Cryo-electron microscopy for GPCR research and drug discovery in endocrinology and metabolism

G protein-coupled receptors (GPCRs) are the largest family of cell surface receptors, with many GPCRs having crucial roles in endocrinology and metabolism. Cryogenic electron microscopy (cryo-EM) has revolutionized the field of structural biology, particularly regarding GPCRs, over the past decade. Since the first pair of GPCR structures resolved by cryo-EM were published in 2017, the number of GPCR structures resolved by cryo-EM has surpassed the number resolved by X-ray crystallography by 30%, reaching >650, and the number has doubled every ~0.63 years for the past 6 years. At this pace, it is predicted that the structure of 90% of all human GPCRs will be completed within the next 5-7 years. This Review highlights the general structural features and principles that guide GPCR ligand recognition, receptor activation, G protein coupling, arrestin recruitment and regulation by GPCR kinases. The Review also highlights the diversity of GPCR allosteric binding sites and how allosteric ligands could dictate biased signalling that is selective for a G protein pathway or an arrestin pathway. Finally, the authors use the examples of glycoprotein hormone receptors and glucagon-like peptide 1 receptor to illustrate the effect of cryo-EM on understanding GPCR biology in endocrinology and metabolism, as well as on GPCR-related endocrine diseases and drug discovery.

[Endoscopic response evaluation in gastrointestinal cancers after neoadjuvant chemora- diotherapy]

Neoadjuvant chemoradiotherapy has emerged as the standard treatment for locally advanced rectal cancer, esophageal cancer and gastroesophageal junction cancer which can not only improve the rate of local control but also induce pathological complete response in some patients. For patients who have achieved clinical complete response after neoadjuvant therapy, the watch & wait strategy and organ preservation could reduce unnecessary surgery and minimize the risk of postoperative complications, meanwhile greatly improve patients' quality of life without affecting the oncologic outcome. At present, a variety of methods, including white light endoscopy, endoscopic forceps biopsy, image enhanced endoscopy, endoscopic ultrasound, endoscopic ultrasound guided fine needle aspiration, endoscopic submucosal dissection, artificial intelligence assisted technology, etc., have become important assistance for the evaluation of tumor response after neoadjuvant chemoradiotherapy and have been widely used in clinical practice. This review will briefly introduce the application of the endoscopic approaches mentioned above and some novel endoscopic techniques and developing trends in response evaluation for patients with locally advanced rectal cancer, esophageal cancer and gastroesophageal junction cancer patients receiving neoadjuvant chemoradiotherapy.

Autoimmune diseases: targets, biology, and drug discovery

Autoimmune diseases (AIDs) arise from a breakdown in immunological self-tolerance, wherein the adaptive immune system mistakenly attacks healthy cells, tissues and organs. AIDs impose excessive treatment costs and currently rely on non-specific and universal immunosuppression, which only offer symptomatic relief without addressing the underlying causes. AIDs are driven by autoantigens, targeting the autoantigens holds great promise in transforming the treatment of these diseases. To achieve this goal, a comprehensive understanding of the pathogenic mechanisms underlying different AIDs and the identification of specific autoantigens are critical. In this review, we categorize AIDs based on their underlying causes and compile information on autoantigens implicated in each disease, providing a roadmap for the development of novel immunotherapy regimens. We will focus on type 1 diabetes (T1D), which is an autoimmune disease characterized by irreversible destruction of insulin-producing β cells in the Langerhans islets of the pancreas. We will discuss insulin as possible autoantigen of T1D and its role in T1D pathogenesis. Finally, we will review current treatments of TID and propose a potentially effective immunotherapy targeting autoantigens.

[Swyer syndrome with gonadal non-dysgerminoma malignant germ cell tumors: a report of 15 cases in a national medical center]

Objective: To evaluate the incidence, treatment, and survival outcomes of Swyer syndrome with gonadal non-dysgerminoma malignant germ cell tumor (MGCT-NDG). Methods: A retrospective study was performed on Swyer syndrome patients with MGCT-NDG between January 2011 and December 2022 in Peking Union Medical College Hospital to investigate their characteristics and outcomes. Results: A total of 15 patients (4.9%, 15/307) with Swyer syndrome were identified in 307 MGCT-NDG patients. The average age at diagnosis of MGCT-NDG and Swyer syndrome were (16.8±6.7) and (16.7±6.6) years, respectively. Six cases were preoperatively diagnosed as Swyer syndrome, of which 4 cases received bilateral gonadectomy with or without hysterectomy, while the other 2 cases underwent removal of gonadal tumor and unilateral gonadectomy with hysterectomy, respectively. Of the 9 patients postoperatively diagnosed as Swyer syndrome, unilateral gonadectomy, removal of gonadal tumor, and unilateral gonadectomy with hysterectomy were performed in 6 patients, 2 patients, and 1 patient, respectively. Mixed malignant germ cell tumor (MGCT;10 cases), yolk sac tumor (4 cases), and immature teratoma (1 case) were the pathological subtypes, in the descending order. There were International Federation of Gynecology and Obstetrics (FIGO) stage Ⅰ in 6 cases, stage Ⅱ in 3 cases, stage Ⅲ in 5 cases, and stage Ⅳ in 1 case, respectively. Eleven patients received reoperation for residual gonadectomy after a average delay of (7.9±6.2) months, including 8 MGCT-NDG patients and 1 gonadoblastoma patient, no tumor involved was seen in the remaining gonads in the other 2 cases. Ten patients experienced at least one recurrence, with a median event free survival of 9 months (5, 30 months), of which 2 patients received surgery only at the time of initial treatment. All patients with recurrence received surgery and combined with postoperative chemotherapy. After a median follow-up of 25 months (15, 42 months), 10 patients were disease-free, 3 patients died of the tumor, 1 died of side effects of leukemia chemotherapy, and 1 survived with disease. Conclusion: The incidence rate of Swyer syndrome in patients with MGCT-NDG is about 4.9%; timely diagnosis and bilateral gonadectomy should be emphasized to reduce the risk of reoperation and second carcinogenesis in this population.

[Identification of lymph node metastasis related genes in prostate cancer using weighted gene co-expression network analysis]

Objective: To explore the molecular markers related to lymph node metastasis of prostate cancer (PCa) based on bioinformatics technology and carry out clinical verification. Methods: The differentially expressed genes of PCa with lymph node metastasis were screened from geo data, and the hub genes of the gene co expression network were constructed. The hub genes were incorporated into the support vector machine model to evaluate its prediction efficiency. The hub genes were verified in the TCGA data set and analyzed for immune infiltration. The clinical data of 80 patients with prostate cancer in the Fourth Hospital of Hebei Medical University from January 2019 to December 2022 were collected. The logistic risk model was used to evaluate the prediction efficiency of hub gene metastasis. Results: Five hub genes (GSK3B, TP53, PSMC6, SUMO1, PIK3CA) were identified, and the support vector machine model constructed by them had good diagnostic value (the accuracy rate was 83.87%). TCGA validation results showed that only PSMC6 was significantly differentially expressed in PCa tissues with lymph node metastasis (P<0.001). The results of immune infiltration analysis showed that the expression of PSMC6 was significantly correlated with 9 kinds of immune cells (B cells, DC, IDC, etc.). Clinical information analysis showed that the expression of PSMC6 was significantly correlated with lymph node metastasis, PSA value, T stage and Gleason score (P<0.01). Univariate logistic results showed that T stage (OR=3.230, 95%CI:1.192-8.757, P=0.021), Gleason score (OR=4.627, 95%CI:2.212-9.677, P<0.001), PSMC6 (OR=25.235, 95%CI:5.326-119.560, P<0.001) could be used as predictors of lymph node metastasis. Multivariate logistic analysis showed that PSMC6 (OR=16.537, 95%CI:2.928-93.393, P=0.001) could be used as an independent risk factor for predicting lymph node metastasis. Conclusion: PSMC6 may be used as a potential molecular marker for judging lymph node metastasis in patients with PCa.

