A nonsense mutation in the CUL3 gene in a Chinese patient with autism spectrum disorder and epilepsy: A case report

RATIONALE

CUL3 (OMIM: 603136) encodes cullin-3, a core component of ubiquitin E3 ligase. Existing medical research suggests that CUL3 mutations are closely related to neurodevelopmental disorder with or without autism or seizures (neurodevelopmental disorder with autism and seizures, OMIM: 619239). However, the number of published case reports of autism spectrum disorder due to CUL3 gene mutations is limited.

PATIENT CONCERN

A four-year-old Chinese girl presented with generalized epilepsy, and then exhibited developmental regression, including loss of her speaking ability, eye contact aversion, and stereotyped behavior.

DIAGNOSES

Whole-exome sequencing identified a nonsense mutation in the CUL3 gene, being c.2065A > T (p.Lys689*); no previous similar case was reported. The final diagnosis was autism, epilepsy, and motor growth retardation.

INTERVENTION

In order to improve quality of life of the patient, she was provided with exercise rehabilitation training and autism behavioral guidance therapy for 3 months.

OUTCOMES

The patient's exercise capacity had improved, and improvements in autism symptoms were not obvious.

LESSONS

For clinicians, patients with developmental regression accompanied with concurrent epilepsy and autism spectrum disorder should be advised that relevant genetic tests are necessary to clarify the diagnosis.

[Drug resistance and genomic characteristics of Salmonella enterica serovar London from clinical and food sources in Hangzhou City from 2017 to 2021]

Objective: To analyze the drug resistance and genomic characteristics of Salmonella enterica serovar London isolated from clinical and food sources in Hangzhou City from 2017 to 2021. Methods: A total of 91 Salmonella enterica serovar London strains isolated from Hangzhou City from 2017 to 2021 were analyzed for drug susceptibility, pulsed field gel electrophoresis (PFGE) typing and whole genome sequencing. Multilocus sequence typing (MLST), core genome multilocus sequence typing (cgMLST) and detection of drug resistance genes were performed by using the sequencing data. Phylogenetic analysis was conducted to compare the 91 genomes from Hangzhou City with 347 genomes from public databases. Results: No significant difference in the drug resistance rate was observed between clinical strains and food strains to 18 drugs in Hangzhou City(all P>0.05), and the multidrug resistance (MDR) rate was 75.8% (69/91). Most strains were resistant to 7 drug classes simultaneously. One strain was resistant to Polymyxin E as well as positive for mcr-1.1, and 50.5% (46/91) of the strains were resistant to Azithromycin and were positive for mph(A). All 91 Salmonella enterica serovar London strains were ST155, which were subdivided into 44 molecular types by PFGE and 82 types by cgMLST. Phylogenetic analysis showed that most strains from Hangzhou City (83/91) were clustered together, and a small number of human isolates from Europe, North America and pork isolates from Hubei and Shenzhen were mixed in the cluster. Other strains from Hangzhou City (8/91) were closely related to strains from Europe, America and Southeast Asia. Strains isolated from pork were the most closely related to clinical strains. Conclusion: The epidemic of Salmonella enterica serovar London in Hangzhou City is mainly caused by the spread of ST155 strains, which is mainly transmitted locally. At the same time, cross-region transmission to Europe, North America, Southeast Asia, and other provinces and cities in China may also occur. There is no significant difference in the drug resistance rate between clinical strains and food strains, and a high level of MDR is found in the strains. Clinical infection of Salmonella enterica serovar London may be closely related to pork consumption in Hangzhou City.

Artificial intelligence for detection of intracranial haemorrhage on head computed tomography scans: diagnostic accuracy in Hong Kong

INTRODUCTION

The use of artificial intelligence (AI) to identify acute intracranial haemorrhage (ICH) on computed tomography (CT) scans may facilitate initial imaging interpretation in the accident and emergency department. However, AI model construction requires a large amount of annotated data for training, and validation with real-world data has been limited. We developed an algorithm using an open-access dataset of CT slices, then assessed its utility in clinical practice by validating its performance on CT scans from our institution.

METHODS

Using a publicly available international dataset of >750 000 expert-labelled CT slices, we developed an AI model which determines ICH probability for each CT scan and nominates five potential ICH-positive CT slices for review. We validated the model using retrospective data from 1372 non-contrast head CT scans (84 [6.1%] with ICH) collected at our institution.

RESULTS

The model achieved an area under the curve of 0.842 (95% confidence interval=0.791-0.894; P<0.001) for scan-based detection of ICH. A pre-specified probability threshold of ≥50% for the presence of ICH yielded 78.6% accuracy, 73% sensitivity, 79% specificity, 18.6% positive predictive value, and 97.8% negative predictive value. There were 62 true-positive scans and 22 false-negative scans, which could be reduced to six false-negative scans by manual review of model-nominated CT slices.

