The substrate specificity in the O-demethylation of 4-alkylguaiacols by Cytochrome P450 AgcAP450

Alkylguaiacols are lignin-derived products obtained by reductive catalytic fractionation (RCF) of lignocellulosic biomass. Recently discovered AgcAP450 enzyme from CYP255A1 family oxidizes a range of 4-alkylguaiacols, having a preference for bulkier...

[Development of a risk assessment scale and test of its validity and reliability for venous thromboembolism in adult burn patients]

Objective: To develop a venous thromboembolism (VTE) risk assessment scale for adult burn patients and to test its reliability and validity. Methods: The scale research method and multi-center cross-sectional survey method were used. Based on the results of literature analysis method and brain-storming method, the letter questionnaire for experts was formulated. Then 27 experts (9 doctors of burn department, 9 vascular surgeons, and 9 nurses) were performed with two rounds of correspondences by Delphi method, and the reliability of the experts was analyzed. The weight of each item was determined by optimal sequence diagram method and expert importance evaluation to form the VTE Risk Assessment Scale for Adult Burn Patients. A total of 223 adult burn inpatients, who were admitted to 5 tier Ⅲ grade A general hospitals including the Affiliated Hospital of Southwest Medical University, West China Hospital of Sichuan University, the Affiliated Hospital of North Sichuan Medical College, Nanchong Central Hospital, and the Second People's Hospital of Yibin City from October 1st 2019 to January 1st 2020, were selected as respondents by convenience sampling method. The first assessment was performed with the VTE Risk Assessment Scale for Adult Burn Patients within 24 hours of admission of patients, and real-time assessment was performed as the patients' condition and treatment changed. The highest value was taken as the result. Correlation coefficient method and critical ratio method were used for item analysis; Cronbach's α coefficient was used to test the internal consistency of scale; content validity index was used to analyze the content validity of the scale, and receiver's operating characteristic (ROC) curve was drawn to test the predictive validity of the scale. Data were statistically analyzed with chi-square test, Pearson correlation analysis, independent sample t test, and Z test. Results: As four questionnaires in the first round of correspondence were rejected as unqualified, and another 4 experts were selected for the 2 rounds of correspondence. Most of them were aged 41 to 50 years with postgraduate degrees, engaging in the current profession for 11 to 30 years, and all of them had professional titles of associate senior or above. The scale, constructed through literature analysis, group brainstorming, and two rounds of correspondence, includes 3 primary items and 50 secondary items. In the first round of correspondence, the recovery rate of valid questionnaires and the ratio with expert opinions were 85.2% (23/27) and 47.8% (11/23), respectively. In the second round of correspondence, the recovery rate of valid questionnaires and the ratio with expert opinions were 100% (27/27) and 11.1% (3/27), respectively. The average collective authority coefficients of experts were both 0.90 in the 2 rounds of correspondence. The mean values of importance assignment, full score rate, and selection rate above 4 were 4.21, 52.5%, and 77.2%, respectively, in the first round of correspondence, and 4.28, 45.2%, and 85.8%, respectively, in the second round of correspondence. The mean coefficients of variation and the mean value of Kendall's coefficient of harmony for each item were 0.21 and 0.30 in the first round of correspondence, respectively, and 0.16 and 0.36 in the second round of correspondence, respectively. In the first and second rounds of correspondence, the Kendall's coefficients of harmony of 3 primary items (age and underlying diseases, burn injury factors, and burn treatment factors) and total secondary items were statistically significant (with χ2 values of 121.46, 107.09, 116.00, 331.97, 169.97, 152.12, 141.54, and 471.70, P<0.01). The weights of primary items for age and underlying diseases, burn injury factors, and burn treatment factors were 0.04, 0.05, and 0.07, respectively. The weights of secondary items ranged from 0.71 to 0.99, with assigned values of 3 to 6. The total burn area of 223 patients ranged from 1% to 89% total body surface area, and the patients were aged from 19 to 96 years, with the risk assessment score from 0 to 98. Nine patients developed VTE, with a risk assessment score of 41 to 90. The scores of 37 items were significantly positively correlated with the total score of scale (with r values of 0.14 to 0.61, P<0.05 or P<0.01), and the items were retained. There were 36 secondary items with statistically significant differences between the patients in high-score group and low-score group (with Z values of -4.88 to -2.09, t values of -11.63 to -2.09, P<0.05 or P<0.01), and the items were retained. The total Cronbach's α coefficient of scale was 0.88. The total content validity index of scale was 0.95. The optimal threshold of the scale for the diagnosis of VTE was 40, at which the sensitivity was 88.9%, the specificity was 87.4%, the Youden index was 0.87, and the area under the ROC curve was 0.96 (with 95% confidence interval of 0.93 to 0.99, P<0.01). Conclusions: The age and underlying diseases, burn injury factors, and burn treatment factors are the risk factors for VTE in adult burn patients. The VTE risk assessment scale for adult burn patients developed based on these factors has good reliability and validity, and provide good reference value for clinical VTE risk assessment.

