Adapting to stress: The effects of hibernation and hibernacula temperature on the hepatic transcriptome of Rhinolophus pusillus

Hibernation, a survival strategy in mammals for extreme climates, induces physiological phenomena such as ischemia-reperfusion and metabolic shifts that hold great potential for advancements in modern medicine. Despite this, the molecular mechanisms underpinning hibernation remain largely unclear. This study used RNA-seq and Iso-seq techniques to investigate the changes in liver transcriptome expression of Rhinolophus pusillus during hibernation and active periods, as well as under different microhabitat temperatures. We identified 11 457 differentially expressed genes during hibernation and active periods, of which 395 showed significant differential expression. Genes associated with fatty acid catabolism were significantly upregulated during hibernation, whereas genes related to carbohydrate metabolism and glycogen synthesis were downregulated. Conversely, immune-related genes displayed differential expression patterns: genes tied to innate immunity were significantly upregulated, while those linked to adaptive immunity and inflammatory response were downregulated. The analysis of transcriptomic data obtained from different microhabitat temperatures revealed that R. pusillus exhibited an upregulation of genes associated with lipid metabolism in lower microhabitat temperature. This upregulation facilitated an enhanced utilization rate of triglyceride, ultimately resulting in increased energy provision for the organism. Additionally, R. pusillus upregulated gluconeogenesis-related genes regardless of the microhabitat temperature, demonstrating the importance of maintaining blood glucose levels during hibernation. Our transcriptomic data reveal that these changes in liver gene expression optimize energy allocation during hibernation, suggesting that liver tissue adaptively responds to the inherent stress of its function during hibernation. This study sheds light on the role of differential gene expression in promoting more efficient energy allocation during hibernation. It contributes to our understanding of how liver tissue adapts to the stressors associated with this state.

Dose-related effects of early-life intake of sn-2 palmitate, a specific positionally distributed human milk fatty acid, on the composition and metabolism of the intestinal microbiota

sn2 Palmitate in human milk plays an important role in the physiological health of infants by reducing mineral loss, improving stool hardness, and relieving constipation. Also, sn-2 palmitate modulates intestinal microbiota. However, it remains unclear whether the effects of sn-2 palmitate on infant gut microbiota are dose-dependent. In this study, we investigated the effects of low, medium, and high doses (600, 1,800, and 5,400 mg/kg body weight, respectively) of sn-2 palmitate on the structure, composition, and metabolic function of intestinal microbes in mice. Our results showed that high doses of sn-2 palmitate significantly modulated α- and β-diversity of the intestinal microbiota. The relative abundance of Lachnospiraceae_NK4A136_group decreased with increasing doses of sn-2 palmitate. In contrast, the abundances of Bacteroidetes phylum, Bacteroides, uncultured_Lachnospiraceae, and uncultured_Muribaculaceae were positively correlated with sn-2 palmitate doses. The number of genes predicted encoding autophagy-yeast, phospholipase D signaling pathway, and pentose and glucuronate interconversion metabolic functions of intestinal microbiota increased with increasing doses of sn-2 palmitate. In addition, low and medium doses of sn-2 palmitate significantly upregulated the arginine and proline metabolic pathways, and high doses of sn-2 palmitate significantly increased purine metabolism. Our results revealed that the effects of sn-2 palmitate intake early in life on the composition and metabolism of the intestinal microbiota of mice showed dose-related differences. The study is expected to provide a scientific basis for the development of infant formulas.

Deep Learning-Based Multi-Modality Segmentation of Primary Gross Tumor Volume in CT and MRI for Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

The delineation of primary gross tumor volume (GTV) of nasopharyngeal carcinoma (NPC) is an essential step for radiotherapy planning. In clinical practice, radiation oncologists manually delineate the GTV in planning CT with the help of diagnostic MRI. This is because NPC tumors are closely adjacent to many important anatomic structures, and CT and MRI provide complementary strength to accurately determine the tumor extension boundary. Manual delineation is time-consuming with the potential registration errors between MRI and CT decreasing the delineation accuracy. In this study, we propose a fully automated GTV segmentation method based on CT and MRI by first aligning MRI to CT, and then, segmenting the GTV using a multi-modality deep learning model.

MATERIALS/METHODS

We collected 104 nasopharyngeal carcinoma patients with both planning CT and diagnostic MRI scans (T1 & T2 phases). An experienced radiation oncologists manually delineated the GTV, which was further examined by another senior radiation oncologist. Then, a coarse to fine cross-modality registration from MRI to CT was conducted as follows: (1) A rigid transformation was performed on MRI to roughly align MRI to CT with similar anatomic position. (2) Then, the region of interest (RoI) on both CT and rigid-transformed MRI were cropped. (3) A leading cross-modality deformable registration algorithm, named DEEDS, was applied on the cropped MRI and CT RoIs to find an accurate local alignment. Next, using CT and registered MRI as the combined input, a multi-modality deep segmentation network based on nnUNet was trained to generate the GTV prediction. 20% patients were randomly selected as the unseen testing set to quantitatively evaluate the performance.

RESULTS

The quantitative NPC GTV segmentation performance is summarized in Table 1. The deep segmentation model using CT alone achieved reasonable high performance with 76.6% Dice score and 1.34mm average surface distance (ASD). When both CT and registered MRI were used, the segmentation model further improved the performance by 0.9% Dice score increase and 11% relative ASD error reduction, demonstrating the complementary strength of CT and MRI in determining NPC GTV. Notably, the achieved 77.5% Dice score and 1.19mm ASD by the multimodality model is among the top performing results reported in recent automatic NPC GTV segmentation using either CT or MRI modality.

CONCLUSION

We developed a fully automated multi-modal deep-learning model for NPC GTV segmentation. The developed model can segment the NPC GTV in high accuracy. With further optimization and validation, this automated model has potential to standardize the NPC GTV segmentation and significantly decrease the workload of radiation oncologists in clinical practice.

Deep Learning for Automatic Prediction of Lymph Node Station Metastasis in Esophageal Cancer Patients from Contrast-Enhanced CT

PURPOSE/OBJECTIVE(S)

The diagnosis of lymph node (LN) metastasis in computed tomography (CT) is an essential yet challenging task in esophageal cancer staging and treatment planning. Although criteria (e.g., RECIST, morphological/texture features) are proposed to predict LN metastasis, the diagnostic accuracy remains low with sensitivity <50% and specificity <75%, as reported in previous studies. Deep learning (DL) has the potential to address this issue by learning from large-scale labeled data. However, due to the practical surgery procedure in lymph node dissection, it is difficult to pair the metastasis of individual LN reported in the pathology report to the LN instance found in the CT image. Hence, in this study, we first use pathology reports to determine the LNS metastasis, then develop a multiple instance deep learning (MIDL) model to predict lymph node station (LNS) metastasis.

MATERIALS/METHODS

We collected 1200 esophageal cancer patients with preoperative contrast-enhanced CT before surgery. A recently developed automatic mediastinal LNS segmentation model was first applied to segment LNS of 1 to 8 based on the IASLC protocol. For each LNS, the local CT region of interest (ROI) was cropped to generate a station-wise CT patch, where the LNS was labeled as metastatic if at least one metastatic LN was indicated in the pathology report. Using the station-wise CT patch and LNS label, we train a 3D MIDL model, MobileNetV3, to predict LNS metastasis. To better provide the LN position priors in MIDL, LN instances (with a short axis >4mm) were also segmented using an automatic LN detection algorithm and were added to the MIDL model as an auxiliary input. Five-fold cross-validation was conducted to evaluate the MIDL performance.

RESULTS

The MIDL model's performance is summarized in Table 1. The MIDL model incorporating an additional LN instance mask demonstrated a superior overall AUC of 0.7539, surpassing the model without the LN mask input by 2.93%. The specificity was evaluated at a threshold resulting in a recall of 0.7, and the best model outperformed the CT input model in terms of specificity by 2.11%. This highlights the value of including the LN position prior to the MIDL model. Notably, when a threshold was set to result in a specificity of 75%, the best MIDL model demonstrated a significantly higher recall compared to the previously reported clinical diagnostic recall (39.7% vs. 63.21%).

CONCLUSION

We developed a MIDL classification model to predict LNS metastasis using CT scans of 1200 patients. Our findings suggest that the MIDL model can substantially improve LNS metastasis prediction and has the potential to play an essential role in cancer staging, treatment planning, and prognostic analysis.