CONCLUSION

Our model exhibited good accuracy in the CT scan-based detection of ICH, considering the low prevalence of ICH in Hong Kong. Model refinement to allow direct localisation of ICH will facilitate the use of AI solutions in clinical practice.

[Resting heart rate correlates with major adverse cardiovascular and cerebrovascular events in patients with post-myocardial infarction ventricular aneurysms: a retrospective cohort study]

OBJECTIVE

To analyze the association of resting heart rate (RHR) with the prognosis of patients with post-infarction ventricular aneurysms.

METHODS

We retrospectively analyzed the clinical data of 227 patients with post-infarction ventricular aneurysms admitted to our hospital during 2017-2019. The endpoint event was the occurrence of any major adverse cardiovascular and cerebrovascular events (MACCEs) during the follow-up for 24 months. According to RHR measurements, the patients were divided into 3 groups with baseline RHR < 10%, 10%-90%, and >90%. The Cox proportional risk model and restricted cubic spline (RCS) model were used to analyze the effect of RHR on MACCEs.

RESULTS

During the 24-month followup, 90 patients (39.6%) experienced MACCEs. The fully adjusted RCS curves showed a nonlinear "U" shaped correlation between RHR and the occurrence of MACCEs. In the fully adjusted model, the risk of MACCEs increased by 3.01-fold (Hazard ratio [HR]=4.01, 95% CI: 2.07-7.76, P < 0.001) in patients with RHR>90%, as compared with patients with RHR of 10%-90%. In patients with RHR in 1-9th percentile, 10th-90th percentile and 91st-100th percentile, the incidences of MACCEs were 39.1%, 36.6% and 66.7% (P=0.027), the incidences of ventricular tachycardia/ventricular fibrillation (VT/VF) were 17.4%, 2.7% and 4.8% (P=0.005), and the incidences of readmission for heart failure were 8.7%, 26.8% and 42.9% (P=0.036), respectively.

CONCLUSION

Continuous monitoring and management of heart rate range may provide guidance for prognosis prediction in patients with post-infarction ventricular aneurysms.

RESOLVE-based radiomics in cervical cancer: improved image quality means better feature reproducibility?

AIM

To compare the reproducibility of apparent diffusion coefficient (ADC)-based radiomic features between readout-segmented echo-planar diffusion-weighted imaging (RESOLVE) and single-shot echo-planar diffusion-weighted imaging (SS-EPI DWI) in cervical cancer.

MATERIALS AND METHODS

The RESOLVE and SS-EPI DWI images of 36 patients with histopathologically confirmed cervical cancer were collected retrospectively. Two observers independently delineated the whole tumour on RESOLVE and SS-EPI DWI, and then copied them to the corresponding ADC maps. Shape, first-order, and texture features were extracted from ADC maps in the original and filtered (Laplacian of Gaussian [LoG] and wavelet) images. Thereafter, 1,316 features were generated in each RESOLVE and SS-EPI DWI, respectively. The reproducibility of radiomic features was assessed using intraclass correlation coefficient (ICC).

RESULTS

In the original images, RESOLVE showed 92.86%, 66.67%, and 86.67% of features with excellent reproducibility in shape, first-order, and texture features, while SS-EPI DWI showed 85.71%, 72.22%, and 60% of features with excellent reproducibility, respectively. In the LoG and wavelet filtered images, RESOLVE had 56.77% and 65.32% of features with excellent reproducibility and SS-EPI DWI had 44.95% and 61.96% of features with excellent reproducibility, respectively.

CONCLUSION

Compared with SS-EPI DWI, the feature reproducibility of RESOLVE was better in cervical cancer, especially for texture features. The filtered images cannot improve the feature reproducibility compared with the original images for both SS-EPI DWI and RESOLVE.

HISMD: A Novel Immune Subtyping System for HNSCC

Immune subtyping is an important way to reveal immune heterogeneity, which may contribute to the diversity of the progression and treatment in head and neck squamous cell carcinoma (HNSCC). However, reported immune subtypes mainly focus on levels of immune infiltration and are mostly based on a mono-omics profile. This study aimed to identify a comprehensive immune subtype for HNSCC via multi-omics clustering and build a novel subtype prediction system for clinical application. Data were obtained from The Cancer Genome Atlas database and our independent multicenter cohort. Multi-omics clustering was performed to identify 3 clusters of 499 patients in The Cancer Genome Atlas based on immune-related gene expression and somatic mutations. The immune characteristics and biological features of the obtained clusters were revealed by bioinformatics, and 3 immune subtypes were identified: 1) adaptive immune activation subtype predominantly enriched in T cells, 2) innate immune activation subtype predominantly enriched in macrophages, and 3) immune desert subtype. Subsequently, the clinical implications of each subtype were analyzed per clinical epidemiology. We found that adaptive immune activation showed better survival outcomes and had a similar response to chemotherapy with innate immune activation, whereas immune desert might be relatively resistant to chemotherapy. Moreover, a subtype prediction system was developed by deep learning with whole slide images and named HISMD: HNSCC Immune Subtypes via Multi-omics and Deep Learning. We endowed HISMD with interpretability through image-based key feature extraction. The clinical implications, biological significances, and predictive stability of HISMD were successfully verified by using our independent multicenter cohort data set. In summary, this study revealed the immune heterogeneity of HNSCC and obtained a novel, highly accurate, and interpretable immune subtyping prediction system. For clinical implementation in the future, additional validation and utility studies are warranted.