[Clinical and genotypic analysis of hereditary spherocytosis combined with cholestasis among pediatric patients]

Objective: To understand the clinical and genetic characteristics of hereditary spherocytosis (HS) combined with cholestasis among pediatric patients. Methods: 12 cases of HS children accompanied by cholestasis at Hunan Children's Hospital were selected as the research subjects between January 2013 and December 2022. Clinical data were collected. Whole-exome sequencing was performed by second-generation sequencing. Suspected pathogenic mutation sites were verified by Sanger sequencing. Results: All pediatric patients were admitted to the hospital due to their yellow skin tone. Eight cases (66.67%) had a positive family history. The clinical manifestations were jaundice, splenomegaly (12/12), abdominal pain, anemia (4/12), and hepatomegaly (5/12). All pediatric patients had decreased hemoglobin, an increased reticulocyte ratio, total bilirubin and direct bilirubin, a positive erythrocyte fragility test, and remarkable spherical erythrocytes in their peripheral blood. Seven cases had elevated aminotransferase; four cases had severely elevated aminotransferase and bilirubin; eight cases had biliary calculi; and two cases had a dilated biliary tract. Liver pathological examination showed mild damage to the liver cells (G1S1) in three pediatric cases. Five children had a total of six unreported mutations: SPTB gene c.2431_2450del, c.4974-2A > G, c.2575G > A, and exon 22-35 deletion; ANK1 gene: c.2379-2380delC; and c .6dupC. Children still had abnormal bilirubin levels following treatment. Two pediatric cases underwent splenectomy. Bilirubin and hemoglobin levels returned to normal after surgery. Conclusion: Children with HS may experience cholestasis, and those with poor treatment results may consider undergoing a splenectomy. Six new types of variants have expanded the HS gene mutation spectrum.

[The value of T2 mapping for evaluating the pathological type, grade and depth of myometrial invasion in endometrial carcinoma]

Objective: To investigate the value of T2 map and synthetic T2WI generated by T2 mapping in evaluating the histological type, pathological classification and depth of myometrial invasion of endometrial carcinoma (EC). Methods: Seventy-three patients with pathologically proven EC diagnosed at the First Affiliated Hospital of Zhengzhou University from December 2019 to December 2021 and 42 healthy volunteers were enrolled in the study. All subjects underwent conventional MRI, diffusion weighted imaging (DWI) and T2 mapping sequence for the pelvic cavity to test the T2 values and the apparent diffusion coefficient (ADC) of the focus nidus of the patients and the normal endometrium of the volunteers. The T2 and ADC values of EC vs normal endometrium, and those of different histological types and pathological grades were compared. The receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic performance of T2 and ADC values in determining the pathological type and classification of EC. In addition, two radiologists used synthetic T2WI combined with T2 map and conventional T2WI combined with DWI, respectively, to evaluate the depth of myometrial invasion, and compared the imaging results with the results of pathological diagnosis to evaluate the diagnostic efficacy of the two methods in determining the depth of myometrial invasion. Results: The T2 and ADC values of endometrial carcinoma were 85.0 (80.8, 92.5) ms and 0.71 (0.64, 0.77) ×10(-3) mm(2)/s, respectively, which were significantly lower than those of normal endometrium [147.4 (123.4, 176.7) ms and 1.46 (1.26, 1.76)×10(-3) mm(2)/s, respectively; both P<0.05]. The T2 values of endometrioid carcinoma (EA) [84.1 (79.5, 88.7) ms] were significantly lower than those of non-EA [98.8 (92.1, 102.8) ms; P<0.05]. There was no significant difference in ADC values between EA and non-EA (P=0.075). The T2 values of G1, G2 and G3 groups in EA were 89.1 (84.4, 94.4) ms, 83.6 (80.9, 86.2) ms, and 76.5 (71.4, 80.3) ms, respectively. There were significant differences in the T2 values between G1 vs G2, G1 vs G3, and G2 vs G3 groups, respectively (all P<0.017). Significant difference was also found in the ADC values between the G1 and G3 groups (P<0.017). The area under the ROC curve (AUC) of T2 values in distinguishing EA from non-EA was 0.867. The AUC of T2 values, ADC values and their combination in predicting high-grade EA was 0.888, 0.730 and 0.895, respectively. The accuracy of synthetic T2WI+ T2 map and conventional T2WI+ DWI in the diagnosis of deep myometrial invasion was 78.1% and 79.5%, respectively, with no significant difference (P>0.05). Conclusions: T2 mapping has great potential in preoperative evaluation of EC. The quantitative T2 value can be used in the diagnosis, pathological classification and grading of EC. The combination of synthetic T2WI and T2 map may be helpful to determine the depth of myometrial invasion.

[Influencing factors of small intestinal ischemia in elderly patients with incarcerated hernia]

Objective: To investigate the factors influencing small intestinal ischemia in elderly patients with incarcerated hernia. Methods: The clinical data of 105 elderly patients admitted for surgical procedures of incarcerated hernia at Department of General Surgery, Huadong Hospital between January 2014 and December 2021 were retrospectively analyzed. There were 60 males and 45 females, aged (86.1±4.3) years (range: 80 to 96 years). They were divided into normal group (n=55) and ischemic group (n=50) according to intraoperative intestinal canal condition. The t test, χ² test and Fisher's exact probability method were used for the univariate analysis of the factors that influence intestinal ischemia in patients, and Logistic regression was used for multifactorial analysis. Results: In all patients, 18 patients (17.1%) had irreversible intestinal ischemia with bowel resection. Six patients died within 30 days, 3 cases from severe abdominal infection, 2 cases from postoperative exacerbation of underlying cardiac disease, and 1 case from respiratory failure due to severe pulmonary infection. The results of the univariate analysis showed that there were differences in gender, history of intussusception, duration of previous hernia, white blood cell count, neutrophil percentage, C-reactive protein, type of incarcerated hernia, and preoperative intestinal obstruction between the two groups (all P<0.05). The Logistic regression results showed that the short time to the previous hernia (OR=0.892, 95%CI 0.872 to 0.962, P=0.003), high C-reactive protein (OR=1.022, 95%CI 1.007 to 1.037, P=0.003), non-indirect incarcerated hernia (OR=10.571, 95%CI 3.711 to 30.114, P<0.01) and preoperative intestinal obstruction (OR=6.438, 95%CI 1.762 to 23.522, P=0.005) were independent risk factors for the development of intestinal ischemia in elderly patients with incarcerated hernia. Conclusions: The short duration of the previous hernia, the high values of C-reactive proteins, the non-indirect incarcerated hernia, and the preoperative bowel obstruction are influencing factors for bowel ischemia in elderly patients with incarcerated hernia. A timely operation is necessary to reduce the incidence of intestinal necrosis and improve the prognosis.

Isolation, identification, and evaluation of the biocontrol potential of a Bacillus velezensis strain against tobacco root rot caused by Fusarium oxysporum

AIMS

Tobacco (Nicotiana tabacum) is an economically important crop. Root rot caused by Fusarium oxysporum has become a damaging disease in N. tabacum crops grown in Henan province of China. Therefore, the objectives of this study were to screen bacterial isolates against F. oxysporum from rhizosphere soils of tobacco growing areas and to evaluate their antifungal activities, biocontrol effects, and effects on plant growth.

METHODS AND RESULTS

Nineteen strains with antifungal inhibition effects of >60% against F. oxysporum were obtained using the method of flat confrontation; the strain Ba-0321 was the strongest, with an antifungal effect of 75%. Moreover, this strain had broad spectrum antimicrobial activity to eight additional tobacco pathogens. The strain was identified as Bacillus velezensis by morphology and the 16S rDNA sequence. The B. velezensis strain Ba-0321 had strong UV resistance as well as tolerance to high temperatures and low nutrition. The bacteria inhibited spore germination and mycelial growth of F. oxysporum under in vitro co-culture conditions. In vivo assays demonstrated that the Ba-0321 strain significantly reduced the pathogenicity of F. oxysporum, resulting in a control effect on tobacco root rot of 81.00%. Simultaneously, the bacteria significantly promoted root development and the growth of tobacco plants.

CONCLUSION

Our results confirmed that the B. velezensis strain Ba-0321 has a strong antifungal effect and stress resistance that enable it to be used as a biological control agent for tobacco root rot caused by F. oxysporum.

SIGNIFICANCE AND IMPACT OF THE STUDY

Tobacco root rot caused by F. oxysporum has become a damaging disease in China. The B. velezensis strain Ba-0321 has promising application value for controlling tobacco root rot diseases, and it could provide a new biocontrol agent against root rot caused by F. oxysporum in other plant species.

[Status of fungal sepsis among preterm infants in 25 neonatal intensive care units of tertiary hospitals in China]

Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34⁺⁰ weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.

[Impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease]

Objective: This study sought to investigate the impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease. Methods: We retrospectively analyzed clinical data of male patients diagnosed with suspected coronary microvascular dysfunction (CMD) in the First Hospital of Shanxi Medical University between December 2015 and August 2021. All patients underwent the one-day rest and stress ¹³N-ammonia positron emission tomography myocardial perfusion imaging. Overall obesity was defined by body mass index (BMI) ≥28 kg/m² and abdominal obesity was defined by waist circumference ≥90 cm. Hyperemic myocardial blood flow (MBF)<2.3 ml·min^-1·g^-1 or coronary flow reserve (CFR)<2.5 were referred as CMD. All patients were grouped based on their BMI and waist circumference. MBF, CFR, the incidence of CMD, hemodynamic parameters, and cardiac function were compared among the groups. Results: A total of 136 patients were included. According to BMI and waist circumference, patients were categorized into 3 groups: control group (n=45), simple abdominal obesity group (n=53) and compound obesity group (n=38). Resting MBF did not differ between groups (F=0.02,P=0.994). Compared with the control group, hyperemic MBF was significantly lower in the simple abdominal obesity and compound obesity groups ((2.82±0.64) ml·min^-1·g^-1, (2.44±0.85) ml·min^-1·g^-1 and (2.49±0.71) ml·min^-1·g^-1, both P<0.05, respectively). Hyperemic MBF was comparable among the groups of patients with obesity (P=0.772). CFR was significantly lower in the simle abdominal obesity group compared with the control group (2.87±0.99 vs. 3.32±0.62,P=0.012). Compared with the control group, CFR tended to be lower in the compound obesity group (3.02±0.91 vs. 3.32±0.62,P=0.117). The incidence of CMD was significantly higher in both the simple abdominal obesity and compound obesity groups than in the control group (62.3%, 52.6% vs. 22.2%, both P<0.01, respectively). Waist circumference was an independent risk factor for male CMD (OR=1.057, 95%CI: 1.013-1.103, P=0.011). Conclusions: In male patients with non-obstructive coronary artery disease, abdominal obesity is associated with decreased coronary microvascular function. Male patients with simple abdominal obesity face the highest risk of CMD.

[Management and short-term outcomes of neonates born to mothers infected with SARS-CoV-2 Omicron variant]

Objective: To summarize the management and short-term outcomes of neonates delivered by mothers infected with SARS-CoV-2 Omicron variant. Methods: A retrospective study was performed on 158 neonates born to mothers infected with SARS-CoV-2 Omicron variant admitted to the isolation ward of Children's Hospital of Fudan University from March 15^th, 2022 to May 30^th, 2022. The postnatal infection control measures for these neonates, and their clinical characteristics and short-term outcomes were analyzed. They were divided into maternal symptomatic group and maternal asymptomatic group according to whether their mothers had SARS-CoV-2 symptoms. The clinical outcomes were compared between the 2 groups using Rank sum test and Chi-square test. Results: All neonates were under strict infection control measures at birth and after birth. Of the 158 neonates, 75 (47.5%) were male. The gestational age was (38⁺³±1⁺³) weeks and the birth weight was (3 201±463)g. Of the neonates included, ten were preterm (6.3%) and the minimum gestational age was 30⁺¹ weeks. Six neonates (3.8%) had respiratory difficulty and 4 of them were premature and required mechanical ventilation. All 158 neonates were tested negative for SARS-COV-2 nucleic acid by daily nasal swabs for the first 7 days. A total of 156 mothers (2 cases of twin pregnancy) infected with SARS-CoV-2 Omicron variant, the time from confirmed SARS-CoV-2 infection to delivery was 7 (3, 12) days. Among them, 88 cases (56.4%) showed clinical symptoms, but none needed intensive care treatment. The peripheral white blood cell count of the neonates in maternal symptomatic group was significantly higher than that in maternal symptomatic group (23.0 (18.7, 28.0) × 10⁹ vs. 19.6 (15.4, 36.6) × 10⁹/L, Z=2.44, P<0.05). Conclusions: Neonates of mothers infected with SARS-CoV-2 Omicron variant during third trimester have benign short-term outcomes, without intrauterine infection through vertical transmission. Strict infection control measures at birth and after birth can effectively protect these neonates from SARS-CoV-2 infection.

Characterization of biochar-derived organic matter extracted with solvents of differing polarity via ultrahigh-resolution mass spectrometry

In recent years, biochar, a porous carbon-based material, has gained attention for its application prospects in contaminated soil remediation and soil improvement. Biochar-derived organic matter has a key role in influencing the migration and transformation of soil elements and pollutants. However, existing research concerning the molecular characteristics of biochar-derived organic matter is limited. Here, we used four polar solvents - dichloromethane (CH₂Cl₂), acetone (CH₃COCH₃), methanol (CH₃OH), and distilled water (H₂O) - to extract organic matter from soybean straw biochar and wheat straw biochar by accelerated solvent extraction (ASE). We characterized the extracts using Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). We found considerable differences in organic matter according to the extraction solvents; such differences were related to the polarity of the solvent, as well as intermolecular forces between the solvent and organic matter. CH₃OH extracted the most biochar-extractable organic matter components because CH₃OH can weaken or destroy oxygen bridge bonds in biochar and form hydrogen bonds with small-molecule organic compounds. CH₃OH and H₂O have strong extraction capacity for compounds containing heteroatoms. CH₂Cl₂-extractable organic matter is relatively labile and bioavailable, while CH₃OH- and H₂O-extractable organic matters are relatively stable. In addition, the binding capacity of biochar-derived organic matter for minerals and pollutants differed among fractions, in part because of differences in molecular weight, atomic O/C and H/C ratios, heteroatom distribution, and biomolecular compounds present in biochar-derived organic matter. The findings in this study help to select appropriate extractants to analyze biochar-derived organic matter for various research purposes, and provides a theoretical basis for biochar-based remediation of contaminated soil.

A high-power long lifetime beam dump for the Thomson scattering diagnostic system in the XuanLong-50 experiment

The Energy iNNovation's XuanLong-50 is a spherical torus experiment with up to 10 s plasma operation duration. A 3 J/50 Hz pulsed laser is used in the Thomson scattering diagnostic system that is developed to measure the time evolutions of plasma electron temperature and density profiles. The expected laser pulse number is about 7.5 × 10⁶/year with a power load of 150 W. To meet at least 1-year lifetime requirement, a Chevron type beam dump with polished molybdenum plates is designed and fabricated, which absorbs the laser beam energy in a 3D structure to reduce the laser fluence deposited on the material surface. To prevent the backscattered stray light from interfering with the Thomson scattering measurements, a 7.5 m beam path with folding mirrors is set between the beam dump and the plasma scattering volumes. Details of the beam dump design procedure including the laser beam profile control, multi-pulse laser damage threshold, heat dissipation, Zemax modeling, folding mirror selection, and beam path enclosure are presented together with the testing results.

[Association between high-density lipoprotein cholesterol level and cardiovascular disease and all-cause mortality in the elderly population]

Objective: To investigate the relationship between high density lipoprotein cholesterol (HDL-C) and cardiovascular disease (CVD) and all-cause mortality in the elderly population. Methods: A total of 14 355 elderly persons aged ≥65 years, who participated in the annual physical examination in Kailuan Group in 2006 were included in this prospective cohort study. According to HDL-C level, the participants were divided into 4 groups: low-level group (HDL-C<1.30 mmol/L), intermediate-level group (1.30 mmol/L ≤HDL-C≤1.54 mmol/L), medium-high-level group (1.55 mmol/L ≤HDL-C≤1.80 mmol/L), high-level group (HDL-C≥1.81 mmol/L). Baseline data such as age, sex and blood lipid levels were collected and compared. Inpatient medical records and death information were obtained through the social security system, and CVD and all-cause mortality were analyzed. After adjusting for confounding factors, the medium-high-level group was used as the reference group. Cox proportional risk regression model was used to evaluate the impact of HDL-C on CVD and all-cause mortality events. The linear or nonlinear relationship between HDL-C level and CVD and all-cause mortality events was evaluated by restricted cubic spline regression model. Death competitive risk analysis was conducted, and sensitivity analysis was performed after excluding subjects with CVD or all-cause mortality within 1 year of follow-up and female participants. Results: The average age of this cohort was (71.5±5.5) years and follow-up time was (10.9±3.3) years. Compared with medium-high-level group, Cox proportional risk regression analysis showed that the HR (95%CI) of CVD and all-cause mortality in low-level group were 1.21 (1.06-1.38) (P<0.05) and 1.02 (0.95-1.11) (P>0.05), respectively; the HR (95%CI) of CVD events in high-level group was 1.17 (1.03-1.33) (P<0.05), and there was a marginal significant association with all-cause mortality, the HR (95%CI) was 1.07 (1.00-1.16) (0.05<P<0.1). The restricted cubic spline regression analysis showed that HDL-C was nonlinearly correlated with CVD (nonlinear correlation P<0.1), and presented a U-shaped curve trend, while HDL-C was linearly correlated with all-cause mortality (nonlinear correlation P>0.1). Conclusions: In the elderly population, the risk of CVD is lowest when the HDL-C level is 1.55-1.80 mmol/L, either high or low HDL-C is a risk factor for CVD. High HDL-C tends to be related to increased risk of all-cause mortality and low HDL-C is not related to increased risk of all-cause mortality.