Effects of Microhabitat Temperature Variations on the Gut Microbiotas of Free-Living Hibernating Animals

Variations in ambient temperature (Ta) may significantly influence the gut microbiotas of ectothermic and endothermic animals, affecting fitness. It remains unclear, however, whether temperature fluctuations affect the gut microbial communities of hibernating animals during torpor. To investigate temperature-induced changes in the gut microbiota during hibernation under entirely natural conditions, we took advantage of two adjacent but distinct populations of the least horseshoe bat (Rhinolophus pusillus), which inhabit sites with a similar summer Ta but a different winter Ta. Using 16S rRNA gene high-throughput sequencing, we estimated differences in gut microbial diversity and composition between the hibernating (winter) and active (summer) R. pusillus populations at both sites. During the active period, gut microbiotas did not differ significantly between the two populations, probably due to the similar Tas. However, during hibernation, a higher Ta was associated with decreased α-diversity in the gut microbiome. During hibernation, temperature variation did not significantly affect the relative abundance of Proteobacteria, the dominant phylum at both sites, but marked site-specific differences were detected in the relative abundances of Firmicutes, Actinobacteria, and Tenericutes. In total, 74 amplicon sequence variants (ASVs) were significantly differentially abundant between the hibernating and active bat guts across the two sites; most of these ASVs were associated with the cooler site, and many belonged to pathogenic genera, suggesting that lower ambient temperatures during hibernation may increase the risk of pathogen proliferation in the host gut. Our findings help to clarify the mechanisms underlying the gut microbiota-driven adaptation of hibernating mammals to temperature changes. IMPORTANCE Temperature variations affect gut microbiome diversity and structure in both ectothermic and endothermic animals. Here, we aimed to characterize temperature-induced changes in the gut microbiotas of adjacent natural populations of the least horseshoe bat (Rhinolophus pusillus) which hibernate at different ambient temperatures. We found that the ambient temperature significantly affected the α-diversity, but not the β-diversity, of the gut microbiota. Bats hibernating at cooler temperatures experienced more drastic shifts in gut microbiome structure, with consequent effects on energy-related metabolic pathways. Our results provide novel insights into the effects of ambient temperature on the gut microbiotas of hibernating animals.

Comparison of higher-order aberrations between implantable collamer lens V4c implantation and simulated spectacle correction in patients with high myopia

PURPOSE

To investigate the differences in higher-order aberrations between non-toric or toric implantable collamer lens (ICL or TICL) V4c implantation and simulated spectacle correction.

METHODS

Patients with high myopia who underwent ICL/TICL V4c implantation were enrolled. The "total no defocus" pattern of iTrace aberrometry to simulate the condition of spectacle correction was measured before ICL/TICL implantation, and higher-order aberrations in this condition were compared to those 3 months after surgery. Related factors with changes in coma were comprehensively analyzed.

RESULTS

A total of 89 right eyes of 89 patients were included. Compared to simulated spectacle correction, total-eye coma (P<0.0001 ICL, P<0.0001 TICL) and internal coma (P<0.0001 ICL, P<0.001 TICL) decreased in the ICL- and TICL-treated groups after surgery. Total-eye secondary astigmatism (P<0.0001 ICL, P=0.007 TICL) and internal secondary astigmatism (P<0.0001 ICL, P=0.009 TICL) were also decreased in both groups postoperatively. Spherical error showed positive correlations with variation in total-eye coma (r=0.37, P=0.004 ICL; r=0.56, P=0.001 TICL) and internal coma (r=0.30, P=0.02 ICL and r=0.45, P=0.01 TICL). Axial length revealed negative correlations with changes in total-eye coma (r=-0.45, P<0.001 ICL; r=-0.39, P=0.03 TICL) and internal coma (r=-0.28, P=0.03 ICL and r=-0.42, P=0.02 TICL).

CONCLUSIONS

Both ICL- and TICL-treated groups demonstrated a decrease in coma and secondary astigmatism after 3 months, postoperatively. ICL/TICL may confer a compensatory effect on coma aberration and secondary astigmatism. Patients with a higher myopia achieved a greater improvement in coma and may benefit more from ICL/TICL implantation than from spectacle correction implantation than from spectacle correction.

Epigenetic changes between the active and torpid states in the greater horseshoe bat (Rhinolophus ferrumequinum)

Dynamic epigenetic changes during hibernation occur in some hibernating rodents, but these changes are poorly understood in hibernating bats. Populations of the greater horseshoe bat (Rhinolophus ferrumequinum) in north China hibernate and provide an opportunity to study how epigenetic markers and modifiers differ in the active and torpid states of a chiropteran. We used fluorescence-labeled methylation-sensitive amplified polymorphism (F-MSAP) and qRT-PCR techniques to determine changes in the global DNA methylation levels and mRNA expression levels of methylation-related proteins. These included DNA methyltransferase (DNMTs), methyl-CpG-binding proteins (MBPs, including MBDs, UHRFs, and zinc-finger protein family) in active and torpid R. ferrumequinum. In the torpid state, both the relative global methylation and the relative mRNA expression levels of some DNMTs and MBPs, including dnmt3b and zbtb4, increased significantly compared to the expression levels of these in the active state. These changes may involve methylation or assist in regulation of a particular subset of genes according to hibernation status. This indicates that epigenetic mechanisms may exist and facilitate the hibernation process of R. ferrumequinum.

DOCK4 regulates ghrelin production in gastric X/A-like cells

PURPOSE

Ghrelin, a gastric hormone, provides a hunger signal to the central nervous system to stimulate food intake. Ghrelin also modulates neuroinflammatory and apoptotic processes. Dedicator of cytokinesis 4 (DOCK4), a guanine nucleotide exchange factor (GEF), is involved in the regulation of neuronal polarization and axon regeneration. However, the effect of DOCK4 on ghrelin production has not been explored.

METHODS

The expression of DOCK4 in human and mouse stomach was examined by immunohistochemical staining. The synthesis and secretion of ghrelin in Dock4 null mice were evaluated by real-time quantitative PCR, Western blot and ELISA. The effects of DOCK4 on ghrelin production in mHypoE-42 cells were measured by real-time quantitative PCR and Western blot.

RESULTS

We showed that DOCK4 was expressed in both human and mouse gastric ghrelin cells. The mRNA and protein levels of gastric ghrelin, as well as ghrelin secretion, were remarkably diminished in Dock4 null mice. Furthermore, we showed that overexpression of Dock4 significantly stimulated ghrelin expression, while siRNA knockdown of endogenous Dock4 resulted in a marked decrease of ghrelin in mHypoE-N42 cells.

CONCLUSIONS

Our results identify DOCK4 as a critical regulator for ghrelin production in gastric X/A-like cells.

Optogenetic Control of Background Fluorescence Reduction for CRISPR-Based Genome Imaging

The CRISPR/dCas9 system has become an essential tool for live-cell imaging of genomic loci, but it has limited applications in imaging low-/non-repetitive genomic loci due to the strong nuclear background noise emerging from many untargeted fluorescent modules. Here, we propose an optogenetically controlled background fluorescence reduction strategy that combines the CRISPR-SunTag system with a light-inducible nuclear export tag (LEXY). Utilizing the SunTag system, multiple copies of LEXY-tagged sfGFP were recruited to the C-terminal dCas9, recognizing the target genomic loci. As the nuclear export sequence at the C-terminal LEXY could be exposed to pulsed blue light irradiation, the untargeted nuclear labeling modules were light controllably transferred to the cytoplasm. Consequently, genomic loci containing as few as nine copies of repeats were clearly visualized, and a significant increase in the signal-to-noise ratio was achieved. This simple and controllable method is expected to have a wide range of applications in cell biology.

Rheumatoid arthritis and the risk of major cardiometabolic diseases: a Mendelian randomization study

OBJECTIVE

Rheumatoid arthritis (RA) is suggested to be implicated in the development of cardiometabolic diseases. We conducted a Mendelian randomization (MR) study to assess potential causality for associations of RA with the risk of cardiometabolic diseases, including type 2 diabetes (T2D), coronary artery disease (CAD), and ischaemic stroke.