[Efficacy and safety of omalizumab in patients with refractory allergic asthma: a meta-analysis]

Objective: To evaluate the efficacy and safety of omalizumab in patients with refractory allergic asthma using meta-analysis. Methods: We searched databases including PubMed, Web of Science, Embase and the website of ClinicalTrials. gov registry for randomized controlled trials (RCTs), using the search terms: ("anti-IgE" OR "anti-immunoglobulin E" OR "anti-IgE antibody" OR "omalizumab" OR "rhuMAb-E25" OR "Xolair") AND ("allergic asthma"). The time was up to September 19th 2020. Review Manager 5.4 software and Stata16 software were used to calculate pooled RR or WMD, perform heterogeneity test, and assess publication bias. Results: Fifteen RCTs with 6 316 patients in total (omalizumab, n=3 469; placebo, n=2 847) met our selection criteria. Comparing with placebo, omalizumab reduced the risk of asthma exacerbations during both stable-inhaled corticosteroid (ICS) phase (RR=0.69, 95%CI: 0.63-0.75, P<0.001; I²=39.0%, P=0.090) and ICS-reduction phase (RR=0.55, 95%CI: 0.46-0.66, P<0.001; I²=41.0%, P=0.180), reduced emergency visits (RR=0.53, 95%CI: 0.38-0.73, P<0.001; I²=0, P=0.420), made a significant reduction in dosage of ICS (RR=1.35, 95%CI: 1.25-1.45, P<0.001; I²=22.0%, P=0.280) and even withdrew from ICS completely (RR=1.80, 95%CI: 1.41-2.31, P<0.001; I²=57.0%, P=0.070). Omalizumab significantly improved asthma-related quality of life (RR=1.81, 95%CI: 1.51-2.17). The use of rescue bronchodilators was significantly reduced in the omalizumab group (RR=0.78, 95%CI: 0.67-0.92) but there was no significant difference in the dosage of rescue bronchodilators (puff per day) (WMD=-0.32, 95%CI: -0.77-0.13). Patients taking omalizumab did not increase the frequency of any adverse events (RR=1.01, 95%CI: 0.98-1.03) and serious adverse events (RR=0.89, 95%CI: 0.74-1.06). Conclusions: Omalizumab is an ideal adjunctive treatment for refractory allergic asthma with good efficacy and safety. Further randomized controlled trials are needed to determine the appropriate duration of treatment.

[Application of anti-programmed cell death protein 1 antibody in children with refractory or relapsed Hodgkin lymphoma]