MGF360-12L of ASFV-SY18 is an immune-evasion protein that inhibits host type I IFN, NF-κB, and JAK/STAT pathways

African swine fever virus (ASFV) causes feverous and hemorrhagic disease of domestic pigs and European wild boars with high mortality, yet no commercial vaccine is currently available. Several ASFV strains with natural deletion or gene-targeted knockout of multiple MGF360 and MGF505 genes are attenuated in vitro and in vivo, and can offer full protection against homologous challenge. However, the mechanisms underlying the protection are not fully understood. This study aims to investigate the effects of MGF360-12L of ASFV-SY18 on the cGAS-STING signaling pathway and explore the potential mechanisms. We identified that ASFV-SY18 MGF360-12L could inhibit cGAS-STING, TBK1, or IRF3-5D-stimulated IFN-β expression and ISRE activation. Specifically, MGF360-12L inhibits both the activation of PRD(III-I) in a dose-dependent manner, and suppresses the exogenous expression of TBK1 and IRF3-5D. MGF360-12L could block NF-κB activation induced by overexpression of cGAS-STING, TBK1, IKKβ. Downstream of the IFN-β signaling, MGF360-12L blocks the ISRE promoter activation by reducing total protein level of IRF9. Moreover, MGF360-12L protein can inhibit IFN-β-mediated antiviral effects. In conclusion, our findings suggest that MGF360-12L is a multifunctional immune-evasion protein that inhibits both the expression and effect of IFN-β, which could partially explain the attenuation of relevant gene-deleted ASFV strains, and shed light on the development of efficient ASFV live attenuated vaccines in the future.

Genome-wide identification and expression analysis of SlRR genes in response to abiotic stress in tomato

The cytokinin two-component signal transduction system (TCS) is involved in many biological processes, including hormone signal transduction and plant growth regulation. Although cytokinin TCS has been well characterized in Arabidopsis thaliana, its role in tomato remains elusive. In this study, we characterized the diversity and function of response regulator (RR) genes, a critical component of TCS, in tomato. In total, we identified 31 RR genes in the tomato genome. These SlRR genes were classified into three subgroups (type-A, type-B and type-C). Various stress-responsive cis-elements were present in the tomato RR gene promoters. Their expression responses under pesticide treatment were evaluated by transcriptome analysis. Their expression under heat, cold, ABA, salinity and NaHCO₃ treatments was further investigated by qRT-PCR and complemented with the available transcription data under these treatments. Specifically, SlRR13 expression was significantly upregulated under salinity, drought, cold and pesticide stress and was downregulated under ABA treatment. SlRR23 expression was induced under salt treatment, while the transcription level of SlRR1 was increased under cold and decreased under salt stress. We also found that GATA transcription factors played a significant role in the regulation of SlRR genes. Based on our results, tomato SlRR genes are involved in responses to abiotic stress in tomato and could be implemented in molecular breeding approaches to increase resistance of tomato to environmental stresses.

Asperosaponin VI Protects Against Bone Loss Due to Hindlimb Unloading in Skeletally Growing Mice Through Regulating Microbial Dysbiosis Altering the 5-HT Pathway

Osteoporosis is a complex multifactorial disease that can lead to an increased risk of fracture. However, selective and effective osteoporosis drugs are still lacking. We showed that Asperosaponin VI (AVI) has the implications to be further developed as an alternative supplement for the prevention and treatment of bone loss. AVI has been found to have beneficial effects on metabolic diseases such as bone loss, obesity, and atherosclerosis. Our study was designed to determine the effect and mechanism of action of AVI against bone loss through regulating microbial dysbiosis. A hindlimb unloading mouse model was established to determine the effect of AVI on bone microarchitecture, gut microbiota, and serum metabolites. Eighteen female C57BL/6 J mice were divided into three groups: control, hindlimb unloading with vehicle (HLU), and hindlimb unloading treated with AVI (HLU-AVI, 200 mg/kg/day). AVI was administrated orally for 4 weeks. The results demonstrated that AVI improved the bone microstructure by reversing the decrease in bone volume fraction and trabecular number, and the increase in trabecular separation and structure model index of cancellous bone in hindlimb suspension mice. The results of 16sRNA gene sequencing suggested that the therapeutic effect of AVI on bone loss may be achieved through it regulating the gut microbiota, especially certain specific microorganisms. Combined with the analysis of ELISA, immunohistochemistry, and serum metabolome results, it could be speculated that AVI played an important role in adjusting the balance of bone metabolism by influencing specific flora such as Clostridium and its metabolites to regulate the 5-hydroxytryptophan pathway. The study explored the novel mechanism of AVI against osteoporosis, and has implications for the further development of AVI as an alternative supplement for the prevention and treatment of bone loss.