A novel polychromator calibration method for Thomson scattering diagnostics

Polychromators are most frequently used in Thomson scattering (TS) diagnostics to analyze the scattered light spectrum and intensity so that the plasma electron temperature (T_e) and density (n_e) can be derived. For T_e measurements, the spectral response of the polychromator channels and the relative spectral responsivities need to be calibrated. The spectral response is calibrated with a bromine tungsten lamp and a monochromator in a conventional way. A novel method for calibrating the relative spectral responsivities of the polychromators is described in detail. A broadband pulsed Light Emission Diode (LED) is used, which has a spectral irradiance similar to that of the TS spectrum, and the LED can be driven in pulse mode with the pulse width similar to the TS signal pulse width of about 10-20 ns full width at half maximum. This new method allows for the calibration to be done after the polychromator is fully installed, and in situ system calibration can be easily performed, showing the advantages of accuracy, simplicity, efficiency, and flexibility. For n_e measurements, absolute sensitivity calibration is done by Rayleigh scattering with argon gas. Formulas for calculating the plasma density from the calibration data and the polychromator signals from the off-laser wavelength channels are presented.

Thomson scattering diagnostic system for the XuanLong-50 experiment

A 15-point Thomson scattering diagnostic system is developed for ENN's spherical torus experiment XuanLong-50 (EXL-50). A BeamTech laser with 3 J/pulse (1064 nm wavelength) at 50 Hz repetition rate is chosen for measurements during EXL-50 plasma operations. To enable measurements at low density (∼0.5 × 10¹⁸ m^-3) plasma operations, the opto-mechanical subsystems are carefully designed to maximize the collection and transmission of the scattered light and to minimize the stray light level. In addition, the high bandwidth trans-impedance amplifiers and segmented high speed waveform digitizers allow for the application of muti-pulse averaging to further improve the signal-to-noise ratio. Details of the diagnostic system are described and initial experimental results are presented.

Nicotinamide mononucleotide alleviates heat stress-induced oxidative stress and apoptosis in BMECs through reducing mitochondrial damage and endoplasmic reticulum stress

Heat stress is directly correlated to mammary gland dysfunction in dairy cows, especially in summer. Abnormally high environmental temperature induces oxidative stress and apoptosis in bovine mammary epithelial cells (BMECs). Nicotinamide mononucleotide (NMN) has beneficial effects in maintaining the cellular physiological functions. In this study, we evaluate the protective effect of NMN on heat stress-induced apoptosis of BMECs and explore the potential underlying mechanisms. Our results showed that heat stress considerably decreased cell viability in BMECs, whereas pretreatment of BMECs with NMN (150 μM) for 24 h significantly alleviated the negative effects of heat stress on cells. NMN protected BMECs from heat stress-induced oxidative stress by inhibiting the excessive accumulation of reactive oxygen species (ROS) and increasing the activity of antioxidant enzymes. It also inhibited apoptosis by reducing the ratio of Bax/Bcl2 and blocking proteolytic the cleavage of Caspase-3 in heat stressed-BMECs. Importantly, NMN treatment could reduce mitochondrial damage through mediating the expression of mitochondrial fission and fusion-related genes, including Dynamin related protein 1 (Drp1), Mitochondrial fission 1 protein (Fis1), and Mitofusin1, 2 (MFN1, 2); and suppress endoplasmic reticulum stress through unfolded protein response regulator Glucose regulated protein 78 (GRP78), and downstream elements Recombinant activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP). Above all, our results demonstrate that NMN supplemention attenuates heat stress-induced oxidative stress and apoptosis in BMECs by maintaining mitochondrial fission and fusion, and regulating endoplasmic reticulum stress, which provides the convincing evidence that NMN has valuable potential in alleviating mammary gland injury of dairy cows caused by environmental heat stress.

[Clinical application effects of two longitudes three transverses method in perforator location of thoracodorsal artery perforator flap and deep wound repair]

Objective: To explore the clinical application value of two longitudes three transverses method in the location of the perforator of thoracodorsal artery perforator and deep wound repair. Methods: The retrospectively observational study was conducted. From December 2018 to June 2020, 17 patients with deep wounds who were admitted to the Affiliated Hospital of Zunyi Medical University met the inclusion criteria and were included in this study, including 7 males and 10 females, aged 12 to 72 years. The wound areas of patients after debridement were 7 cm×3 cm to 11 cm×7 cm. Two longitudinal lines were located through the midpoint of the armpit, the posterior superior iliac spine, and the protruding point of the sacroiliac joint, and three transverse lines were located 5, 10, and 15 cm below the midpoint of the armpit between the two longitudinal lines, i.e. two longitudes three transverses method, resulting in two trapezoidal areas. And then the thoracodorsal artery perforators in two trapezoidal areas were explored by the portable Doppler blood flow detector. On this account, a single or lobulated free thoracodorsal artery perforator flap or flap that carrying partial latissimus dorsi muscle, with an area of 7 cm×4 cm to 12 cm×8 cm was designed and harvested to repair the wound. The donor sites were all closed by suturing directly. The number and location of thoracodorsal artery perforators, and the distance from the position where the first perforator (the perforator closest to the axillary apex) exits the muscle to the lateral border of the latissimus dorsi in preoperative localization and intraoperative exploration, the diameter of thoracodorsal artery perforator measured during operation, and the flap types were recorded. The survivals of flaps and appearances of donor sites were followed up. Results: The number and location of thoracodorsal artery perforators located before operation in each patient were consistent with the results of intraoperative exploration. A total of 42 perforators were found in two trapezoidal areas, with 2 or 3 perforators each patient. The perforators were all located in two trapezoid areas, and a stable perforator (the first perforator) was located and detected in the first trapezoidal area. There were averagely 1.47 perforators in the second trapezoidal area. The position where the first perforator exits the muscle was 2.1-3.1 cm away from the lateral border of the latissimus dorsi. The diameters of thoracodorsal artery perforators were 0.4-0.6 mm. In this group, 12 cases were repaired with single thoracodorsal artery perforator flap, 3 cases with lobulated thoracodorsal artery perforator flap, and 2 cases with thoracodorsal artery perforator flap carrying partial latissimus dorsi muscle. The patients were followed up for 6 to 16 months. All the 17 flaps survived with good elasticity, blood circulation, and soft texture. Only linear scar was left in the donor area. Conclusions: The two longitudes three transverses method is helpful to locate the perforator of thoracodorsal artery perforator flap. The method is simple and reliable. The thoracodorsal artery perforator flap designed and harvested based on this method has good clinical effects in repairing deep wound, with minimal donor site damage.

[Study on the diagnostic value of transient elastography, APRI and FIB-4 for liver fibrosis in children with non-alcoholic fatty liver disease]

Objective: To evaluate the diagnostic value of transient elastography, aspartate aminotransferase-to-platelet ratio index (APRI), and fibrosis index based on 4 factors (FIB-4) for liver fibrosis in children with non-alcoholic fatty liver disease (NAFLD). Methods: A retrospective study was conducted on 100 cases of nonalcoholic fatty liver disease in Hunan Children's Hospital between August 2015 to October 2020 to collect liver tissue pathological and clinical data. The receiver operating characteristic curve (ROC curve) was used to analyze the diagnostic value of liver stiffness measurement (LSM), APRI and FIB-4 in the diagnosis of different stages of liver fibrosis caused by NAFLD in children. Results: The area under the ROC curve (AUC) value of LSM, APRI and FIB-4 for diagnosing liver fibrosis (S≥1) were 0.701 [95% confidence interval (CI): 0.579 ~ 0.822, P = 0.011], 0.606 (95%CI: 0.436 ~ 0.775, P = 0.182), and 0.568 (95%CI: 0.397 ~ 0.740, P = 0.387), respectively. The best cut-off values were 6.65 kPa, 21.20, and 0.18, respectively. The AUCs value of LSM, APRI, and FIB-4 for diagnosing significant liver fibrosis (S≥ 2) were 0.660 (95% CI: 0.552 ~ 0.768, P = 0.006), 0.578 (95% CI: 0.464 ~ 0.691, P = 0.182) and 0.541 (95% CI: 0.427 ~ 0.655, P = 0.482), respectively. The best cut-off values were 7.35kpa, 24.78 and 0.22, respectively. The AUCs value of LSM, APRI and FIB-4 for the diagnosis of advanced liver fibrosis (S≥ 3) were 0.639 (95% CI: 0.446 ~ 0.832, P = 0.134), 0.613 (95% CI: 0.447 ~ 0.779, P = 0.223) and 0.587 (95% CI: 0.411 ~ 0.764, P = 0.346), respectively. The best cut-off values were 8.55kpa, 26.66 and 0.27, respectively. Conclusion: The transient elastography technique has a better diagnostic value than APRI and FIB-4 for liver fibrosis in children with NAFLD.