Objective: To explore the efficacy of anti-programmed cell death protein 1 (PD-1) antibody for children with refractory or relapsed Hodgkin lymphoma. Methods: Clinical data including short-term efficacy, long-term efficacy and adverse reaction of Hodgkin lymphoma children treated with anti-PD-1 antibody in Beijing Children's Hospital, Capital Medical University from December 2017 to June 2021 were analyzed retrospectively. Efficacy was evaluated as complete remission (CR), partial remission (PR), stable disease (SD), progressed disease (PD) and no response. Results: A total of 6 cases were included, including 5 males and 1 female. The age at the start of anti-PD-1 antibody treatment was 11.6 (10.2, 13.3) years, including 3 cases of mixed cellularity type, 2 cases of nodular sclerosis type, and 1 case of nodular lymphocyte-predominant type. There were 4 cases of stage Ⅳ and 2 cases of stage Ⅲ. All cases were assigned to the high-risk group, and 5 cases had B symptoms, all cases were refractory or relapsed Hodgkin lymphoma before the start of anti-PD-1 antibody treatment. Early evaluation showed that within 12 weeks of the treatment, 3 cases achieved PR and 3 cases achieved SD, while late evaluation showed that after 16 weeks of the treatment, 5 cases achieved CR and 1 case achieved PR. None of the children progressed during treatment. The follow-up time was 27 (21,41) months. Among all cases, 5 cases had event-free survival and sustained remission, 1 case had fever about 4 weeks after the drug withdrawal, finally he was confirmed to be transformed to B cell lymphoma between diffuse B cells and classic Hodgkin lymphoma. All the patients were well tolerated with anti-PD-1 antibody therapy. No adverse reactions such as high fever, chills, rash, etc. were observed during infusion. None of the patients were delayed, dose reduction or withdrawal due to adverse reactions. Two cases had reactive skin vascular hyperplasia during the treatment, without pain or itching, and they recovered on their own after stopping anti-PD-1 antibody therapy without other special treatment. Conclusion: Anti-PD-1 monoclonal antibody for children with refractory or relapsed Hodgkin lymphoma have good efficacy and tolerable side effects.

POS0482 LONG NON-CODING RNA H19X IS A MEDIATOR OF ENDOTHELIAL CELL ACTIVATION IN SYSTEMIC SCLEROSIS

Background

In one of our previous studies, we demonstrated that long non-coding RNA (lncRNA) H19X plays a crucial role in the development of TGFβ driven fibrosis in systemic sclerosis (SSc) and other fibrotic diseases1.

Objectives

To define the functional relevance of H19X in endothelial cell (EC) activation as a decisive process in SSc vasculopathy.

Methods

Correlation of H19X expression and microvascular gene signature was computed on bulk RNA-Seq data derived from SSc skin biopsies of patients enrolled in the multicentre Prospective Registry of Early Systemic Sclerosis cohort (PRESS, n=48 SSc vs. n=33 healthy controls, HCs). Single cell RNA sequencing (scRNA-seq) data were collected from 27 diffuse cutaneous SSc (dcSSc) and 10 HC skin biopsies. Single cells were barcoded and encapsulated in droplets using a 10X Genomics system. After cDNA synthesis, the libraries were prepared and sequenced using Illumina NovaSeq-500 platform. Seurat package in R (v.3.0) was used to perform data analysis. EC were identified by enrichment of EC markers CLDN5, VWF and PECAM1. One thousand five hundred eighty-three and 3398 EC were identified from HC and SSc patients, respectively. Cells were analysed for the expression of H19X and EC activation markers. Additionally, differential expression and pathway enrichment analysis between H19X expressing cells and H19X negative cells was carried out. The function of H19X was investigated in human dermal microvascular EC (HDMEC) by silencing, using locked nucleic acid antisense oligonucleotides (LNA GapmeRs). Gene expression was measured by qPCR. Protein levels of endothelial adhesion molecules were analysed by Western Blot. Endothelial adhesion was evaluated by co-culture of HDMEC and fluorescently labelled peripheral blood mononuclear cells (PBMCs).