Association between sarcopenia and prediabetes among non-elderly US adults

AIM

To explore the specific association between sarcopenia and prediabetes based on large population samples.

METHODS

A total of 16,116 U.S. adults aged 20-59 with dual energy X-ray absorptiometry (DXA) was identified from the National Health and Nutrition Examination Surveys (NHANES). Sarcopenia was defined according to appendicular skeletal muscle mass (ASM) adjusted for body mass index (BMI). Multivariable binary logistic regression models were used to ascertain odds ratios (ORs) for developing prediabetes. Stratified analyses were also performed.

RESULTS

Prevalence of prediabetes was higher in the sarcopenia group (n = 1055) compared with the non-sarcopenia group (n = 15,061) (45.50% vs 28.74%, P < 0.001). Sarcopenia was strongly associated with an increased risk of prediabetes after full adjustment (OR = 1.21, 95CI%: 1.05, 1.39, P = 0.009). In the stratified analysis, this association remained significant independent of obesity, triglycerides, and low-density lipoprotein cholesterol levels. When sarcopenia subjects combined with obesity especially central obesity, the risk of prediabetes was the highest (OR = 2.63, 95CI%: 2.22, 3.11, P < 0.001). Furthermore, a greater proportion of any of impaired glucose tolerance (IGT) individuals was observed in the sarcopenia group compared to the non-sarcopenia group among prediabetes population (41.72% vs 24.06%, P < 0.001).

CONCLUSIONS

Sarcopenia was positively associated with prevalent prediabetes especially IGT in the non-elderly. Moreover, synergistic interactions between the sarcopenia and obesity could greatly increase the risk of prediabetes.

[Formation of professor Mao Xiejun's thoughts on stomatological education]

Professor Mao Xiejun wrote a report about dental education of China in 1935. From 1948 to 1950, he published three articles containing the educational idea of "developing dentistry into stomatology". When he served as the director of the Faculty of Dentistry of Peking University Medical School in July 1950, he proposed to rename the Faculty of Dentistry into the Faculty of Stomatology,which were approved by the Ministry of Health and the Ministry of Education of the People's Republic of China in one month. The Chinese Medical Association established the Society of Stomatology the next year. Later, dentistry was successively changed into stomatology, and medical content was integrated into dental education, which was of great significance and far-reaching influence. During the developments of the thought of stomatological education in China, Professor Mao Xiejun evidently played a pivotal role. In this paper, the formation process of the thoughts of stomatological education related to professor Mao Xiejun's contribution is elucidated through studying the archives, personal letters, and historical documents, so as to enrich the researches on the history of stomatology in China and to facilitate better understanding and promoting the development of stomatology.

[Research progress on the relationship between air pollution and gestational diabetes]

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications and has serious implications for the health of mothers and their offspring. In recent years, studies have confirmed that air pollution is one of the main risk factors for diabetes, and there is increasing evidence that air pollution exposure is closely related to the occurrence of gestational diabetes. However, current studies on the association between air pollutant exposure and the incidence of gestational diabetes are inconsistent, and the window period of pollutant exposure is still unclear. Limited mechanistic studies suggest that airborne particulate matter and gaseous pollutants may affect GDM through multiple mechanisms, including inflammation, oxidative stress, disruption of adipokine secretion, and imbalance of intestinal flora. This review summarizes the relationship between air pollutant exposure and the incidence of GDM in recent years, as well as the possible molecular mechanism of the occurrence and development of GDM caused by air pollutants, in order to provide scientific basis for preventing pollutant exposure, reducing the risk of GDM, improving maternal and fetal outcomes and improving the quality of the birth population.