[Prediction of perioperative hyperkalemia in dialysis patients with secondary hyperparathyroidism]

Objective: To explore the influencing factors for serum potassium >4.4 mmol/L in the morning of parathyroidectomy in hemodialysis patients with secondary hyperparathyroidism (SHPT). Methods: The clinical data of 72 patients with SHPT who received regular hemodialysis and underwent parathyroidectomy in Guangdong Provincial People's Hospital from January 2012 to December 2018 were analyzed retrospectively. There were 37 males and 35 females, aged from 25 to 69 years, and the dialysis timespan was from 0.5 to 11 years. The levels of parathyroid hormone, serum potassium and serum calcium before hemodialysis were examined one day before operation, and hemodialysis time and dewatering volume after hemodialysis without heparin were recorded, and also the level of serum potassium in the morning of parathyroidectomy was detected. The occurrences of hyperkalemia during and after operation were studied. The factors related to hyperkalemia in the morning of parathyroidectomy were evaluated by Pearson or Spearman correlation analysis, and the cut-off values of risk factors were calculated by receiver operating characteristic (ROC) curve. Results: Serum potassium >4.4 mmol/L in the morning of parathyroidectomy existed in 23 of 72 patients. Correlation analysis showed that serum potassium one day before operation ((4.93±0.56)mmol/L, r=0.656, P<0.001) and dehydration volume ((2.37±0.75)L, r=0.261, P=0.027) were positively correlated with serum potassium in the morning of parathyroidectomy((4.16±0.54)mmol/L). Serum potassium before hemodialysis one day before operation was a main predictor for serum potassium in the morning of parathyroidectomy (AUC=0.791, P<0.001). The cut-off value of serum potassium before hemodialysis one day before operation was 5.0 mmol/L. Conclusion: Serum potassium before hemodialysis one day before operation in patients with SHPT can predict serum potassium in the morning of parathyroidectomy, offering imformation for the safety of operation.

When and How Job Design Influences Work Motivation: A Self-Determination Theory Approach

Based on self-determination theory and job characteristics theory, this study aims to provide a systematic and comprehensive model simultaneously investigating the relationship between job characteristics and two forms of work motivation (i.e., controlled motivation and autonomous motivation). To examine the proposed model, we recruited employees working in multiple Chinese industries and collected 435 valid questionnaires. The results indicate that job characteristics have a significantly positive effect on basic psychological needs satisfaction, which, in turn, positively affects autonomous motivation and negatively influences controlled motivation. In addition, basic psychological needs satisfaction mediates the linkage between job characteristics and positive or negative work motivation. Moreover, when an employee had high positive affectivity, job characteristics were more likely to fuel their basic psychological needs satisfaction. In contrast, job characteristics were more likely to be the depressor of these needs satisfaction when an employee possesses high negative affectivity. Our findings revealed that the degree of three needs satisfaction at work is a convincing and identifiable psychological mechanism between job characteristics and two types of work motivation. Also, work affectivity may influence the different perceptions of job characteristics, reminding managers that personality traits are a non-negligible factor in job design. Overall, this paper extends the application of the job characteristics model by revealing when and how job characteristics influence two types of work motivation and further puts forward managerial implications.

Calculation of the Probability Distribution of CIBS Score in Different Relationships and Its Application

Objective To derive the probability distribution formula of combined identity by state （CIBS） score among individuals with different relationships based on population data of autosomal multiallelic genetic markers. Methods The probabilities of different identity by state （IBS） scores occurring at a single locus between two individuals with different relationships were derived based on the principle of ITO method. Then the distribution probability formula of CIBS score between two individuals with different relationships when a certain number of genetic markers were used for relationship identification was derived based on the multinomial distribution theory. The formula was compared with the CIBS probability distribution formula based on binomial distribution theory. Results Between individuals with a certain relationship, labelled as RS, the probabilities of IBS=2, 1 and 0 occurring at a certain autosomal genetic marker x （that is, p_2（RSx）, p_1（RSx） and p_0（RSx））, can be calculated based on the allele frequency data of that genetic marker and the probability of two individuals with the corresponding RS relationship sharing 0, 1 or 2 identity by descent （IBD） alleles （that is, φ₀, φ₁ and φ₂）. For a genotyping system with multiple independent genetic markers, the distribution of CIBS score between pairs of individuals with relationships other than parent-child can be deducted using the averages of the 3 probabilities of all genetic markers （that is, p_2（RS）, p_1（RS） and p_0（RS））, based on multinomial distribution theory. Conclusion The calculation of CIBS score distribution formula can be extended to all kinships and has great application value in case interpretation and system effectiveness evaluation. In most situations, the results based on binomial distribution formula are similar to those based on the formula derived in this study, thus, there is little difference between the two methods in actual work.

miRNA-10a-5p inhibits cell metastasis in hepatocellular carcinoma via targeting SKA1

A variety of microRNAs (miRNAs) are involved in the occurrence and development of hepatocellular carcinoma (HCC). However, the role of miR-10a-5p in the progression of HCC remains unclear. Therefore, the purpose of this study was to determine the role of miR-10a-5p in the development of HCC and the possible molecular mechanism. miR-10a-5p expression in HCC tissues and plasma from patients was detected by quantitative real-time polymerase chain reaction. Migratory changes in HCC cells were detected after the overexpression of miR-10a-5p. Epithelial-mesenchymal transition (EMT)-related proteins were detected by Western blot. Finally, through luciferase assay and rescue experiments, the mechanism by which miR-10a-5p regulates its downstream gene, human spindle and kinetochore-associated complex subunit 1, SKA1 and the interaction between these molecules in the development of HCC were determined. The expression of miR-10a-5p was markedly downregulated in HCC tissues, cell lines, and plasma. The overexpression of miR-10a-5p significantly inhibited the migration, invasion, and EMT of HCC cells. Furthermore, SKA1 was shown to be a downstream gene of miR-10a-5p. SKA1 silencing had the same effect as miR-10a-5p overexpression in HCC. In particular, the overexpression of SKA1 reversed the inhibitory effects of miR-10a-5p in HCC. Taken together, low miR-10a-5p expression is associated with HCC progression. miR-10a-5p inhibits the malignant development of HCC by negatively regulating SKA1.

Intrinsic Spin Susceptibility and Pseudogaplike Behavior in Infinite-Layer LaNiO_{2}

The recent discovery of superconductivity in doped infinite-layer nickelates has stimulated intensive interest, especially for similarities and differences compared to that in cuprate superconductors. In contrast to cuprates, although earlier magnetization measurement reveals a Curie-Weiss-like behavior in undoped infinite-layer nickelates, there is no magnetic ordering observed by elastic neutron scattering down to liquid helium temperature. Until now, the nature of the magnetic ground state in undoped infinite-layer nickelates was still elusive. Here, we perform a nuclear magnetic resonance (NMR) experiment through ^{139}La nuclei to study the intrinsic spin susceptibility of infinite-layer LaNiO_{2}. First, the signature for magnetic ordering or freezing is absent in the ^{139}La NMR spectrum down to 0.24 K, which unambiguously confirms a paramagnetic ground state in LaNiO_{2}. Second, a pseudogaplike behavior instead of Curie-Weiss-like behavior is observed in both the temperature-dependent Knight shift and nuclear spin-lattice relaxation rate (1/T_{1}), which is widely observed in both underdoped cuprates and iron-based superconductors. Furthermore, the scaling behavior between the Knight shift and 1/T_{1}T has also been discussed. Finally, the present results imply a considerable exchange interaction in infinite-layer nickelates, which sets a strong constraint for the proposed theoretical models.