Results

H19X expression was found significantly upregulated in SSc skin biopsies of the PRESS cohort (p<0.0001). The expression of H19X positively correlated with the microvascular endothelial cell gene signature in all subjects (SSc and HC, R=0.43, p<0.0001), confirming that H19X is expressed in this cell type. To determine if H19X might be an important factor in SSc EC dysfunction scRNAseq was performed. This analysis revealed a significant upregulation of H19X in SSc EC as compared to HC EC (p=0.0095). H19X was found to be upregulated in several EC subclusters including arterial (SEMA3G, HEY1), capillary (CA4, RGCC), venous (ACKR1, VCAM1) and lymphatic (PROX1, LYVE1). H19X displayed highest expression in injured SSc EC and capillary SSc EC. Co-expression analysis of the scRNA-seq data revealed higher expression of several adhesion molecules in EC expressing H19X, including VCAM1, ICAM and JAM3. KEGG pathway analysis revealed that differentially expressed genes in H19X expressing cells were highly associated with the ‘Cell adhesion molecule’ pathway (p=2.209e-7). H19X silencing lead to a significant downregulation of mRNA levels of genes encoding adhesion molecules VCAM1 (n=7, p<0.05) and E-selectin (n=7, p<0.01) at 48h after transfection. VCAM1, but not E-Selectin, was also reduced at protein level as revealed by Western Blot (n=3). The functional relevance of H19X on endothelial adhesion was confirmed by PBMCs with H19X silenced HDMEC where we were able to demonstrate a significant decrease in leucocyte-to-endothelial cell adhesion (n=5, p<0.05).

Conclusion

Our results show that lncRNA H19X could contribute to EC activation in SSc vasculopathy, acting as a regulator of expression of adhesion molecules in EC.

References

[1]Pachera E, et al. Long noncoding RNA H19X is a key mediator of TGF-β-driven fibrosis. J Clin Invest. 2020 Sep 1;130(9):4888-4905.

Disclosure of Interests

Francesca Tirelli: None declared, Elena Pachera: None declared, Robert Lafyatis Consultant of: Pfizer, Bristol Myers Squibb, Boehringer-Ingleheim, Formation, Sanofi, Boehringer-Mannheim, Merck and Genentech/Roche, Grant/research support from: Corbus, Formation, Moderna, Regeneron, Pfizer and Kiniksa, Menqi Huang: None declared, Shervin Assassi: None declared, Eva Camarillo: None declared, Francesco Zulian: None declared, Gabriela Kania: None declared, Oliver Distler Speakers bureau: Bayer, Boehringer Ingelheim, Janssen, Medscape, Consultant of: Abbvie, Acceleron, Alcimed, Amgen, AnaMar, Arxx, AstraZeneca, Baecon, Blade, Bayer, Boehringer Ingelheim, Corbus, CSL Behring, 4P Science, Galapagos, Glenmark, Horizon, Inventiva, Kymera, Lupin, Miltenyi Biotec, Mitsubishi Tanabe, MSD, Novartis, Prometheus, Roivant, Sanofi and Topadur, Grant/research support from: Kymera, Mitsubishi Tanabe, Boehringer Ingelheim.

[Dynamic changes of locus coeruleus damage in Parkinson's disease-like mice induced by paraquat]

Objective: To observe the dynamic changes of brainstem locus coeruleus (LC) damage in Parkinson' s disease (PD) -like mice by paraquat (PQ) . Methods: In October 2019, 36 male C57BL/6 mice were randomly divided into the exposure group and the control group, with 18 mice in each group. The mice in the exposure group were given intraperitoneal injection of 15 mg/kg PQ, and the mice in the control group were given intraperitoneal injection of 0.9% saline, twice a week for 8 weeks. Neurobehavioral changes (pole climbing test, swimming test, open field test, tail hanging test, high plus maze test and water maze test) were observed at 4 weeks, 6 weeks and 8 weeks, respectively, and the changes of motor ability, emotion and cognitive function were evaluated. The brain tissue of mice were taken and stained with Hematoxylin-Eosin (HE) to observe the pathological changes of LC. Nissl staining was used to detect the changes of neuronal Nissl bodies in LC. Immunohistochemistry (IHC) staining was used to detect the expression of neuron nuclear antigen (NeuN) , dopamine (DA) neurons and norepinephrine (NE) neuron markers tyrosine hydroxylase (TH) , α-synuclein (α-syn) in substantia nigra (SN) and LC. The expression levels of NeuN, TH and α-syn in the midbrain and brainstem were detected by Western blotting. TUNEL staining was used to detect neuronal apoptosis in LC. Results: Compared with the 4th week of PQ exposure group, the time of pole climbing and swimming immobility were gradually increased, the ratio of open arm residence time of high plus maze test and the number of times of the platform and the residence time of platform quadrant in water maze test were gradually decreased (P<0.05) in the exposure group with the progress of exposure time. The results of HE and Nissl staining showed that the neurons in LC gradually arranged loosely, the nucleus were deeply stained, the cytoplasm was pyknosis, and the number of Nissl bodies gradually decreased (P<0.05) in the exposure group with the progress of exposure time. IHC results showed that the number of NeuN and TH positive cells in SN and LC of mice were gradually decreased, and the positive expression of α-syn was gradually increased (P<0.05) in the exposure group with the progress of exposure time. Western blotting results showed that the expression levels of NeuN and TH in the midbrain and brainstem were gradually decreased, and the expression level of α-syn was gradually increased (P<0.05) in the exposure group with the progress of exposure time. TUNEL staining showed that the apoptosis rates of neurons in LC were gradually increased (P<0.05) in the exposure group with the progress of exposure time. Conclusion: PQ induces progressive damage in the LC area of PD-like mice, which may be caused by the abnormal accumulation of pathological α-syn in the LC area.