[Investigation on the carriage prevalence of Neisseria meningitidis in healthy population in Jiangsu Province in 2019 and 2020]

In order to investigate carriage status and serum groups distribution of Neisseria meningitidis(Nm) among healthy population in Jiangsu Province, four counties were selected as monitoring sites by random sampling method for cross-sectional study. Throat swab specimens were collected from four monitoring sites in October to November 2019 and November to December 2020 for bacterial culture and Real-time PCR detection. Chi-square test was used to compare the positive rate of Neisseria meningitidis, and multiple logistic regression model was used to analyze the influencing factors of Neisseria meningitidis carrier rate. The results showed that among 1 512 samples, 57 strains of Nm were isolated, and the carrier rate was 3.77%. Serogroup B was the dominant group (36.84%), followed by un-known serogroups (33.33%), serogroup C was the third (17.54%), serogroup W135 and serogroup A were 7.02% and 5.26%, respectively. The carriage rate (8.60%) of 15-20 years old was significantly higher than others (1.77%-3.74%)(Pearson χ²=18.211, P<0.05). Region, age and immunization history were risk factors for Neisseria meningitidis carrier rate. In summary, the Nm carrier rate of healthy population in Jiangsu Province is relatively low, which indicates that the epidemic cases will continue to be sporadic in the future. However, the prevention and control of meningococcal epidemics on campus should be strengthened, and the monitoring of neisseria meningitidis group B should be maintained as it has become the dominant epidemic strain.

Vascular epiphyte populations with higher leaf nutrient concentrations showed weaker resilience to an extreme drought in a montane cloud forest

Leaf stoichiometry can characterize plant ecological strategies and correlate with plant responses to climate change. The role of vascular epiphytes in the ecosystem processes of tropical and subtropical forest ecosystems cannot be ignored. Vascular epiphytes are very vulnerable to climate change, however, the relationship between the response of epiphytes to climate change and leaf stoichiometry is not well understood. We present data for 19 vascular epiphyte species that were collected during four consecutive censuses (in 2005, 2010, 2015, and 2020) over 15 years in a subtropical montane cloud forest. We assessed the relationships between the population dynamics and leaf stoichiometry of these vascular epiphytes. Experiencing an extreme drought, 14 of the 19 epiphyte species showed an obvious decrease in the number of individuals, and all species showed negative growth in the number of populations. Subsequently, the total number of individuals gradually recovered, increasing from 7,195 in 2010 to 10,121 in 2015, then to 13,667 in 2020. The increase in the number of vascular epiphyte individuals from 2010 to 2015 was significantly negatively correlated with leaf nitrogen and phosphorus concentration, and was significantly positively correlated with the leaf carbon-nitrogen ratio. Vascular epiphyte populations with higher leaf nutrient concentrations exhibited weaker resilience to the extreme drought, which demonstrated that a resource-conservative strategy was advantageous for the recovery of epiphyte populations. Our findings suggest that ecological stoichiometry can be a useful framework for forecasting the dynamics of vascular epiphyte populations in response to climate change.

[Research progress of acetaldehyde dehydrogenase 2 in liver diseases]

Acetaldehyde dehydrogenase 2 (ALDH2) is an important kind of aldehyde dehydrogenase in mitochondria, which has the function of eliminating acetaldehyde and other toxic aldehydes substances. Furthermore, it is abundant in liver and is closely related to the occurrence and development of a variety of liver diseases. ALDH2 genetic polymorphisms plays an important role in the occurrence of a variety of liver diseases in the human population.This paper mainly reviews the research progress of ALDH2 in liver diseases in recent years, with a view to provide theoretical basis for clinical prevention and treatment.

Pretreatment with propofol restores intestinal epithelial cells integrity disrupted by mast cell degranulation in vitro

Propofol has been shown to against intestinal reperfusion injury when treated either before or after ischemia, during which mast cell could be activated. The aim of this study was to evaluate the role of propofol in restoring the intestinal epithelial cells integrity disrupted by mast cell activation or the released tryptase after activation in vitro. We investigated the effect of: (1) tryptase on Caco-2 monolayers in the presence of PAR-2 inhibitor or propofol, (2) mast cell degranulation in a Caco-2/LAD-2 co-culture model in the presence of propofol, and (3) propofol on mast cell degranulation. Epithelial integrity was detected using transepithelial resistance (TER) and permeability to fluorescein isothiocyanate (FITC)-dextran (the apparent permeability coefficient, Papp). The expression of junctional proteins zonula occludens-1 (ZO-1/TJP1) and occludin were determined using western blot analysis and immunofluorescence microscopy. The intracellular levels of reactive oxidative species (ROS) and Ca2+ were measured using flow cytometry. Tryptase directly enhanced intestinal barrier permeability as demonstrated by significant reductions in TER, ZO-1, and occludin protein expression and concomitant increases in Papp. The intestinal barrier integrity was restored by PAR-2 inhibitor but not by propofol. Meanwhile, mast cell degranulation resulted in epithelial integrity disruption in the Caco-2/LAD-2 co-culture model, which was dramatically attenuated by propofol. Mast cell degranulation caused significant increases in intracellular ROS and Ca2+ levels, which were blocked by propofol and NAC. Propofol pretreatment can inhibit mast cell activation via ROS/Ca2+ and restore the intestinal barrier integrity induced by mast cell activation, instead of by tryptase.

