNAT3-NST1/2 heterodimer complex regulates F5H to promote syringyl lignin synthesis. These results indicate that KNAT3 and KNAT7 synergistically work together to promote secondary cell wall biosynthesis.

Mild Acetylation and Solubilization of Ground Whole Plant Cell Walls in EmimAc: A Method for Solution-State NMR in DMSO-d6

Lignocellulosic biomass is mainly composed of polysaccharides and lignin. The complexity and diversity of the plant cell wall polymers makes it difficult to isolate the components in pure form for characterization. Many current approaches to analyzing the structure of lignocellulose, which involve sequential extraction and characterization of the resulting fractions, are time-consuming and labor-intensive. The present study describes a new and facile system for rationally derivatizing and dissolving coarsely ground plant cell wall materials. Using ionic liquids (EmimAc) and dichloroacetyl chloride as a solvent/reagent produced mildly acetylated whole cell walls without significant degradation. The acetylated products were soluble in DMSO-d₆ from which they can be characterized by solution-state two-dimensional nuclear magnetic resonance (2D NMR) spectrometry. A distinct advantage of the procedure is that it realizes the dissolution of whole lignocellulosic materials without requiring harsh ball milling, thereby allowing the acquisition of high-resolution 2D NMR spectra to revealing structural details of the main components (lignin and polysaccharides). The method is therefore beneficial to understanding the composition and structure of biomass aimed at its improved utilization.

FRI0259 THE CLINICAL VALUE OF GDF-15 IN ASSESSING MYOCARDIAL INVOLVEMENT OF IDIOPATHIC INFLAMMATORY MYOPATHY

Background:

Cardiac involvement is a serious complication of idiopathic inflammatory myopathy (IIM). Early diagnosis and intervention can improve prognosis. At present, myocardial biopsy is the gold standard for its diagnosis, but it is not commonly used because of its invasiveness. Biomarkers can be invoked as a non-invasive and convenient choice. The traditional markers of myocardial injury, as troponin and creatine kinase are lack specificity in inflammatory myopathy, so the novel biomarkers are getting attention.GDF-15 can predict the risk of cardiovascular disease and the prognosis of coronary atherosclerosis, heart failure and other diseases.

Objectives:

This article was intended to investigate the diagnostic value of GDF-15 for myocardial involvement in inflammatory myopathy.

Methods:

This retrospective study included 54 patients with inflammatory myopathy from May 2018 to October 2019.Of these,30 patients underwent cardiac magnetic resonance examination due to increased myocardial markers, excluding 1 case of severe lung infection. 33 patients with systemic lupus erythematosus (SLE),16 normal patients were used as the control group.The concentration of GDF-15 in the serum of all groups of patients was measured by ELISA.

Results:

1. There were significantly differences in GDF-15 levels in patients with inflammatory myopathy, systemic lupus erythematosus and normal subjects (H =39.870, P <0.001).2. 29 patients with cardiac magnetic resonance on the basis of the delayed enhancement (LGE) and ECV results were divided into two groups in which 19 patients with myocardial injury group and 10 patients without myocardial injury. The best cut-off value was calculated by ROC curve,and comparing GDF-15 and CKMB with the optimum cut-off values in predicting cardiac involvement in IIM.GDF-15 levels were statistically significant between the myocardial injury group (1765.868±1068.549 pg/ml) and the group without myocardial injury(689.967±458.12 pg/ml)(p =0.0011).At the same time, the creatine kinase isoenzyme (CKMB)(158.583±119.389 U/L vs 57.96±52.673 U/L, p =0.005) was statistically different between the two groups.3.GDF-15≥1005.3650pg/ml (AUC =0.853,95% CI 0.694-1.000) predicted myocardial involvement in inflammatory diseases with a sensitivity of 0.765 and specificity of 0.900.The AUC of the ROC curve for the joint detection of GDF-15 and CKMB was 0.888,95% CI0.757-1.000,with the predicted probability cut-off value in 0.3895, the sensitivity 0.941 and the specificity 0.800.The combined detection of the two increased the sensitivity of myocardial damage detection in IIM patients. 5. After adjusted for age, renal function, the risk of myocardial injury in IIM patients increased by an average of 0.3% per unit of GDF-15(OR =1.003,95% CI 1.000–1.005).

Conclusion:

GDF-15 can predict myocardial injury in patients with inflammatory myopathy which have high specificity.The prediction sensitivity can be improved by combining with the traditional myocardial enzyme CKMB.More further studies are needed to confirm the specific mechanism of GDF-15 for myocardial involvement to assess the prognosis of such patients and guide further treatment.

References:

[1]Sultan SM, Ioannou Y, Moss K, Isenberg DA. Outcome in patients with idiopathic inflflammatory myositis: morbidity and mortality. Rheumatology (Oxford) 2002;41:22–6.

[2]Lundberg IE, de Visser M, Werth VP. Classification of myositis. Nat Rev Rheumatol. 2018 May;14(5):269-278.