METHOD

Seventy independent single-nucleotide polymorphisms (SNPs) associated with RA were identified as instrumental variables from a genome-wide association study (GWAS) of 58 284 European subjects. Summary-level data for the associations of the 70 genetic variants with T2D, CAD, and ischaemic stroke were taken from three GWASs with a total of 1 529 131 participants. Inverse-variance weighted (IVW) MR was used in the main analyses.

RESULTS

The main IVW MR analysis showed that genetically determined RA was associated with higher risks of T2D [odds ratio (OR): 1.04, 95% confidence interval (CI) 1.02-1.05; p < 0.001] and CAD (OR: 1.02, 95% CI 1.00-1.03; p = 0.012), but not ischaemic stroke (OR: 1.00, 95% CI 0.99-1.02; p = 0.961). Sensitivity analyses with multiple MR methods confirmed these associations. MR-Egger regression showed no evidence of pleiotropy in the association between genetically determined RA and the risk of T2D, CAD, and ischaemic stroke. Leave-one-out sensitivity analysis showed that the association between genetically determined RA and the risk of T2D, CAD, and ischaemic stroke was not driven by any individual SNP.

CONCLUSION

Genetically determined RA was associated with increased risks of T2D and CAD, suggesting that RA plays a crucial role in the pathogenesis of T2D and CAD.

Cold Spray: Over 30 Years of Development Toward a Hot Future

Cold Spray (CS) is a deposition process, part of the thermal spray family. In this method, powder particles are accelerated at supersonic speed within a nozzle; impacts against a substrate material triggers a complex process, ultimately leading to consolidation and bonding. CS, in its modern form, has been around for approximately 30 years and has undergone through exciting and unprecedented developmental steps. In this article, we have summarized the key inventions and sub-inventions which pioneered the innovation aspect to the process that is known today, and the key breakthroughs related to the processing of materials CS is currently mastering. CS has not followed a liner path since its invention, but an evolution more similar to a hype cycle: high initial growth of expectations, followed by a decrease in interest and a renewed thrust pushed by a number of demonstrated industrial applications. The process interest is expected to continue (gently) to grow, alongside with further development of equipment and feedstock materials specific for CS processing. A number of current applications have been identified the areas that the process is likely to be the most disruptive in the medium-long term future have been laid down.

A bibliometric analysis of primary ovarian insufficiency from 2010 to 2020

OBJECTIVE

This study aimed to carry out a bibliometric analysis of primary ovarian insufficiency (POI) from 2010 to 2020 and to reveal the research status and hotspots in the future.

METHOD

A total of 3087 articles and reviews related to POI published from 2010 to 2020 retrieved from the Web of Science Core Collection were used for bibliometric analysis. CiteSpace and VOSviewer were adopted to analyze countries and regions, organizations, authors, journals, keywords and co-cited references.

RESULTS

The number of publications about POI increased year by year. The USA produced the largest number of publications and the most influence in this field. The main research directions of POI can be roughly divided into four aspects according to the analysis of keywords and co-cited references: genetic research of POI; stem cell therapy for patients with POI; prediction of ovarian function; and fertility preservation of cancer patients. Genetic research and stem cell therapy may become research hotspots in the future.

CONCLUSION

This study might be the first bibliometric study to analyze publications of POI from multiple indicators, in order to provide new opinions for the research trends and possible hotspots of POI.

[The effects of robotic-assisted versus laparoscopic-assisted radical right hemicolectomy on short-term outcome and long-term prognosis based on propensity score matching]

Objective: To compare the short-term and long-term outcomes between robotic-assisted and laparoscopic-assisted radical right hemicolectomy in patients with adenocarcinoma of the right colon. Methods: Retrospective review of a prospectively collected database identified 288 right colon cancer patients who underwent either robotic-assisted (n=57) or laparoscopic-assisted right hemicolectomy (n=231) between October 2014 and October 2020 at Department of Gastrointestinal Surgery, the Affiliated Hospital of Qingdao University. There were 161 males and 127 females, aging (60.3±12.8) years (range: 17 to 86 years). After propensity score matching as 1∶4 between robotic-assisted and laparoscopic-assisted right hemicolectomy, there were 56 cases in robotic group and 176 cases in laparoscipic group. Perioperative outcomes and overall survival were compared between the two groups using t test, Wilcoxon rank sum test, χ² test, Fisher exact test, Kaplan-Meier method and Log-rank test, respectively. Results: The total operative time was similar between the robotic and laparoscopic group ((206.9±60.7) minutes vs. (219.9±56.3) minutes, t=-1.477, P=0.141). Intraoperative bleeding was less in the robotic group (50 (20) ml vs. 50 (50) ml, Z=-4.591, P<0.01), while the number of lymph nodes retrieved was significantly higher (36.0±10.0 vs. 29.0±10.1, t=4.491, P<0.01). Patients in robotic group experienced significantly shorter hospital stay, shorter time to first flatus, and defecation (t: -2.888, -2.946, -2.328, all P<0.05). Moreover, the overall peri-operative complication rate was similar between robotic and laparoscopic group (17.9% vs. 22.7%, χ²=0.596,P=0.465). The 3-year overall survival were 92.9% and 87.9% respectively and the 3-year disease-free survival rates were 83.1% and 82.6% with no statistical significance between the robotic and laparoscopic group (P>0.05). Conclusions: Compared to laparoscopic-assisted right hemicolectomy, robot-assisted right hemicolectomy could improve some short-term clinical outcomes. The two procedures are both achieving comparable survival.

[Regulatory effect of small nuclear ribonucleoprotein-associated protein B on proliferation and metastasis of liver cancer cells]

Objective: To study the expression and effect of small nuclear ribonucleoprotein-associated protein B (SNRPB) on proliferation and metastasis of liver cancer tissues and cells. Methods: The bioinformatics database starBase v3.0 and GEPIA were used to analyze the expression of SNRPB in liver cancer tissue and normal liver tissue, as well as the survival and prognosis of liver cancer patients. The expression of SNRPB mRNA and protein in liver cancer cell lines were analyzed by qRT-PCR and Western blot. RNA interference technique (siRNA) was used to determine SNRPB protein expression down-regulation. The proliferation effect on hepatocellular carcinoma cells was observed by MTT assay. Transwell invasion and migration assay was used to detect the changes in the metastatic ability of liver cancer cells after SNRPB down-regulation. Western blot was used to detect the changes of epithelial mesenchymal transition (EMT) markers in liver cancer cells after down-regulation of SNRPB expression. Data were compared between two groups and multiple groups using t-test and analysis of variance. Results: The expression of SNRPB was significantly higher in liver cancer tissue than normal liver tissue, and its expression level was correlated with the prognosis of liver cancer patients. Compared with the immortalized hepatocyte LO(2), the expression of SNRPB was significantly increased in the liver cancer cells (P < 0.01). siRNA-SNRPB had significantly inhibited the expression of SNRPB mRNA and protein in liver cancer cells. MTT results showed that the absorbance value was lower in SNRPB knockdown group than negative control group, and the difference at 96 h after transfection was most significant (P < 0.01). Transwell assay results showed that compared with the negative control group, the SNRPB knockdown group (MHCC-97H: 121.27 ± 8.12 vs. 46.38 ± 7.54; Huh7: 126.50 ± 6.98 vs. 41.10 ± 8.01) invasion and migration (MHCC-97H: 125.20 ± 4.77 vs. 43.18 ± 7.32; Huh7: 132.22 ± 8.21 vs. 38.00 ± 6.78) ability was significantly reduced (P < 0.01) in liver cancer cells. Western blot showed that the expression level of epithelial phenotype marker E-cadherin was decreased after down-regulation of SNRPB, while the expression levels of mesenchymal phenotype markers N-cadherin and vimentin was increased, suggesting that down-regulation of SNRPB inhibited EMT in liver cancer cells. Conclusion: SNRPB expression is significantly increased in liver cancer tissues and cells, and it is involved in regulating the proliferation, metastasis and EMT of liver cancer cells.

The Association between Dietary Magnesium Intake and Telomere Length in Adults with Hypertension

BACKGROUND

Dietary micronutrients are significantly associated with telomere length, as shown in multiple studies. However, no study has investigated the association between magnesium intake and telomere length in adults with hypertension.