[A historical review of dental schools founded by dentists in modern China]

Eight dental schools were founded by Chinese dentists during modern times (1909-1949) in China, but only one of them still works. This article analyzes the establishment processes, faculty and student trainings in some of these dental schools, combining with the social background and management system at that time, to explore the difficulties encountered by Chinese dentists in founding dental schools before 1949.

Injection of electron beams into two laser wakefields and generation of electron rings

Mutual injection of electron beams into two laser plasma wakefields was observed experimentally when driving laser pulses interfered in plasma at a small crossing angle and were slightly relatively delayed, approximately by one pulse duration. Particle-in-cell simulations revealed that the mutual injection was sensitive to the spatial overlap of the laser pulses, which therefore could be used to control the mutual injection. The dual synchronized, femtosecond electron beams are potentially useful for pump-probe experiments in ultrafast science. In addition, out-of-axis ring-shaped electron beams were detected in both experiments and simulations.

[Occurrence of live-born twins with birth weight-discordance and its relationship to the adverse birth outcomes]

Objective: To investigate the occurrence of live-born twins with birth weight-discordance and its relationship to adverse birth outcomes. Methods: A retrospective analysis was performed on 4 011 pairs of live-born twins in the Third Affiliated Hospital of Guangzhou Medical University from January 2011 to December 2020. Based on the birth-weight discordance (∆BW, ∆BW=(birth-weight_big-birth-weight_small)/birth-weight_big×100%)), twins were divided into 4 groups, including ∆BW≤15%,>15%-20%,>20%-25%, and>25%. The differences in maternal and neonatal outcomes among 4 groups were explored. Then the correlation between ∆BW and neonatal adverse outcomes were explored. Results: The ΔBW was 9 (4, 16)% and males were accounted for 53.8% (4 315 cases) of 4 011 pairs of twins. The gestational age was (35.3±2.7) weeks at birth. There were 2 908 pairs (72.5%) of twins with ΔBW≤15%, 481 pairs (12.0%) with ΔBW>15%-20%, 281 pairs (7.0%) with ΔBW 20%-≤25%, and 341 twin pairs (8.5%) with ΔBW>25%. With ∆BW of 20% as the diagnostic cutoff, the incidence of birth weight discordance was 15.5% (622/4 011). The proportion of natural births in the ∆BW≤15% group was higher than that in the ∆BW>15%-20% group (10.5% (288/2 740) vs. 6.3% (29/463), P<0.008 3). The ∆BW>25% group had a significantly higher prevalence of maternal hypertensive disorders during pregnancy than that of the other 3 groups (25.5% (87/341) vs. 16.7% (47/281) vs.17.3% (83/480) vs. 13.8% (400/2 899), all P<0.008 3). Univariate analysis found that the ΔBW>25% group had a lower gestational age and a higher rate of preterm birth than the other groups. The rate of extremely low birth weight (ELBW) or very low birth weight (VLBW), small for gestational age (SGA), and transferring to the department of neonatology in the smaller twins were significantly different among the 4 groups (all P<0.05). Multivariate analysis showed that higher degree of birth weight discordance was all positively associated with the rate of ELBW, SGA, and transferring to the department of neonatology in smaller twin, even after adjusting maternal age and gestational hypertension, year of birth, mode of delivery, gender, and gestational age (all P<0.05). Moreover, the Mantel-Haenszel test also indicated that there were significantly low to moderate correlations between ΔBW and the unfavorable outcomes (r=0.22, 0.53, 0.21, all P<0.001, respectively). The receiver operating characteristic (ROC) curve found that adverse birth outcomes would be well predicted by birth weight-discordant when the diagnostic cut-off of ΔBW was 12%-17%, with an acceptable sensitivity (0.53-0.78) and a high specificity (0.72-0.79). Conclusions: Birth weight discordant is not uncommon in live-born twins, and is associated with adverse outcomes including ELBW, SGA, and transferring to the department of neonatology in the small twins. Besides, the risk is linearly related to the increase of ΔBW. In the future, more researches are needed to explore the underline mechanism and long-term impact of birth weight discordance, to guide the prevention and management.

[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.

[Accuracy of the China-PAR and WHO risk models in predicting the ten-year risks of cardiovascular disease in the Chinese population]