[3]Zhang L, Wang GC, Ma L, Zu N (2012) Cardiac involvement in adult polymyositis or dermatomyositis: a systematic review. Clin Cardiol 35(11):686–691.

[4]Chen F,Peng Y,Chen M. Diagnostic approach to cardiac involvement in idiopathic inflammatory myopathies.A strategy combining cardiac troponin I but not T assay with other methods[J].Int Heart J,2018;59:256-262

Disclosure of Interests:

None declared

Transinguinal preperitoneal repair of giant inguinoscrotal hernias using Kugel mesh

INTRODUCTION

Giant inguinoscrotal hernias are rarely encountered in clinical settings, and their repair is technically challenging. The aim of this study is to evaluate the efficacy of transinguinal preperitoneal repair (TIPP) of giant inguinoscrotal hernias using Kugel mesh.

METHODS

A retrospective analysis was conducted on 9 patients with 11 giant inguinoscrotal hernias who underwent TIPP repair using Kugel mesh between December 2008 and January 2019. Demographics and perioperative and postoperative data were collected, and the operative experience was summarized.

RESULTS

The patients underwent a successful repair procedure with simultaneous omentectomy but without resection of the other abdominal organs. The median operation time was 120min, the median intraoperative blood loss was 75mL and the median defect area was 72 cm². The median duration for diet restoration was 4 days, and the median postoperative hospital stay was 6 days. The drainage tube placed in the preperitoneal space was removed after a median duration of 5 days, and the drainage tube placed in the distal hernia sac was removed after a median duration of 6 days. Three patients suffered from a postoperative increase in intra-abdominal pressure, while one patient deteriorated into abdominal compartment syndrome accompanied by respiratory dysfunction. No haematomas, seromas, incisional or mesh infections, recurrence or chronic pain occurred during the follow-up period.

CONCLUSIONS

TIPP repair using Kugel mesh is a feasible and effective method for giant inguinoscrotal hernias.

New Products Generated from the Transformations of Ferulic Acid Dilactone

Various ferulic acid (FA) dimers occurring in plant cell walls, such as 8-5-, 8-O-4-, 5-5-, and 8-8- coupled dimers, are effective antioxidants and potential antimicrobials. It is necessary to access these diferulates as reference compounds to validate those isolated from plants. 3,6-bis(4-hydroxy-3-methoxyphenyl)-tetrahydrofuro-[3,4-c]furan-1,4-dione, a 8-8-coupled FA dilactone generated from ferulic acid via radical coupling, has been used to synthesize 8-8-coupled FA dimers although few reports investigated the distribution of products and mechanisms involved in the transformation of FA dilactone. In this work, the FA dilactone, obtained from FA by a peroxidase-catalyzed radical coupling, was reacted under various base/acid conditions. Effects of reaction conditions and workup procedures on the distribution of products were investigated by GC-MS. The isolated products from such treatments of FA dilactone were characterized by NMR. New derivatives of FA dimer including 2-(4-hydroxy-3-methoxybenzylidene)-3-(hydroxyl-(4-hydroxy-3-methoxyphenyl)methyl)succinic acid and 2-(bis(4-hydroxy-3-methoxyphenyl)-methyl)-succinic acid were produced from NaOH treatment. Another novel 8-8-coupled cyclic FA dimer, diethyl 6-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-methoxy-1,2-dihydronaphthalene-2,3-dicarboxylate was identified in products from FA dilactone treated by dry HCl in absolute ethanol. Mechanisms involved in such transformations were proposed.

Revealing Structural Modifications of Lignin in Acidic γ-Valerolactone-H2O Pretreatment

γ-valerolactone (GVL)/H₂O/acid solvent mixtures has been used in chemical pretreatment of lignocellulosic biomass, it was claimed that GVL lignins were structurally close to proto (native) lignins, or having low molecular weight with narrow polydispersity, however, the structural changes of GVL lignins have not been investigated. In this study, β-O-4 (β-aryl ether, GG), β-5 (phenylcoumaran), and β-β (resinol) lignin model compounds were treated by an acidic GVL-H₂O solvent system, a promising pretreatment of lignocellulose for biomass utilization, to investigate the structural changes possibly related to the lignin involved. NMR characterization of the products isolated from the treated GG indicated that a phenyl dihydrobenzofuran, having typical C-H correlations at δ_C/δ_H 50.74/4.50 and 93.49/4.60 ppm in its HSQC spectrum, was produced from GG. In the pretreatment, the released formaldehyde from GG reacted fast with GG to form a novel 1,3-dioxane intermediate whose characteristic HSQC signals were: δ_C/δ_H 94.15–94.48/4.81–5.18 ppm and 80.82–83.34/4.50–4.94 ppm. The β-5 model, dihydrodehydrodiconiferyl alcohol, was converted into phenylcoumarone and stilbene having benzaldehyde that resulted from the allyl alcohol side chain. The β-β model, syringaresinol, was isomerized to form a mixture of syringaresinol, epi-, and dia-syringaresinol although being degraded slightly.