METHODS

Participants were included from the National Health and Nutrition Examination Survey (NHANES) in 1999-2000 and 2001-2002. Dietary magnesium intake was assessed using the 24 - hour recall method and the telomere length of leukocytes was measured using polymerase chain reaction (PCR). A multivariate regression model was then used to assess the association between dietary magnesium intake and telomere length in adults with hypertension.

RESULTS

Our final analysis included 2199 hypertensive adults (46.79% males) with a mean dietary magnesium intake of 254.82±133.47 mg/day. Linear regression, adjusted for race, sex, age, smoking, uric acid, and other variables, showed that every 1 mg increase in dietary magnesium intake was associated with a 0.20 (95% CI: 0.01, 0.39, p = 0.043) longer telomere length in all participants. In the ≥45 years age group, there was a statistically significant association between the telomere length and dietary magnesium (95% CI: 0.16, 0.63, p <0.001).

CONCLUSIONS

This study suggests that increased magnesium intake is associated with a longer telomere length in hypertensive adults, especially in those ≥45 years of age. However, further research is needed to determine a causal relationship.

[Effect of perioperative accelerated rehabilitation management program for children with congenital spinal deformity]

Objective: To explore the perioperative therapeutic effect of enhanced recovery after surgery (ERAS) in children with congenital spinal deformity and summarize the clinical experience. Methods: Fifty-nine pediatric patients with congenital spinal deformities admitted to Beijing Children's Hospital from May 2020 to January 2021 were included in this study, and all patients underwent posterior spinal osteotomy orthopedic implant fusion with internal fixation. There were 22 males and 37 females, aged (7.4±4.1) years. Patients were divided into ERAS group (n=29) and control group (n=30) according to the management model. Patients in the ERAS group were managed with an accelerated recovery management model during the perioperative period, which mainly included: high protein diet, shortened fasting time, optimized anesthesia protocol, and multimodal analgesia. Patients in the control group received the traditional perioperative management model. The indexes of surgery, diet, pain score and laboratory tests were compared between the two groups. Results: All patients completed the surgery successfully. The mean temperature and pain scores of patients in the ERAS group were lower than those in the control group at 3 days postoperatively (P<0.05). The time to exhaustion and defecation in the ERAS group was (1.0±0.8) d and (2.5±0.9) d postoperatively, both significantly earlier than those in the control group ((3.4±0.8) d and (4.0±1.1) d) (both P<0.05). C-reactive protein was 38(8,46) mg/L in patients of the ERAS group on the day 3 postoperatively, which was significantly lower than that in the control group 47(22,93) mg/L (P=0.023). The hemoglobin level on postoperative day 3 was (110.7±9.6) g/L in the ERAS group, which was significantly higher than that in the control group ((104.5±11.4) g/L) (P=0.029). Postoperative complications occurred in 8(27.6%) and 9(30.0%) patients in the ERAS and control groups, respectively (P=1.000), with mild abdominal pain and bloating being the most common complications in both groups, most of which were not treated specifically. Conclusion: ERAS is a safe and effective perioperative management mode for children with congenital spinal deformity. Compared with the traditional method, it can significantly improve the treatment efficiency and deserve clinical application.

Single-cell transcriptome analysis yields new insights into the pathogenic mechanisms and possible genetic etiology of cardiomyopathies

Background

Inherited cardiomyopathies (CM) represent a clinically heterogeneous group of primary cardiac muscle disorders with a strong genetic underpinning. Recent rapid genomic advances have led to the identification of numerous disease-causing genes for both non-syndromic (nsCM) and syndromic (sCM) cardiomyopathies. This has greatly facilitated molecular genetic testing, thus enabling accurate disease diagnosis needed for the practice of precision medicine and the optimization of patient outcome. However, many cardiomyopathies remain unexplained with the known genes and dominant genetic model of disease.

Purpose

To reassess the genetic features of known CM genes as a strategy to recover novel candidate CM genes.

Methods

Known hypertrophic CM (HCM), dilated CM (DCM) and pediatric CM genes were curated from the literature and from 23 commercial CM diagnostic panels. They were classified as non-syndromic and syndromic, and further annotated using two constraint metrics, the missense Z score and pLI score obtained from the GnomAD database. Publicly available mouse (n=6) and human (n=3) single-cell RNA (scRNA) datasets were downloaded and cardiomyocyte specific differentially expressed genes (DEGs) (fold change &gt;0.1; adjusted P&lt;0.0001) were recovered. Genes identified as DEGs in at least 4 mouse or 3 human scRNA datasets were recovered as nsCM candidate genes.

Results

Analyses of 9 scRNA datasets showed the majority of known nsCM genes are cardiomyocyte specific (Fig. 1a-b). nsCM and sCM genes have distinct expression and genetic profile. nsCM genes are associated with higher heart expression and lower loss intolerance (Fig. 1c). In contrast, syndromic CM genes mostly showed lower expression with high loss intolerance, consistent with their higher clinical impact. However, interestingly some of the nsCM genes (MYLK2, TMPO and KLF10) show low or even no detectable expression in mouse and human cardiac cells. Using the scRNA data, we assessed cellular expression of genes in the 23 commercial CM diagnostic panels. This analysis showed some of the CM genes with high cardiomyocytes expression have low coverage on the current commercial CM panels (Fig. 1d). Using human and mouse scRNA data, we recovered 224 mouse and 157 human nsCM candidate genes. MTUS2 (microtubule-associated tumor suppressor candidate 2) was identified as a strong nsCM candidate gene supported by evidence from both mouse and human studies (Fig. 1e-f).

Conclusions

Our analysis showed many of the nsCM genes have differential cardiomyocyte expression with low loss intolerance, while the reverse was observed for many sCM genes. We propose increasing commercial panel coverage of cardiomyocytes-specific expressed genes may help increase disease diagnostic yield. Additionally, novel candidate genes uncovered trained on cardiomyocyte expression profile may help accelerate elucidation of unsolved cardiomyopathy cases.

Funding Acknowledgement

Type of funding sources: None.

P–501 Deep in the Maze: The psychosocial trajectory and decision making of Women with recurrent implantation failure of IVF

Study question

To understand the psychosocial trajectory of Chinese women who have experienced recurrent implantation failure (RIF) of IVF and their decision making accordingly.

Summary answer

Chinese women experience despair, doubt, and disorientation along with the cumulative failure cycles of IVF, and stick to IVF as the ultimate option.

What is known already

Recurrent implantation failure, the absence of implantation after repeated embryo transfers is a stressful event for people undergoing treatment for infertility. Numerous researches have focused on the psychological wellness of women undertaking IVF, but pay less attention to the subgroup who have undergone repeated failures. Current studies have shown that women after repeated unsuccessful IVF might endure anxiety, depression, and other psychosocial distress; however, the feelings brought by the different times of failure are unlike, and these experiences will affect their treatment decisions accordingly, which is rarely studied.

Study design, size, duration

Semi-structured interview was adopted with sixteen Chinese women from March 2020 to July 2020. The interview lasted 90 minutes. A follow-up survey was conducted three months after the interview. Driven by grounded theory, data is analyzed by thematic analysis.

Participants/materials, setting, methods

Convenience sampling was used to recruit female participants who have failed to achieve clinical pregnancy after two consecutive cycles of fresh or frozen IVF embryo transfers with a cumulative number of transferred embryos of four or more cleavage-stage embryos or two or more blastocysts. Chinese-speaking women who were undertaking IVF treatment in the reproductive center of hospital in Shenzhen City were recruited by pamphlets and doctors’ referral.

Main results and the role of chance

Chinese women with recurrent implantation failures experience the following psychosocial trajectory during the cumulative failure cycles of IVF: despair, doubt, and disorientation. Despair usually comes after the first failure: the high expectation for success rates makes the initial failure exceptionally shocking and desperate. Huge distress brings two kinds of decisions: start a new IVF cycle quickly to welcome the positive results in the imagination, or wait for a period of time to avoid the pain of failure again. Doubt usually appears after the second failure. In addition to doubting the health function of their body, recurrent failure makes the patients particularly doubt the efficacy of IVF and doctors’ clinical judgment. Some patients would do ‘hospital shopping’ and consider change clinics. Disorientation can be seen in patients who have experienced more than three cycles of failure. Past experience and meaning cannot help them understand and solve the current dilemma. The inherent concept of fertility continues to strengthen their belief of having a baby as ultimate goal. The follow-up survey found that most women still choose to continue IVF treatment after repeated failure. They are like being in the maze of fertility, wandering for a long time but unable to get out.