Objective: To externally validate and compare the accuracy of the China-PAR (Prediction for ASCVD Risk in China) model and the 2019 World Health Organization (WHO) cardiovascular disease risk charts for East Asian in predicting a 10-year cardiovascular disease in a general Chinese population. Methods: Participants aged 40-79 years without prior cardiovascular disease at baseline in the CHinese Electronic health Records Research in Yinzhou (CHERRY) were analyzed. The Kaplan-Meier analysis estimated the observed cardiovascular events (including non-fatal myocardial infarction, fatal coronary heart disease, and non-fatal or fatal stroke) rate within ten years. The expected risks were calculated using the WHO risk charts for East Asia (including the laboratory-based and non-laboratory-based models) and the China-PAR model. The expected-observed ratios were calculated to evaluate the overestimation or underestimation of the models in the cohort. Model accuracy was assessed by discrimination C-index, calibration χ² value, and calibration plots. Results: During a median of 7.26 years of follow-up, 13 301 cardiovascular events were identified among 225 811 participants. The C-index for the China-PAR model, WHO laboratory-based model and WHO non-laboratory-based model were 0.741 (0.735-0.747), 0.747 (0.740-0.753), and 0.739 (0.733-0.746) for men, and 0.782 (0.776-0.788), 0.789 (0.783-0.795), and 0.782 (0.776-0.787) for women, respectively. The WHO laboratory-based model and non-laboratory-based model underestimated the 10-year ASCVD risk by around 15% in women and underestimated by 0.8% and 4.4% in men, respectively. The China-PAR model underestimated the risks by 19.5% and 42.3% for men and women. Conclusions: The China-PAR and WHO models all have pretty good discriminations for 10-year cardiovascular risk assessment in this general Chinese population. However, the accuracy should be improved in the highest-risk groups, suggesting further specific models are still needed for those with the highest risk, such as patients with diabetes or older persons.

Charge Density Wave Order and Fluctuations above T_{CDW} and below Superconducting T_{c} in the Kagome Metal CsV_{3}Sb_{5}

The phase diagram of the kagome metal family AV_{3}Sb_{5} (A=K, Rb, Cs) features both superconductivity and charge density wave (CDW) instabilities, which have generated tremendous recent attention. Nonetheless, significant questions remain. In particular, the temperature evolution and demise of the CDW state has not been extensively studied, and little is known about the coexistence of the CDW with superconductivity at low temperatures. We report an x-ray scattering study of CsV_{3}Sb_{5} over a broad range of temperatures from 300 to ∼2  K, below the onset of its superconductivity at T_{c}∼2.9  K. Order parameter measurements of the 2×2×2 CDW structure show an unusual and extended linear temperature dependence onsetting at T^{*}∼160  K, much higher than the susceptibility anomaly associated with CDW order at T_{CDW}=94  K. This implies strong CDW fluctuations exist to ∼1.7×T_{CDW}. The CDW order parameter is observed to be constant from T=16 to 2 K, implying that the CDW and superconducting order coexist below T_{c}, and, at ambient pressure, any possible competition between the two order parameters is manifested at temperatures well below T_{c}, if at all. Anomalies in the temperature dependence in the lattice parameters coincide with T_{CDW} for c(T) and with T^{*} for a(T).

[Preconception reproductive health and birth outcome cohort in Chongqing: the cohort profile]

Birth cohort is an important platform to study the effect of early-life exposure on health outcome, but large cohorts to investigate the effect of preconception exposure, especially paternal exposure, on reproductive health and birth outcome are limited. The Preconception Reproductive Health and Birth Outcome Cohort (PREBIC) is a prospective birth cohort study which pays equal attention to the contribution of environmental, psychological, behavioral as well as other factors to reproductive health and adverse birth outcomes in both men and women in Chongqing, China. PREBIC started in 2019 and plans to recruit 20 800 reproductive-age couples with child-bearing willingness. Followed up was conducted to understand the conception status of the women within two years. Women in pregnancy would be visited at first, second, third trimesters and after delivery. The offspring would be monitored until 2 years old to understand the incidences of preterm birth, low birth weight, birth defects, neurodevelopmental disorders and other outcomes. Related information and biospecimen collections (including semen, peripheral blood, urine, placenta, umbilical cord, cord blood and oral swab) were scheduled in each period. By January 2022, PREBIC had recruited 8 698 participants from all 38 districts in Chongqing. The goal of PREBIC is to establish one of the largest prospective preconception birth cohorts covering both men and women, which might provide a unique insight to understand the effects of the full reproductive cycle on reproductive health and adverse outcomes, with especial emphasis on preconception exposures.