[Correlation of damage-associated molecular pattern molecules with age and body mass index]

Objective: To explore the correlation of damage-associated molecular pattern molecules(DAMPs) serum S100, C-reactive protein (CRP), serum amyloid A (SAA) and uric acid (UA) with age and body mass index (BMI) to provide direction for further study of metabolic inflammation and inflammaging. Methods: The observational study method was used,and three hundred and sixty-six healthy people (131 males and 235 females) were selected from the physical examination center of the Second People's Hospital of Hunan Province from May to October 2020. They were divided into three age groups according to the age interval of 20 years, including 156 (53 males and 103 females) aged 20-40 years, 110 (36 males and 74 females) aged 41-60 years, and 100 (42 males and 58 females) aged 61-80 years. Kruskal Wallis H test was used to compare the differences of serum S100, CRP, SAA and UA levels among different age groups. According to the Health Industry Standards of the People's Republic of China-Weight Determination for Adults, the boundary is BMI =24 kg/m². The healthy people were divided into non overweight (BMI<24 kg/m²) and overweight (BMI ≥ 24 kg/m²) two groups. The 1∶1 propensity score was used to match the age and gender. There were 96 non overweight subjects [43 males, 53 females, age 52 (35, 66) years], 96 overweight subjects [44 males, 52 females, age 52 (36, 64) years]. The serum levels of S100, CRP, SAA and UA in different BMI groups were compared by Mann-Whitney U test. Results: The median serum UA concentrations in males and females were 356 and 277 μmol/L, and the levels of serum UA of male was significantly higher than that of female (Z=-10.428, P<0.001); the median serum SAA concentrations in males and females were 3.1 mg/L and 4.4 mg/L, while the serum SAA level of female was significantly higher than that of male (Z=3.652, P<0.001); for 20-40, 41-60, and 61-80 years old group, the median concentration of serum S100 was 0.058, 0.057, 0.070 μg/L, and the median concentration of serum CRP was 0.32, 0.58, 0.93 mg/L; the median serum SAA concentrations were 3.2, 4.0, 5.2 mg/L; serum uric acid concentrations were (301.8±61.5), (298.6±69.8), (329.0±77.8) μmol/L. The levels of serum S100, CRP, SAA, UA in 61-80 years group were significantly higher than those of 20-40 years group (H=-2.749, H=-6.731, H=-5.033, H=-2.521, P=0.018, P<0.001, P<0.001, P=0.035) and 41-60 years old group (H=-2.719, H=-2.539, H=-2.540, H=-2.486, P=0.020, P=0.033, P=0.033, P=0.039).The levels of serum CRP of 41-60 years group was significantly higher than that of 20-40 years group (H=-4.108,P<0.001). There was no significant difference in levels of serum S100, SAA and UA between 20-40 years group and 41-60 years group (H=0.189, H=-2.360, H=-0.165, P=1.000, P=0.055, P=1.000); the levels of serum CRP and SAA were positively correlated with age (r_s =0.342, r_s =0.301, P<0.001, P<0.001); for overweight, non-overweight group, the median concentrations of serum S100 were 0.065 μg/L, 0.059 μg/L, the median concentrations of serum CRP were 0.92 mg/L, 0.47 mg/L, the median concentrations of serum SAA were 5.0 mg/L, 4.1 mg/L, the median concentrations of serum UA were 339.5 μmol/L, 301.5 μmol/L, the levels of CRP, SAA and UA in the overweight group were higher than those in the non-overweight group (Z=4.278, Z=2.025, Z=3.787, P<0.001, P=0.043, P<0.001); the levels of S100 in the overweight group was higher than those in the non-overweight group, but there was no significant difference in S100 between the two groups (Z=0.862, P=0.388); the levels of Serum CRP and UA were positively correlated with BMI (r_s =0.348, r_s =0.264, P<0.001, P=0.009). Conclusions: With the increase of age, the serum S100, CRP, SAA and UA levels of healthy people may be on the rise, especially the serum CRP and SAA levels are positively correlated with age; the serum S100, CRP, SAA and UA levels of overweight people may be higher than those of non-overweight people, especially the serum CRP, UA levels are positively correlated with BMI.

[Comparison of trends in congenital heart disease mortality from 1990 to 2017 between China and North America]

Objective: To compare trends in congenital heart disease (CHD) mortality between China and North America from 1990 to 2017. Methods: Using the data from the Global Burden Of Disease (GBD) study 2017, we analyzed the related indicators of CHD mortality in China and North America from 1990 to 2017, including standardized mortality, number of deaths, age distribution of death population and age-specific mortality of CHD in each birth cohort. Age-period-cohort model was used to calculate the annual percent change of age-standardized and age-specific mortality rates of CHD (% per year), period effect-adjusted age-specific mortality rates, and the relative risk of death among CHD population at different time periods (2000－2004 as reference period) and different birth cohorts (1970 as reference cohort). Results: In 2017, the age-standardized mortality rates for CHD in China and North America were 2.63/100 000 and 1.13/100 000 respectively, a decrease of 50.4% and 49.4% compared to 1990. Of all deaths from CHD in China, 76.8% were found in children under 5 years, which was higher than that in North America (51.7%). For population under 40 years, the period effect-adjusted age-specific mortality was higher in China (0.46-167.94 per 100 000 person-years) than in North America (0.68-22.47 per 100 000 person-years); whereas for population over 40 years, mortality was lower in China (0.13-0.34/100 000 person years) than in North America (0.43-0.72/100 000 person-years).From 1990 to 2017, CHD mortality in China decreased by 1.95% per year. The annual decrease of mortality ranged from 1.95% to 3.64% per year in population under 45 years, but the mortality showed increasing trends among those over 50 years. In 2015－2019, the relative risk of death from CHD decreased by 31% in China and 24% in North America. For 2015 birth cohort, the relative risk of death decreased by 84% in China and by 64% in North America. Conclusions: In the past 30 years, the risk of death from CHD in China has significantly decreased, and the survival gap with North America is dramatically narrowed. However, mortality is higher among younger populations in China than in North America, and the mortality in the elders shows increasing trends each year in China.

[Evidence summary for safety sleep protection strategy in infants]

Objective: To systematically review and summarize the relevant evidence of safe sleep protection strategies for infants at home and abroad, to provide a reference for clinical evidence-based decision-making and guideline formulation. Methods: "Infant Death/Sudden Unexpected Infant Death/Sudden Infant Death Syndrome" and "Sleep protecting program/Sleep safety/Sleeping environment" were used as search keywords. The literature retrieval for all the Chinese and English evidence on safe sleep protection strategies for infants published before March 2020 was conducted by using the National Guideline Clearinghouse (NGC), Registered Nurse' Association of Ontario (RNAO), National Institute for Health and Clinical Excellence (NICE), Scottish Intercollegiate Guidelines Network (SIGN), Guidelines International Network (GIN), JBI, Clinical Evidence, China Evidence-based Medicine Center, PubMed, Embase, CINAHL, Wanfang Data, CNKI and other databases. Inclusion criteria were guidelines, evidence summary and systematic reviews on infant safe sleep protection strategies for infants aged 0 to 1 years. The full text was available. Exclusion criteria include duplicates, directly translated documents as well as guide abstracts, discussion drafts, draft guides, interpretations, excerpts. The Appraisal of Guideline for research & Evaluation Instrument (AGREE Ⅱ) and A Measure Tool to Assess Systematic Reviews (AMSTAR 2) were used to compare and evaluate the selected literature, and extracted evidence from the literature that meets the quality standards. Results: A total of 12 articles were incorporated into study, including 1 Summary of evidence from UptoDate, 3 guidelines, and 8 systematic reviews. The results of the AGREE II quality evaluation showed that the overall quality of 3 guidelines was high. Among them, there was 1 with a recommendation level of "A", and 2 with a rating of "B". The AMSTAR 2 quality evaluation showed that the contents of the systematic reviews were relatively complete except for one literature. In the end, totally 39 terms of evidences were summarized, including 6 aspects of assessment, planning, implementation, health education (pregnant women, parents and other infant caregivers), evaluation, organization and policy. Conclusion: The evidence summary of infant safe sleep protection provides evidence support for formulating infant safe sleep care standards and carrying out scientific and high-quality clinical nursing practices.