Limitations, reasons for caution

Several limitations are identified: self-selection bias due to convenience sampling; narrow sampling approach may limits the generalizability; the exclusion of men may ignore the marital interdependence during the infertility treatment.

Wider implications of the findings: Patients who have experienced recurrent implantation failure demand promising intervention during and after infertility treatment. The findings demonstrate the need for both supportive and implication counseling to facilitate them cope with the psychosocial distress, and make value-based decision making, so as to enhance their self-agency.

Trial registration number

Not applicable

[Regulatory effects of LIM kinase 1 on the proliferation and metastasis of hepatocellular carcinoma cells]

Objective: To study LIM kinase 1 (LIMK1) expressional condition, and its regulatory effects on the proliferation and metastasis of hepatocellular carcinoma cells and tissues. Methods: The online database starBase v3.0 and GEPIA were used to analyze the LIMK1 expression in hepatocellular carcinoma cells and normal liver tissues, and then the relevant survival analysis was performed. LIMK1 expression in hepatocellular carcinoma cell line was analyzed by Western blot. Hep3B and Huh7 cells were transiently transfected after LIMK1 protein expression was down-regulated by small interfering RNA (siRNA). LIMK1 effects on the proliferation of Hep3B and Huh7 cells were observed by MTT assay and colony formation assay. Transwell assay was used to detect the change in metastatic ability of hepatocellular carcinoma cell after the down-regulation of LIMK1 expression. Western blot was used to detect the changes of related indexes in the process of epithelial mesenchymal transition after the down-regulation of LIMK1 expression. Data were analyzed by one-way ANOVA. Results: The expression level of LIMK1 in liver cancer tissues was significantly higher than that of normal liver tissues, and was related with prognosis (P ​< 0.01). Furthermore, LIMK1 expression in HCC cell lines was significantly higher than that of immortalized liver L02 cells (P < 0.05). Functional correlated experiment showed that the proliferation and metastatic ability of liver cancer cells were significantly inhibited after LIMK1 expression down-regulation (P < 0.05). Simultaneously, LIMK1 was also involved in the process of epithelial-mesenchymal transition. Conclusion: LIMK1 was overexpressed in HCC tissues and cells, and may regulate the proliferation and metastasis of HCC cells and participate in epithelial-mesenchymal transition process.

POS0417 EXOGENOUS CXCL5 RESTORES ENDOGENOUS BLOOD-TISSUE CHEMOKINE GRADIENT TO IMPROVE SURVIVAL IN MURINE LUPUS

Background:

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease that is potentially fatal. There is an unmet need to improve current therapies. In patients with SLE, we observed that serum CXCL5 levels were significantly lower than healthy control subjects and negatively correlated with disease activity(1-9).

Objectives:

The aim of this study is to elucidate the effect of supplemental serum CXCL5 in abrogating the pathological processes of SLE.

Methods:

Ten doses of exogenous CXCL5 (3µg/kg) was administered to 16-week-old Faslpr mice weekly by intravenous injection. Mice were monitored for 10 weeks. Splenic immune profile was measured by flow cytometry. Circulating cytokine and immunoglobulin profile were detected by Luminex technology. Renal function was evaluated by urinary spot albumin creatinine ratio. In situ renal immune cell infiltration and complement 3 deposition were detected by Haematoxylin and Eosin (H&E) and immunohistochemistry staining. The molecular pathways involved were examined by RNA sequencing.

Results:

In Faslpr mice, intravenous administration of exogenous CXCL5 significantly improved mouse survival with concomitant reduction of autoantibody secretion, proteinuria, complement 3 deposition, neutrophil infiltration and lupus nephritis classes. Through evaluating the changes of immune profile, cytokine profile and molecular pathways, we found that intravenous CXCL5 reduced inflammation via an orchestral effect of regulating neutrophil trafficking and modulating helper T cell-mediated immune response. Pharmacokinetic and real-time Polymerase Chain Reaction studies further demonstrated that this orchestration was triggered by a cascade reaction - restoring vascular under-expressed CXCL5 by an exogenous stimulation, re-establishing the normal serum levels of endogenous CXCL5 and reverting the CXCL5 chemokine gradient between inflamed tissues and blood circulation.

Conclusion:

Managing the dysregulation of CXCL5 by exogenous supplement may provide a new option for SLE therapy.

References:

[1]Dufies M, Grytsai O, Ronco C, et al. New CXCR1/CXCR2 inhibitors represent an effective treatment for kidney or head and neck cancers sensitive or refractory to reference treatments. Theranostics. 2019;9(18):5332-5346. doi:10.7150/thno.34681

[2]Yildirim K, Colak E, Aktimur R, et al. Clinical Value of CXCL5 for Determining of Colorectal Cancer. Asian Pac J Cancer Prev. Sep 26 2018;19(9):2481-2484. doi:10.22034/apjcp.2018.19.9.2481

[3]Wu K, Yu S, Liu Q, Bai X, Zheng X. The clinical significance of CXCL5 in non-small cell lung cancer. Onco Targets Ther. 2017;10:5561-5573. doi:10.2147/ott.s148772

[4]Zhao J, Ou B, Han D, et al. Tumor-derived CXCL5 promotes human colorectal cancer metastasis through activation of the ERK/Elk-1/Snail and AKT/GSK3beta/beta-catenin pathways. Mol Cancer. Mar 29 2017;16(1):70. doi:10.1186/s12943-017-0629-4

[5]Han KQ, Han H, He XQ, et al. Chemokine CXCL1 may serve as a potential molecular target for hepatocellular carcinoma. Cancer Med. Oct 2016;5(10):2861-2871. doi:10.1002/cam4.843

[6]Pappa CA, Tsirakis G, Kanellou P, et al. Monitoring serum levels ELR+ CXC chemokines and the relationship between microvessel density and angiogenic growth factors in multiple myeloma. Cytokine. Dec 2011;56(3):616-20. doi:10.1016/j.cyto.2011.08.034

[7]Zhang L, Li H, Ge C, et al. CXCL3 contributes to CD133(+) CSCs maintenance and forms a positive feedback regulation loop with CD133 in HCC via Erk1/2 phosphorylation. Sci Rep. Jun 3 2016;6:27426. doi:10.1038/srep27426

[8]Matsubara J, Honda K, Ono M, et al. Reduced plasma level of CXC chemokine ligand 7 in patients with pancreatic cancer. Cancer Epidemiol Biomarkers Prev. Jan 2011;20(1):160-71. doi:10.1158/1055- 9965.epi-10-0397

[9]Ma Y, Ren Y, Dai ZJ, Wu CJ, Ji YH, Xu J. IL-6, IL-8 and TNF-alpha levels correlate with disease stage in breast cancer patients. Adv Clin Exp Med. May-Jun 2017;26(3):421-426. doi:10.17219/acem/62120

Disclosure of Interests:

None declared

Identification of a mitogen-activated protein kinase kinase (AccMKK4) from Apis cerana cerana and its involvement in various stress responses

The mitogen-activated protein kinase (MAPK) cascade pathway is a ubiquitous signal transduction pathway in eukaryotes that regulates a variety of immune responses. This study accomplished the first isolation of an AccMKK4 gene from Apis cerana cerana and explored its function. Yeast two-hybrid experiments proved that AccMKK4 can interact with Accp38b, and the silencing of AccMKK4 in honeybees downregulated the expression level of Accp38b, which suggests that AccMKK4 might participate in the oxidative stress response through the p38 MAPK pathway. Tissue-specific expression levels of AccMKK4 analysis showed that AccMKK4 in the thorax, particularly muscle tissue, was higher than that in other tissues. The qRT-PCR results from different conditions demonstrated that AccMKK4 responds to various environmental stresses. After AccMKK4 silencing, the transcription level of some antioxidant genes and the activity of antioxidant-related enzymes are reduced, which indicated that AccMKK4 plays an important role in resistance against oxidative stress caused by external stimuli. In summary, our findings indicate that AccMKK4 probably plays an indispensable role in the response of honeybees to environmental stress and might aid for further research on the role of the MAPK cascade pathway in the antioxidant defence mechanisms of insects.