HIF-1α Stabilization Boosts Pulp Regeneration by Modulating Cell Metabolism

Stem cell-based therapeutics is a promising strategy in dental pulp regeneration. However, low cell viability after transplantation in vivo due to the ischemic microenvironment is still a critical challenge for future clinical application. With the aim of improving postimplantation cell survival and pulp tissue regeneration, stem cells from human exfoliated deciduous teeth (SHED) were preconditioned to a hypoxic condition by hypoxia-inducible factor 1α (HIF-1α) stabilization via knockdown of prolyl hydroxylase domain-containing protein 2 (PHD2) using lentiviral short hairpin RNA. HIF-1α-stabilized SHED were encapsulated in PuraMatrix hydrogel, injected into root canals of human tooth fragments, and implanted in the subcutaneous space of immunodeficient mice. After 28 d, enhanced dental pulp-like tissue formation was observed with a significantly higher level of vascularization, which could be attributed to both endothelial differentiation of SHED and recruitment of host blood vessels. Furthermore, dentin-like tissue formation in vivo and accelerated odontogenic/osteogenic differentiation both in vivo and in vitro were observed. At 7 d postimplantation, significantly less DNA damage and higher Ki67 expression were detected in the HIF-1α-stabilized SHED group compared with the control SHED. Accordingly, cell viability assay and staining for Ki67 and apoptotic cells in vitro showed that HIF-1α stabilization could decrease cell apoptosis and enhance cell survival significantly. We demonstrated that PI3K/AKT pathway activation had resulted in low caspase 3 expression in HIF-1α-stabilized SHED in hypoxic conditions. Furthermore, we found that HIF-1α-induced cell survival could also be attributed to the upregulated expression of PDK1, HK2, and Glut1, which contributes to the maintenance of reactive oxygen species homeostasis and metabolic adaptation in hypoxia. In addition, we identified Smad7 as 1 of the top 3 upregulated genes through RNA sequencing in HIF-1α-stabilized SHED and demonstrated its essential role in HK2 and Glut1 upregulation. Taken together, HIF-1α stabilization enhances cell survival of SHED through modulating various target genes and potential signaling pathways, as well as odontogenic tissue formation during dental pulp regeneration, which could benefit stem cell-based therapy in general.

O-302 Lower expression of AHCY is associated with increased miscarriage risk

Study question

Are alterations in the transcript levels of genes from the methionine cycle associated with maternal associated miscarriage risk?

Summary answer

Lower expression of AHCY is associated with a greater number of prior pregnancy losses

What is known already

Around 15% of pregnancies end in miscarriage, and the risk of recurrence increases with each pregnancy loss. Aberrant differentiation (decidualization) of endometrial stromal cells into specialised decidual cells to accommodate implantation is a key maternal factor for miscarriage risk.

Our previous work identified secretory changes in cysteine and methionine metabolites upon decidualization. The methionine cycle contributes to vital cellular functions, including producing methionine for proliferation, regulating cell differentiation, and S-adenosylmethionine (SAM) production. SAM is required for protein, RNA and DNA methylation, thereby influencing pathways at the metabolic, epigenetic, and proteomic levels. AHCY clears S-adenosylhomocysteine (SAH), reducing its inhibition of methylation.

Study design, size, duration

Endometrial biopsies (n = 250) were collected during the luteal phase (LH + 6-11). Patients were grouped based on their miscarriage history. Accordingly, expression of genes from the methionine cycle were quantified using RT-qPCR.

Participants/materials, setting, methods

Endometrial biopsies were obtained, with written informed consent, from women attending the Implantation Clinic at University Hospitals Coventry and Warwickshire NHS Trust, following transvaginal ultrasounds to exclude uterine pathology. Isolated RNA was converted into cDNA. Expression of AHCY, AMD1, BHMT2, CBS, MAT2A, MAT2B, and MTR were normalised to L19. Statistical analysis was performed in Graphpad Prism; with significance accepted at p &lt; 0.05. AHCY was silenced in an endometrial cell line to determine its effect on decidualization.

Main results and the role of chance

This study reports a distinct reduction in expression of methionine cycle genes (MAT2A, AHCY, AMD1, MTR, BHMT2) in the late-luteal phase of the cycle consistent with a reduction in proliferation.

By plotting percentile graphs based on the statistical distribution in gene expression for each day of the luteal phase, comparisons have been made between groups.

AHCY expression is significantly reduced in patients with increasing number of prior miscarriages, particularly between 0-2 and 5+ previous miscarriages (p = 0.0334). Neither patient age nor BMI are a factor in this reduced expression.

In contrast, there is a stromal specific increase in AHCY upon decidualization in vitro, suggesting it is required in the decidua. Silencing AHCY in an endometrial cell line significantly reduces PRL expression upon decidualization. Reduction in AHCY may lead to a decreased “methylation potential” as SAH cannot be cleared. SAH accumulation inhibits methylation, and limits SAM production, thus compounding its effect.

Decreased methylation potential could prevent differentiation of the stromal compartment, resulting in lower levels of PRL, and altering decidual timing. Therefore, an embryo may implant into a tissue primed for disintegration, resulting a miscarriage.

In summary, AHCY may contribute to aberrant decidualization augmenting the risk of miscarriage.

Limitations, reasons for caution

Results are based on endometrial biopsies from an implantation clinic, therefore studies into biopsies from women with normal reproductive histories should also be analysed. Further functional studies are needed to ascertain the mechanism of action of AHCY in miscarriage.

Wider implications of the findings

This study identified that a decrease in AHCY in whole endometrial tissue is associated with increased risk of miscarriage. Further, silencing AHCY perturbed decidual marker expression. Thus, AHCY may act as a biomarker for atypical decidualization, and the clearance of SAH may be a potential treatment.

Trial registration number

N/A