Polydatin Improves Sepsis-Associated Encephalopathy by Activating Sirt1 and Reducing p38 Phosphorylation

INTRODUCTION

Our previous study confirmed that polydatin (PD) can alleviate sepsis-induced multiorgan dysfunction (in the vascular endothelium, kidney, and small intestine) by activating Sirt1 and that PD protects against traumatic brain injury in rats via increased Sirt1 and inhibition of the p38-mediated mitogen-activated protein kinase (MAPK) pathway. We aim to investigate whether PD may also attenuate sepsis-associated encephalopathy (SAE).

METHODS

In this study, we constructed an SAE mouse model by cecal ligation and puncture (CLP) and measured Sirt1 protein activity, p38 phosphorylation, brain tissue pathological damage, pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), mitochondrial function (mitochondrial membrane potential, ATP content, and reactive oxygen species), neurological function, and animal survival time. Sirt1 selective inhibitor Ex527 and p38 inhibitor SB203580 were used to explore the possible mechanism of PD in SAE.

RESULTS

We confirmed that PD inhibits neuroinflammation evidenced by reduced proinflammatory cytokines. In addition, PD protects mitochondria as demonstrated by restored mitochondrial membrane potential and adenosine triphosphate (ATP) content, and decreased reactive oxygen species (ROS) level. As we expected, p38 inhibition reduces neuroinflammation and mitochondrial damage. In contrast, Sirt1 inhibition aggravates cerebral cortex mitochondrial damage and neuroinflammation and promotes phosphorylation of p38. Mechanistically, PD treatment suppressed p38 phosphorylation and consequently reduced the neuroinflammatory response, and these effects were blocked by the Sirt selective inhibitor Ex527.

CONCLUSIONS

This study, to the best of our knowledge, is the first to demonstrate that PD alleviates SAE, at least partially, by upregulating Sir1-mediated neuroinflammation inhibition and mitochondrial function protection.

[Preliminary study on time-dependent changes of intestinal tract and brain-gut axis in mice model of Parkinson's disease induced by paraquat]