Social calls influence the foraging behavior in wild big-footed myotis

BACKGROUND

Why a variety of social animals emit foraging-associated calls during group foraging remains an open question. These vocalizations may be used to recruit conspecifics to food patches (i.e. food advertisement hypothesis) or defend food resources against competitors (food defence hypothesis), presumably depending on food availability. Insectivorous bats rely heavily on vocalizations for navigation, foraging, and social interactions. In this study, we used free-ranging big-footed myotis (Myotis macrodactylus Temminck, 1840) to test whether social calls produced in a foraging context serve to advertise food patches or to ward off food competitors. Using a combination of acoustic recordings, playback experiments with adult females and dietary monitoring (light trapping and DNA metabarcoding techniques), we investigated the relationship between insect availability and social vocalizations in foraging bats.

RESULTS

The big-footed myotis uttered low-frequency social calls composed of 7 syllable types during foraging interactions. Although the dietary composition of bats varied across different sampling periods, Diptera, Lepidoptera, and Trichoptera were the most common prey consumed. The number of social vocalizations was primarily predicted by insect abundance, insect species composition, and echolocation vocalizations from conspecifics. The number of conspecific echolocation pulses tended to decrease following the emission of most social calls. Feeding bats consistently decreased foraging attempts and food consumption during playbacks of social calls with distinctive structures compared to control trials. The duration of flight decreased 1.29-1.96 fold in the presence of social calls versus controls.

CONCLUSIONS

These results support the food defence hypothesis, suggesting that foraging bats employ social calls to engage in intraspecific food competition. This study provides correlative evidence for the role of insect abundance and diversity in influencing the emission of social calls in insectivorous bats. Our findings add to the current knowledge of the function of social calls in echolocating bats.

Illuminating single genomic loci in live cells by reducing nuclear background fluorescence

The tagging of genomic loci in living cells provides visual evidence for the study of genomic spatial organization and gene interaction. CRISPR/dCas9 (clustered regularly interspaced short palindromic repeats/deactivated Cas9) labeling system labels genes through binding of the dCas9/sgRNA/fluorescent protein complex to repeat sequences in the target genomic loci. However, the existence of numerous fluorescent proteins in the nucleus usually causes a high background fluorescent readout. This study aims to limit the number of fluorescent modules entering the nucleus by redesigning the current CRISPR/dCas9-SunTag labeling system consisting of dCas9-SunTag-NLS (target module) and scFv-sfGFP-NLS (signal module). We removed the nuclear location sequence (NLS) of the signal module and inserted two copies of EGFP into the signal module. The ratio of the fluorescent intensity of the nucleus to that of the cytoplasm (N/C ratio) was decreased by 71%, and the ratio of the signal to the background (S/B ratio) was increased by 1.6 times. The system can stably label randomly selected genomic loci with as few as 9 repeat sequences.

[Predictive value of N-terminal B-type natriuretic peptide on outcome of elderly hospitalized non-heart failure patients]

Objective: To investigate the predictive value of N-terminal type B natriuretic peptide（NT-proBNP) on the prognosis of elderly hospitalized patients without heart failure（non-heart failure). Method: Elderly patients aged 65 years or older, who were admitted to Beijing Hospital from September 2018 to February 2019, were enrolled in this study. Patients with clinical diagnosis of heart failure or left ventricular ejection fraction（LVEF)<50% were excluded. The patients were divided into 2 groups based on the serum NT-proBNP level: low NT-proBNP group （<125 ng/L) and high NT-proBNP group（≥125 ng/L). Patients were followed up at 3, 6, and 12 months after enrollment, and the major adverse events were recorded. The composite endpoint events included all-cause mortality, readmission or Emergency Department visits. Cardiovascular events include death, readmission or emergency room treatment due to cardiogenic shock, myocardial infarction, angina pectoris, arrhythmia, heart failure or stroke/transient ischemic attack. Results: A total of 600 elderly patients with non-heart failure were included in the analysis. The average age was （74.9±6.5) years, including 304（50.7%) males. The median follow-up time was 344（265, 359) days. One hundred and seventy-eight（29.7%) composite endpoint events were recorded during the follow-up, 19（3.2%) patients died, and 12（2.0%) patients were lost to follow-up. There were 286(47.7%) cases in low NT-proBNP group and 314 cases（52.3%) in high NT-proBNP group. Patients were older, prevalence of atrial fibrillation and myocardial infarction was higher; MMSE scores and ADL scores, albumin and creatinine clearance rate were lower in high NT-proBNP group than in low NT-proBNP group（all P<0.05). At 1-year follow-up, the incidence of composite endpoint events was significantly higher in high NT-proBNP group than in low NT-proBNP group（33.4%（105/314) vs. 24.8%（71/286), P = 0.02). Cardiovascular events were more common in high NT-proBNP group than in low NT-proBNP group（17.5%（55/314) vs. 8.4%（24/286), P = 0.001). Kaplan-Meier survival analysis showed both composite endpoint events（Log-rank P=0.016) and cardiovascular events（Log-rank P=0.001) were higher in high NT-proBNP group than in low NT-proBNP group. All-cause mortality was also significantly higher in highNT-proBNP group than in lowNT-proBNP group（4.8%（15/314) vs. 1.4%（4/286), P = 0.020), and Kaplan-Meier survival analysis demonstrated borderline statistical significance（Log-rank P = 0.052). Cox proportional hazard regression analysis showed that after adjusting for age, sex, creatinine clearance rate, myocardial infarction, and atrial fibrillation, NT-proBNP remained as an independent risk factor for composite endpoint events（HR=1.376，95%CI 1.049-1.806, P=0.021), and cardiovascular events（HR=1.777, 95%CI 1.185-2.664, P=0.005), but not for all-cause mortality（P=0.206). Conclusions: NT-proBNP level at admission has important predictive value on rehospitalization and cardiovascular events for hospitalized elderly non-heart failure patients. NT-proBNP examination is helpful for risk stratification in this patient cohort.

[Application of pump-controlled retrograde trial off in weaning from veno-arterial extracorporeal membrane oxygenation in adult patients]

Objective: To Summarize the experience of pump-controlled retrograde trial off (PCRTO) in the process of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) withdrawal in adult patients. Methods: Adult patients who received ECMO assistance in Intensive Care Unit for Cardiac Surgery from March to July 2019 were collected. According to our strategies, PCRTO was used if the patients can wean from VA-ECMO and hemodynamic indexes were recorded during the process. The statistics data was collected, including the 48 hours survival rate, ECMO re-assistance rate, thrombus complications, Intensive Care Unit (ICU) stay time and hospital stay time after weaning from VA-ECMO. The patients who failed in the test were continued to be assisted by ECMO. Results: There were 46 patients assisted by VA-ECMO in our center. In total, 21 adults who met the offline test standard underwent 26 PCRTOs, including 10 male adults (47.6%), with an age of 65 (55, 68) years old. Eighteen adults passed the withdrawal test. No new thrombus was found in the arteriovenous ultrasound of the lower extremity after weaning from ECMO, and no pulmonary embolism was found in the chest X-ray. The success rate of weaning from ECMO was 69.23%(18/26). The D-dimer decreased [584(348,2 107)μg/L vs 1 440(631,2 916)μg/L, P=0.014] and the left ventricular ejection fraction (LVEF) increased (51.4%±8.5% vs 46.9%±10.6%, P=0.013) on the next day after weaning. There were significant differences in heart rate (HR), central venous pressure (CVP), oxygenation index and lactate (Lac) during the PCRTO in the group which involved the cases of the 8 failed experiments (all P<0.05). Compared with the failure group, there were significant differences in age, blood flow rate, CVP before the test, HR, pulse oxygen saturation(SpO(2)), CVP, Lac and oxygenation index after the test, and the variations of SpO(2), CVP and Lac. Conclusion: PCRTO is a simple, reversible, safe and effective weaning method. It can be used in the process of VA-ECMO withdrawal in adult patients.