[Effect and mechanism of PRDX1 in epithelial mesenchymal transformationin of gastric cancer cells]

Objective: To explore the effect and mechanism of peroxiredoxin1 (PRDX1) in epithelial mesenchymal transformation (EMT) of gastric cancer cells. Methods: The expression of PRDX1 protein was detected by immunohistochemistry (IHC) in 70 paraffin specimens of cancer and normal mucosa adjacent to gastric cancer, and the relationship between PRDX1 protein and clinicopathological characteristics was analyzed. Then PRDX1-small interfering RNA (siRNA) was synthetized and transfected into human gastric cancer cell line AGS, and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay was used to test cell proliferation. Transwell chamber assay was employed to test invasion of cells. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot were utilized to test the expressions of PRDX1, E-cadherin, N-cadherin, vimentin, and claudin-1. Results: The positive rate of PRDX1 protein expression in gastric cancer was 81.4%, higher than that in normal mucosa (27.1%, P<0.05). The expression of PRDX1 protein was related to invasive depth and lymph node metastasis of gastric cancer (P<0.05). The expressions of PRDX1 mRNA and protein in AGS cells (2.216±0.445, 1.212±0.136), were higher than those in GES-1 cells (0.342±0.041, 0.328±0.038) (P<0.05). When PRDX1-siRNA was transfected into AGS cells, the proliferation of AGS cells was significantly inhibited (all P<0.05). The invasion and migration rate of AGS cells in the transfection group [(112.00±17.98), (50.87±9.79)%] were significantly lower than those of the negative control group [(192.50±22.02), (83.03±8.67)%] and blank control group [(193.83±22.40), (82.40±7.21)%] (all P<0.05). The expressions of mRNA and protein of N-cadherin, vimentin and claudin-1 decreased, while the expression of E-cadherin increased when PRDX1-siRNA was transfected into AGS cells (P<0.05). Conclusion: PRDX1 may promote the development of gastric cancer by regulating the EMT of gastric cancer cells.

Preformed Cooper Pairs in Layered FeSe-Based Superconductors

Superconductivity arises from two distinct quantum phenomena: electron pairing and long-range phase coherence. In conventional superconductors, the two quantum phenomena generally take place simultaneously, while in the underdoped high- T_{c} cuprate superconductors, the electron pairing occurs at higher temperature than the long-range phase coherence. Recently, whether electron pairing is also prior to long-range phase coherence in single-layer FeSe film on SrTiO_{3} substrate is under debate. Here, by measuring Knight shift and nuclear spin-lattice relaxation rate, we unambiguously reveal a pseudogap behavior below T_{p}∼60  K in two kinds of layered FeSe-based superconductors with quasi2D nature. In the pseudogap regime, a weak diamagnetic signal and a remarkable Nernst effect are also observed, which indicates that the observed pseudogap behavior is related to superconducting fluctuations. These works confirm that strong phase fluctuation is an important character in the 2D iron-based superconductors as widely observed in high-T_{c} cuprate superconductors.

Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13  eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

Soft Tissue Characterization with Temporal Enhanced Ultrasound through Periodic Manipulation of Point Spread Function: A Feasibility Study

Temporal enhanced ultrasound (TeUS) is a tissue characterization approach based on analysis of a temporal series of US data. Previously we demonstrated that intrinsic or external micro-motions of scatterers in the tissue contribute towards the tissue classification properties of TeUS. This property is beneficial to detect early stage cancer, for example, where changes in nuclei configuration (scatteres) dominate tissue properties. In this study, we propose an analytical derivation and experiments to acquire TeUS through manipulation of US imaging parameters, which may be simpler to translate to clinical applications. The feasibility of the proposed method is demonstrated on tissue-mimicking phantoms. Using an autoencoder classifier, we are able to classify phantoms of varying elasticities and scattering sizes.

Temperature-Induced Lifshitz Transition and Possible Excitonic Instability in ZrSiSe

The nodal-line semimetals have attracted immense interest due to the unique electronic structures such as the linear dispersion and the vanishing density of states as the Fermi energy approaching the nodes. Here, we report temperature-dependent transport and scanning tunneling microscopy (spectroscopy) [STM(S)] measurements on nodal-line semimetal ZrSiSe. Our experimental results and theoretical analyses consistently demonstrate that the temperature induces Lifshitz transitions at 80 and 106 K in ZrSiSe, which results in the transport anomalies at the same temperatures. More strikingly, we observe a V-shaped dip structure around Fermi energy from the STS spectrum at low temperature, which can be attributed to co-effect of the spin-orbit coupling and excitonic instability. Our observations indicate the correlation interaction may play an important role in ZrSiSe, which owns the quasi-two-dimensional electronic structures.

Protective effect of sonic hedgehog signaling pathway activation on acute myocardial infarction

To study changes in the sonic hedgehog (Shh) signaling pathway in acute myocardial infarction (AMI) and the protective effect of changes in Shh signaling pathway activity on AMI, specific pathogen-free (SPF) C57BL/6 mice were treated with left anterior descending (LAD) ligation to establish an AMI model. The samples were collected on the 1st, 3rd, 14th, and 21st days after AMI induction. After the operations, the mice were administered the Shh signaling pathway receptor agonist SAG1.3 (5 mg/kg/d) and antagonist SANT-1 (3.3 mg/kg/d) by intraperitoneal injection. The myocardial ischemia model was established by oxygen glucose deprivation (OGD) in vitro. The AMI mouse model and the in vitro OGD-induced myocardial ischemia model were established. The Smo agonist SAG1.3 was used to activate the Shh signaling pathway, thereby reducing the expression of Bcl-2 and Bax. The number of apoptotic cells was reduced. Administration of the antagonist SANT-1 inhibited Shh signaling pathway activity by increasing the expression of Bcl-2 and Bax, and the number of apoptotic cells increased. In conclusion, activation of the Shh signaling pathway improved cardiac functions and myocardial remodeling and reduced the apoptosis of myocardial cells.

Research Progress on Human Age Estimation Based on DNA Methylation

Abstract

In forensic science practice, age is an important individual information, and one of the indicators to be considered first to depict features of the suspect. Recently, DNA methylation has become a research hotspot in age estimation because of its hig accuracy and stability. New progress has been made in specificity of DNA methylation sites, age estimation in multiple tissues, DNA methylation age estimation of minors, sensitivity of age estimation, forensic practical applications, etc. At the same time, several studies also established more accurate statistical modeling methods, eliminated differences between different detection platforms, found appropriate number of sites in models and analyzed the influence of environment and diseases. This review summarizes these to provide references.

[Effect of lncRNA-AC013472.3 on LPS-stimulated secretion of tumor necrosis factor-α in NR8383 rat alveolar macrophages]

Objective: To investigate the effect of long non-coding RNA-AC013472.3 on lipopolysaccharide (LPS)-stimulated secretion of tumor necrosis factor (TNF)-α in NR8383 rat alveolar macrophages. Methods: Silencing and overexpression models of lncRNA-AC013472.3 were established with NR8383 rat alveolar macrophages as the experimental subjects. The silencing models were divided into three groups: random nonsense negative small interfering RNA sequence (si-con) group (si-con group, si-con transfected NR8383 cells), LPS+si-con group (10 μg/L LPS was used to treat si-con transfected NR8383 cells for 24 h), and siRNA group (siRNA transfected NR8383 cells), and LPS+siRNA group (10 μg/L LPS was used to treat siRNA transfected NR8383 cells for 24 h). The overexpression models were divided into the empty plasmid (p-con) group (p-con transfected NR8383 cells), LPS+p-con group (10 μg/L LPS was used to treat p-con transfected NR8383 cells for 24 h), lncRNA overexpression plasmid (plncRNA) group (plncRNA transfected NR8383 cells), and the LPS+plncRNA group (10 μg/L LPS was used to treat plncRNA transfected NR8383 cells for 24 h). The mRNA levels of TNF-α in each group were examined by quantitative real-time PCR (qPCR). The protein levels of tumor necrosis factor receptor-related factor-6 (TRAF-6) and phosphorylated nuclear factor-κB (NF-κB) p65 were examined by Western blot. Results: In the silencing model, the mRNA levels of TNF-α, the protein levels of TRAF-6 and NF-κB p65 in the LPS+si-con group were significantly higher than those in the si-con group (2.040±0.195 vs 1.048±0.207, 0.473±0.022 vs 0.293±0.076 and 0.469±0.062 vs 0.252±0.038)(all P<0.05). The mRNA levels of TNF-α, the protein levels of TRAF-6 and NF-κB p65 in the LPS+siRNA group were significantly higher than those in the siRNA group (4.158±0.119 vs 1.028±0.019, 0.700±0.104 vs 0.231±0.023 and 0.771±0.095 vs 0.258±0.050)(all P<0.05). The relative expression levels of all indexes in the LPS+siRNA group were significantly higher than those in the LPS+si-con group (all P<0.05). In the overexpression model, the mRNA levels of TNF-α, the protein levels of TRAF-6 and NF-κB p65 in the LPS+p-con group were significantly higher than those in the p-con group (1.961±0.169 vs 0.999±0.143, 0.533±0.047 vs 0.247±0.020 and 0.565±0.108 vs 0.276±0.048) (all P<0.05). The mRNA levels of TNF-α, the protein levels of TRAF-6 and NF-κB p65 in the LPS+plncRNA group were significantly higher than those in the plncRNA group (1.322±0.110 vs 1.043±0.093, 0.347±0.035 vs 0.232±0.023 and 0.405±0.072 vs 0.268±0.031) (all P<0.05). The relative expression of all indexes in the LPS+plncRNA group were significantly lower than that in the LPS+p-con group (all P<0.05). Conclusion: LncRNA-AC013472.3 may inhibit the activation of NF-κB signaling pathway, thereby inhibiting the LPS-stimulated secretion of TNF-α in NR8383 rat alveolar macrophages.