Objective: To observe the intestinal time-dependent changes in Parkinson's disease (PD) mouse model constructed by intraperitoneal injection of paraquat (PQ) and to establish the brain-gut axis connection initially. Methods: In October 2019, 48 mice were randomly divided into treated group and control groups: treated 4-week (P-4) group, treated 6-week (P-6) group, treated 8-week (P-8) group, control 4-week (C-4) group, control 6-week (C-6) group, and control 8-week (C-8) group. The treated group was injected with 15 mg/kg PQ solution and the control group was injected with 0.9% saline (0.2 ml/20 g) by intraperitoneal injection twice a week. After the initial state (0 weeks) and the treatment at the end of 4, 6 and 8 weeks, the mood changes and motor functions of mice were assessed by neurobehavioral tests (open field test, pole climbing test, tail suspension test and elevated plus maze test) . And the number of fecal pellets for 1 h and water content were calculated to assess the functional status of the gastrointestinal tract. Western blotting experiments were performed to detect the expression levels of α-synuclein (α-syn) and tyrosine hydroxylase (TH) in the nigrostriatal region of the mouse brain, the tight junction markers zonula occludens-1 (ZO-1) and Occludin, the inflammatory markers of integrin αM subunit (CD11b) , inducible nitric oxide synthase (iNOS) , high mobility group box 1 (HMGB1) , interleukin-1β (IL-1β) , and the neuronal markers βⅢ-tubulin and α-syn protein in the colon.Immunohistochemical staining was performed to detect the expression levels of colonic tight junction proteins ZO-1 and Occludin. Immunofluorescence staining was performed to detect the expression levels of TH in the substantia nigra region of the midbrain, and the co-localization of colonic intestine neuronal marker (βⅢ-tubulin) and Ser129 α-syn in the colonic. Results: Compared with the initial state (0 weeks) and C-8 group, mice in the P-8 group had significantly higher pole climbing test scores and resting time, and significantly lower total active distance, mean active speed, percentage of open arm entry and 1 h fecal instances (P<0.05) . After poisoning, the 1 h fecal water content of model mice first increased and then decreased, the P-4 and P-6 groups were significantly higher than the simultaneous point control group, and the P-8 groups were significantly lower than the initial state (P<0.05) . Compared with control, P-4 and P-6 groups, the expression levels of ZO-1 and Occludin in the P-8 group were significantly decreased (P<0.05) . Compared with control group, the expression levels of CD11b and IL-1β in the P-4 group were significantly increased (P<0.05) . Compared with control and P-4 group, the expression levels of CD11b, iNOS, HMGB1 and IL-1β in the P-6 and P-8 groups were significantly increased (P<0.05) . Compared with the control and P-4 groups, the expression levels of βⅢ-tubulin in the colon of mice in the P-8 group were significantly decreased, and the expression levels of α-syn and Ser129 α-syn were significantly increased (P<0.05) . The expression level of Ser129 α-syn in the colon of model mice was negatively correlated with the expression level of βⅢ-tubulin (r(s)=-0.9149, 95%CI: -0.9771--0.7085, P<0.001) . Ser129 α-syn and βⅢ-tubulin co-localization in the colonic intermuscular plexus region increased gradually with the time of exposure. Compared with the control, P-4 and P-6 groups, the expression level of TH in the nigrostriatal region of the brain was significantly decreased, and the expression levels of α-syn and Ser129 α-syn were significantly increased in the P-8 group (P<0.05) . Correlation analysis showed that the relative expression level of Ser129 α-syn in the nigrostriatal region of the brain was negatively correlated with the expression level of TH in the model mice (r(s)=-0.9716, 95% CI: -0.9925--0.8953, P<0.001) . Conclusion: The PD mouse model is successfully established by PQ, and the intestinal function of the model mice is reduced in a time-dependent manner. And on this basis, it is preliminary determined that the abnormal aggregation of α-syn may be an important substance connecting the brain-gut axis.

Explainable deep neural network for echocardiography view classification

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science and Technology, Taiwan

Background

Deep neural network may assist echocardiography interpretation in several tasks; however, the lack of expandability hindered its broader application since physicians couldn’t realize the rationale of interpretation clearly and comfortably.

Method

Retrospectively, we manually annotated 26,465 transthoracic echocardiography images into 29 classes for model development in 4:1 ratio as training and validation datasets. We added an autoencoder component into our model, adapted from capsule net, for view-classifying to deconvolute the feature maps of last layer as decoder for human interpretation. The performance of view classification was measured in accuracy and confusion matrix, and the interpretability of model were assessed by cardiologist.

Result

After appropriate model training, the accuracy of our model achieved averaged 98.2% for echocardiography view classification, ranged from lowest 80.0% in suprasternal view to 100% of several more common view in validation dataset. The successful deconvolution of feature map to reconstruct images showed essential independent components of echocardiography view and could be interpretated by cardiologist and clinical physicians.

Conclusion

With the use of autoencoder in model for echocardiography view classification showed maintainable good performance in accuracy and facilitated clinical interpretation to enhance its reliability. Abstract Figure. Model architecture and performance  Abstract Figure. Example of explaniable deconvolution