[Predictors for perioperative blood loss in pediatric patients with congenital scoliosis]

Objective: To identify predictors of massive blood loss after posterior hemivertebra resection for patients with congenital scoliosis. Methods: The data of 106 children with congenital scoliosis were collected from June 2017 to June 2019 in Beijing Children's Hospital. All the cases received posterior hemivertebra resection and internal fixation. The blood volume was estimated by weight and height. The visible blood loss was recorded according to medical record, and the hidden blood loss was calculated by OSTHEO formula. Perioperative information including age, gender, height, weight, Cobb and kyphosis angle, level fused, number of screws, operative time, and laboratory examinations was collected. Then multivariable linear regression was performed to determine the independent risk factors of blood loss. Results: All the surgeries were completed successfully. The mean age of the children was (7.3±2.3) years and the operative time was (162±56) min. The mean fused levels were 3 and the correction rate for deformity was 78.4%. The amount of blood loss was (568±208) ml which accounted for 42.3% of total blood volume. The visible and hidden blood loss was (334±193) ml and (234±199) ml, respectively, and which accounted for 58.8% and 41.2% of total blood loss. Multivariable linear regression analysis indicated that age, preoperative Cobb angle, the time of surgery and the number of fused levels were independent risk factors of total blood loss. Preoperative Cobb angle ≥40°, spinal fusion ≥4 levels and operative duration ≥140 min indicated more blood loss (all P<0.05). Conclusions: The perioperative blood loss of congenital scoliosis is massive with a high percentage of hidden blood loss. The patients with severe deformity, more fused levels and increased operative time brings higher risk of massive blood loss.

Hypomethylation of Notch1 DNA is associated with the occurrence of uveitis

Uveitis is a serious intra-ocular inflammatory disease that can lead to visual impairment even blindness worldwide. Notch signaling can regulate the differentiation of naive CD4⁺ T cells, influencing the development of uveitis. DNA methylation is closely related to the autoimmune diseases. In this study, we measured the Notch1 DNA methylation level, determined the Notch1 and related DNA methylases mRNA expression and evaluated the ratio of T helper type 17 regulatory T cell (Th17/T_reg ) in peripheral blood mononuclear cells (PBMCs) from uveitis patients and normal control subjects; we also tested the levels of relevant inflammatory cytokines in serum from the participants. Results indicated that compared with those in normal control individuals, the expression of ten-eleven translocation 2 (TET2) and Notch1 mRNA is elevated in uveitis patients, whereas the methylation level in Notch1 DNA promotor region [-842 ~ -646 base pairs (bp)] is down-regulated, and is unrelated to anatomical location. Moreover, the Th17/T_reg ratio is up-regulated in PBMCs from uveitis patients, accompanied by the elevated levels of proinflammatory cytokines [e.g. interleukin (IL)-2, IL-6, IL-17 and interferon (IFN)-γ] in serum from uveitis patients. These findings suggest that the over-expression of TET2 DNA demethylase may lead to hypomethylation of Notch1, activate the Notch1 signaling, induce naive CD4⁺ T cells to differentiate theTh17 subset and thus disturb the balance of the Th17/T_reg ratio in uveitis patients. Overall, hypomethylation of Notch1 DNA is closely associated with the occurrence of uveitis. Our study preliminarily reveals the underlying mechanism for the occurrence of uveitis related to the hypomethylation of Notch1 DNA, providing a novel therapeutic strategy against uveitis in clinical practice.

AB0128 CXCL5 DAMPENS INFLAMMATION IN THE PRE-CLINICAL MODEL OF SYSTEMIC LUPUS ERYTHEMATOSUS VIA THE ORCHESTRAL EFFECT OF REGULATING NEUTROPHIL TRAFFICKING AND SUPPRESSING HELPER T CELL-MEDIATED IMMUNE RESPONSE

Background:

Patients with systemic lupus erythematosus (SLE) suffer from severe morbidity and mortality1-4, either from the disease itself or from side effects of immunosuppression5. Discovery of novel effective therapies with less toxicity is an urgent need.

Objectives:

The aim of this study is to elucidate the therapeutic potential and working mechanism of cytokine CXCL5 in lupus mice.

Methods:

Treatment with CXCL5, bone marrow (BM)-MSCs, standard of care (SOC) with combination of methylprednisolone and cyclophosphamide was given to 16-week-old Faslprmice. Mice were monitored for 10 weeks. Splenic immune cell subsets were measured by flow cytometry. Circulating cytokine and immunoglobulin were detected by Luminex technology. Renal function was evaluated by urinary spot albumin creatinine ratio. In situ renal immune cell infiltration and complement 3 deposition were detected by Haematoxylin and Eosin (H&E) staining and immunohistochemistry.

Results:

CXCL5 demonstrated consistent and potent immunosuppressive capacity in suppressing SLE with reduced autoantibody secretion, lymphoproliferation and preserved kidney function. With further exploration, we proved that CXCL5 reduced the proliferation of helper T cells (TH1 and TH2) in thein vitrofunctional assay. When we administrated CXCL5 to lupus mice, it promoted the proliferation of regulatory T cells and reduced the proliferation of TH17 cells, macrophages and neutrophils. Multiple proinflammatory cytokines including IL-2, IL-6, IL-12, IL-17A, KC/CXCL1, MIP-1β/CCL4 and TNF-α were also reduced. When combined with SOC, CXCL5 boosted its therapeutic effect and reduced the relevant indices of disease activity. When we correlated the effect of four different treatment groups (CXCL5, BM-MSCs, SOC, and CXCL5 plus SOC) on mice survival and target cell changes, we found that TH17 cells were the key effector cells involved in the pathogenesis of SLE.

Conclusion:

These findings demonstrated that CXCL5 dampens inflammation in the pre-clinical model of systemic lupus erythematosus via the orchestral effect of regulating neutrophil trafficking and suppressing helper T cell-mediated immune response. Administrating exogenous CXCL5 might be an attractive option to treat patients with lupus.

References:

[1]Ji S, Guo Q, Han Y, Tan G, Luo Y, Zeng F. Mesenchymal stem cell transplantation inhibits abnormal activation of Akt/GSK3beta signaling pathway in T cells from systemic lupus erythematosus mice.Cell Physiol Biochem.2012;29(5-6):705-712.

[2]Peng SL. Altered T and B lymphocyte signaling pathways in lupus.Autoimmun Rev.2009;8(3):179-183.

[3]Ferucci ED, Johnston JM, Gaddy JR, et al. Prevalence and incidence of systemic lupus erythematosus in a population-based registry of American Indian and Alaska Native people, 2007-2009.Arthritis Rheumatol.2014;66(9):2494-2502.

[4]Jakes RW, Bae SC, Louthrenoo W, Mok CC, Navarra SV, Kwon N. Systematic review of the epidemiology of systemic lupus erythematosus in the Asia-Pacific region: prevalence, incidence, clinical features, and mortality.Arthritis Care Res (Hoboken).2012;64(2):159-168.

[5]Sattwika PD, Mustafa R, Paramaiswari A, Herningtyas EH. Stem cells for lupus nephritis: a concise review of current knowledge.Lupus.2018;27(12):1881-1897.

Acknowledgments:

The work was supported by SMART II Centre Grant (NMRC/CG/M011/2017_SGH) and SingHealth Foundation (SHF/FG638P/2016).

Disclosure of Interests:

None declared

FRI0328 PROFILING OF THE IMMUNE COMPARTMENT IN THE TISSUE ENVIRONMENT OF PSORIATIC ARTHRITIS USING RNASEQ

Background:

Psoriasis is a chronic inflammatory disease of the skin with a reported prevalence of 0.09-11.4% of the population (1). 1 in 4 psoriasis patients also have psoriatic arthritis (PsA) (2), with additional joint involvement that can be associated with significant morbidity. Despite its relative commonness, the aetiology of psoriasis is not well understood, and there is no cure for this disease. Additionally, up to 30% of PsA patients with active disease are recalcitrant to treatment. Thus it remains a prerogative to understand the immune mechanisms contributing to the development of the disease in order to inform strategies for novel therapies.

Objectives:

Our aim was to identify perturbations in local tissue immune networks that could contribute to the pathology of psoriasis and psoriatic arthritis. We hypothesise that psoriasis is driven by a disrupted tissue microenvironment, which then provides cues to a susceptible peripheral immune system to drive pathology. Thus as the first part of our study, we investigated the transcriptional profiles of normal and lesional skin.

Methods:

Skin punch biopsies were obtained from both lesional and morphologically normal skin of 4 PsA patients with active disease. CD45+ cells were isolated using magnetic enrichment for RNA purification and subsequent RNAseq. Differently expressed genes (DEG) were identified and pathway analysis performed using the integrated Differential Expression and Pathway (iDEP) analysis tool. Gene set enrichment analysis was performed using GSEA.