[Value of absolute quantification of myocardial perfusion by PET in detecting coronary microvascular disease in patients with non-obstructive coronaries]

Objective: To compare the incidence of coronary microvascular disease (CMVD) between patients with non-obstructive and obstructive coronary arteries. Methods: We retrospectively analyzed 97 patients with angina pectoris, who underwent the absolute quantitative PET examination of myocardial perfusion and coronary anatomy examination within 90 days. All patients were divided into two groups: non-obstructive group (72 cases, no stenosis ≥50% in all three coronary arteries) and obstructive group (25 cases, at least one coronary stenosis ≥50%; and at least one coronary stenosis<50%). Quantitative parameters derived from PET including rest myocardial blood flow (RMBF), stress myocardial blood flow (SMBF), coronary flow reserve (CFR) and cardiovascular risk factors were compared between the two groups. CMVD was defined as CFR<2.90 and SMBF<2.17 ml·min(-1)·g(-1). Results: Incidence of CMVD was significant higher in the non-obstructive coronary arteries of the obstructive group than in the non-obstructive coronary arteries of non-obstructive group (47.1% (16/34) vs. 25.5% (55/216), χ(2)=6.738, P=0.009) while incidence of CMVD was similar between non-obstructive and obstructive patients ((44% (11/25) vs. 33.3% (24/72), χ(2)=0.915, P=0.339). RMBF ((0.83±0.14) ml·min(-1)·g(-1) vs. (0.82±0.17) ml·min(-1)·g(-1)), SMBF ((2.13±0.60) ml·min(-1)·g(-1) vs. (1.91±0.50) ml·min(-1)·g(-1)) and CFR (2.59±0.66 vs. 2.36±0.47) were similar between the two groups (all P>0.05). Conclusions: CMVD can occur in non-obstructive coronary arteries in both patients with non-occlusive coronary arteries and patients with obstructive coronary arteries. Prevalence of CMVD is significantly higher in patients with obstructive coronary arteries than in patients with non-obstructive coronary arteries. The CMVD severity is similar between the two groups.

[Total neoadjuvant therapy followed by watch and wait approach or organ preservation for MRI stratified low-risk rectal cancer: early result from a prospective, single arm trial]

Objective: To explore the safety and efficacy of watch and wait strategy and organ preservation surgery after total neoadjuvant treatment for MRI stratified low-risk rectal cancer. Methods: A prospective single arm phase Ⅱ trial developed at Department of Gastrointestinal Cancer, Peking University Cancer Hospital & Institute was preliminarily analyzed. Subjects were enrolled from August 2016 to January 2019. Low-risk rectal cancer with following MRI features were recruited: mid-low tumor, mrT2-3b, MRF (-), EMVI (-), CRM (-), differentiation grade 1-3. Patients received intensity-modulated radiotherapy (IMRT) 50.6 Gy/22f with concurrent capecitabine and 4 cycles of consolidation CAPEOX. Patients with cCR/near-cCR confirmed by physical examination, rectal MRI, endoscopy, and serum CEA were recommended for watch & wait approach or local excision (LE). The main study outcomes were 2-year organ preservation rate (OPR) and sphincter preservation rate (SPR). Results: Thirty-eight patients were eligible for analysis, including 24 males and 14 females with median age of 56 years; 9 cases of mrT2 (23.7%), 14 cases of mrT3a (36.8%) and 15 cases of mrT3b (39.5%); 5 cases of well differentiated adenocarcinoma (13.2%), 32 cases of moderately differentiated adenocarcinoma (84.2%) and 1 case of mucinous adenocarcinoma (2.6%). Carcinoemobryonic antigen (CEA) was elevated before treatment in 1 case. One case (2.6%) of grade 3 radiation dermatitis occurred during IMRT; 18 cases (47.4%) occurred grade 3 to 4 adverse events during consolidation chemotherapy. After total neoadjuvant treatment, the cCR and near-cCR rates were 42.1% (16/38) and 23.7% (9/38), respectively, while non-cCR rate was 34.2% (13/38). Twenty patients (20/38, 52.6%) of cCR or near-cCR underwent watch & wait approach, with a local regrowth rate of 20% (4/20). Four patients received LE, including one salvage LE. Thirteen patients (4 were ypCR) received radical resection, including 10 cases of initial low anterior resections (LAR), 1 cases of initial abdominal perineal resection (APR) and 2 cases of salvage LAR, four patients refused operation. The median follow-up time was 23.5 (8.5-38.3) months. At the last interview of follow-up, the OPR and SPR were 52.6% (20/38) and 84.2% (32/38), respectively. Only one patient developed lung metastasis and no local recurrence occurred after radical resection or LE. Conclusion: Total neoadjuvant treatment for low-risk rectal cancer achieves high cCR/near-cCR rate, with increased probability of receiving watch and wait approach and organ preservation in this subgroup.

Investigating Size-Dependent Conductive Properties on Individual Si Nanowires

Periodically ordered arrays of vertically aligned Si nanowires (Si NWs) are successfully fabricated by nanosphere lithography combined with metal-assisted chemical etching. By adjusting the etching time, both the nanowires' diameter and length can be well controlled. The conductive properties of such Si NWs and particularly their size dependence are investigated by conductive atomic force microscopy (CAFM) on individual nanowires. The results indicate that the conductance of Si NWs is greatly relevant to their diameter and length. Si NWs with smaller diameters and shorter lengths exhibit better conductive properties. Together with the I-V curve characterization, a possible mechanism is supposed with the viewpoint of size-dependent Schottky barrier height, which is further verified by the electrostatic force microscopy (EFM) measurements. This study also suggests that CAFM can act as an effective means to explore the size (or other parameters) dependence of conductive properties on individual nanostructures, which should be essential for both fabrication optimization and potential applications of nanostructures.

MicroRNA-124 regulates lactate transportation in the muscle of largemouth bass (micropterus salmoides) under hypoxia by targeting MCT1

Carbohydrate metabolism switches from aerobic to anaerobic (glycolysis) to supply energy in response to acute hypoxic stress. Acute hypoxic stress with dissolved oxygen (DO) levels of 1.2 ± 0.1 mg/L for 24 h and 12 h re-oxygenation was used to investigate the response of the anaerobic glycolytic pathway in Micropterus salmoides muscle. The results showed that the glucose concentration was significantly lower in muscle, while the lactic acid and pyruvic acid concentrations tended to increase during hypoxic stress. No significant difference was observed in muscle glycogen, and ATP content fluctuated significantly. The activities of gluconeogenesis-related enzymes were slightly elevated, such as phosphoenolpyruvate carboxykinase (PEPCK). The activities of the glycolytic enzymes increased after the induction of hypoxia, such as hexokinase (HK), pyruvate kinase (PK), and lactate dehydrogenase (LDH). Curiously, phosphofructokinase (PFK) activity was significantly down-regulated within 4 h during hypoxia, although these effects were transient, and most indices returned to control levels after 12 h of re-oxygenation. Upregulated hif-1α, ampkα, hk, glut1, and ldh mRNA expression suggested that carbohydrate metabolism was reprogrammed under hypoxia. Lactate transport was regulated by miR-124-5p according to quantitative polymerase chain reaction and dual luciferase reporter assays. Our findings provide new insight into the molecular regulatory mechanism of hypoxia in Micropterus salmoides muscle.

Research Progress on Forensic Genetics of Facial Morphological Depiction

Abstract

Forensic DNA phenotyping （FDP） analysis uses DNA from biological samples left in crime scenes to predict individual phenotypic traits, such as geographical origin of ethnic group, height, weight, skin color, hair color and shape, iris color, male baldness, facial morphology, age, etc., thereby providing clues for case investigations. Among these traits, features of facial morphology are relatively more complicated. This paper makes an overall analysis of the measurement and collection of facial morphology, research on facial morphology related genes, forensic application and establishment of facial morphology depiction model, ethical issues, etc., then summarizes the latest research progress on features of facial morphology.