Results:

Transcriptomic analyses of skin revealed that lesional skin, compared to non-lesional sites, was enhanced for expression of genes associated with immune processes (including genes such as such asIL17A,FCN1, andCTLA4) anti-microbial responses (such asDEF4BAandS100A8) and immune cell chemotaxis (notablyCXCL13andSELPLG), suggesting a possible inflammatory response to skin microbiota. Interestingly, lesional skin showed a deficiency in expression of genes associated with tRNA metabolic processes (includingAARS,YARS, and other aminoacyl tRNA synthetases), suggesting a possible defect in protein translation. Similarly, pathway analysis revealed an enrichment in humoral immune response pathways in PsA lesional skin, and a comparative deficiency in RNA metabolic pathways.

Conclusion:

Our transcriptional approach provides a comprehensive overview of localised immunity in psoriasis and predicts intimate interactions with the peripheral immune system. Further studies are ongoing to uncover cell types involved, as well as parallels at other disease sites (joints). These findings will facilitate the identification of novel targets for treatment of PsA.

References:

[1]World Health Organization (2016).Global report on psoriasis. [Online] (https://apps.who.int/iris/bitstream/handle/10665/204417/9789241565189_eng.pdf.psoriasis;jsessionid=54912784D28C9F36ECCD45471AC5775B?sequence=1,accessed 24 January 2020)

[2]Alinaghi F., Calov M., Kristensen L.E., Gladman D.D, Coates L.C., Julien D., Gottlieb A.B., Gisondi P., Wu J.J., Thyssen J.P., Egeberg A. (2019) Prevalence of psoriatic arthritis in patients with psoriasis: A systemic review and meta-analysis of observational and clinical studies.Journal of the American Academy of Dermatology.,80(1), 251-265.

Disclosure of Interests:

Gladys Ang: None declared, Pavanish Kumar: None declared, Dianyan Guo: None declared, Ahmad Lajam: None declared, Warren Fong Consultant of: Abbvie, Janssen, Novartis, Speakers bureau: Abbvie, Janssen, Novartis, Ying Ying Leung Speakers bureau: Novartis, Janssen, Eli Lilly, Salvatore Albani: None declared

Necrosulfonamide (NSA) protects intervertebral disc degeneration via necroptosis and apoptosis inhibition

OBJECTIVE

Previous studies have shown that nucleus pulposus (NP) cell death plays an extremely important role in the progress of intervertebral disc degeneration (IVDD). This research aimed to investigate the protective effect of the MLKL inhibitor necrosulfonamide (NSA) on human NP cells.

PATIENTS AND METHODS

We collected human NP tissues from the patients undergoing disc herniation operations and isolated NP cell from the samples. IL-1β (10 ng/ml) was used to establish a NP cells degenerated model. We analyzed the expression of caspase 3, caspase 8, RIPK1, RIPK 3, and MLKL in different degree of degenerate disc tissues. Cell viability was analyzed by the Cell Counting Kit-8 (CCK-8) assay. The expression levels of collagen Ⅱ, β-galactosidase (β-gal), caspase 3, caspase 8, RIPK1, RIPK 3, and MLKL, several inflammatory and anti-oxidant enzymes of different NP cell treat groups were detected by Western blotting, immunofluorescence staining, or RT-PCR. Flow cytometry was used to measure the ROS level and cell apoptosis.

RESULTS

The data showed that expression of caspase 3, caspase 8, RIPK1, RIPK 3, and MLKL markedly increased in severely degenerated disc tissues. IL-1β promoted the cell death of NP cells, while NSA could reverse the effects of IL-1β. We found that NAS increased the antioxidant SOD1, SOD2, CAT, and GPX3 expression and suppressed oxidative stress in the disc. Moreover, MMP3, MMP10, IL-6, and TNF-α were significantly suppressed by the NSA.

CONCLUSIONS

These results suggest that NSA prevented NP degradation via inhibiting apoptosis and necroptosis of NP cells. Besides, the protective function of antagonizing cell death may owe to the inflammation and oxidative stress suppression.

Ambient temperature correlates with geographic variation in body size of least horseshoe bats

Geographic variation in body size is common within many animal species. The causes of this pattern, however, remain largely unexplored in most vertebrate groups. Bats are widely distributed globally owing to their ability of powered flight. Most bat species encounter a variety of climatic conditions across their distribution range, making them an ideal taxon for the study of ecogeographic patterns in body size. Here, we used adult least horseshoe bats, Rhinolophus pusillus, to test whether geographic variation in body size was determined by heat conservation, heat dissipation, climatic seasonality, or primary productivity. We measured body mass and head-body length for 246 adult bats from 12 allopatric colonies in China. We quantified the ecological conditions inhabited by each colony, including mean maximum temperature of the warmest month, mean minimum temperature of the coldest month, temperature seasonality, precipitation seasonality, and annual net primary productivity (ANPP). Body mass and head-body length, 2 of the most reliable indicators of body size, exhibited marked differences between colonies. After controlling for spatial autocorrelation, the mean minimum temperature of the coldest month explained most of the variation in body size among colonies, regardless of sex. The mean maximum temperature, climatic seasonality, and ANPP had limited power in predicting body size of males or females in comparison with mean minimum temperature. These results support the heat conservation hypothesis and suggest adaptive responses of body size to cold climates in cave-dwelling bats.

Plasma exchange combining with plasma bilirubin adsorption effectively removes toxic substances and improves liver functions of hepatic failure patients

OBJECTIVE

Hepatic failure (HF) is a kind of complex disease characterizing with liver dysfunction and a few clinical complications. Artificial liver support system (ALSS) has been applied to HF patients to improve dysfunctional liver in recent years. This study aims to evaluate therapeutic effects of ALSS approaches, including plasma exchange (PE), plasma diafiltration (PDF) and plasma bilirubin adsorption (PBA), on liver function of HF patients.

PATIENTS AND METHODS

This study is a retrospective analysis involving 516 patients diagnosed as HF between February 2014 and February 2015. Patients were randomly divided into PE, PDF, PE plus PBA, and PDF plus PBA group. Meanwhile, single-drug group and combined-drug group were also divided. The liver functions, capability of removing toxic substances and coagulation functions were evaluated both pre-treatment and post-treatment. The side effects and hospital improvement rate were also observed post-treatment.

RESULTS

Hospital improvement rate achieves to 69.6%. TBIL levels and MELD scores were significantly decreased post-treatment compared to pre-treatment (p<0.05). PTA values were significantly increased post-treatment compared to pre-treatment (p<0.05). Reduction value in PE+PBA group was significantly higher compared to PE and PDF group (p=0.002, 0.002, respectively). MELD scores were significantly decreased post-treatment compared to pre-treatment in each group (p<0.05). Combined-drug treatment is superior to single-drug treatment for removing toxic substances and improving liver functions. PE treatment, PDF treatment and PE+PBA treatment induced more side effects compared to PDF+PBA treatment.

CONCLUSIONS

PE combining with PBA plays a better role in removing toxic substances, improving liver functions of HF patients.

Social vocalizations of big-footed myotis (Myotis macrodactylus) during foraging

Acoustic signals play a crucial role in transmitting information and maintaining social stability in gregarious animals, especially in echolocating bats, which rely primarily on biological sonar for navigating in the dark. In the context of foraging without relying on tactile, visual or olfactory cues, acoustic signals convey information not only on food but also on ownership and defense of resources. However, studies on such information remain fragmentary. In the present study, we aim to document the social vocal repertoire of Myotis macrodactylus at natural foraging sites. Multiple acoustic analyses and spectrographic classification revealed a rich foraging vocal repertoire comprising 6 simple syllables and 2 composites. Discriminant function analyses associated with a subset-validation procedure provided an optimal method to spectrographically classify all recorded sounds into different syllable types. Multidimensional scaling of median values of multiple parameters further confirmed notable differences among these syllables in a 3-D space. In addition, Euclidean distance analysis showed that there were some spectral similarities between specific social vocal syllables and feeding buzzes, which implied a potential jamming role. Altogether, the data indicate that bats at foraging sites under natural conditions used variant social vocalizations with different functions in addition to echolocation calls, providing supporting evidence for further work on the function and vocal mechanisms of acoustic communication in mammals.