A potential virulence factor: Brucella flagellin FliK does not affect the main biological properties but inhibits the inflammatory response in RAW264.7 cells

The bacterial flagellum is an elongated filament that protrudes from the cell and is responsible for bacterial motility. It can also be a pathogen-associated molecular pattern (PAMP) that regulates the host immune response and is involved in bacterial pathogenicity. In contrast to motile bacteria, the Brucella flagellum does not serve a motile purpose. Instead, it plays a role in regulating Brucella virulence and the host's immune response, similar to other non-motile bacteria. The flagellin protein, FliK, plays a key role in assembly of the flagellum and also as a potential virulence factor involved in the regulation of bacterial virulence and pathogenicity. In this study, we generated a Brucella suis S2 flik gene deletion strain and its complemented strain and found that deletion of the flik gene has no significant effect on the main biological properties of Brucella, but significantly enhanced the inflammatory response induced by Brucella infection of RAW264.7 macrophages. Further experiments demonstrated that the FliK protein was able to inhibit LPS-induced cellular inflammatory responses by down-regulating the expression of MyD88 and NF-κB, and by decreasing p65 phosphorylation in the NF-κB pathway; it also inhibited the expression of NLRP3 and caspase-1 in the NLRP3 inflammasome pathway. In conclusion, our study suggests that Brucella FliK may act as a virulence factor involved in the regulation of Brucella pathogenicity and modulation of the host immune response.

Mouse model of Graves' orbitopathy induced by the immunization with TSHR A and IGF-1R α subunit gene

PURPOSE

The study aimed to establish a mouse model of Graves' disease (GD) with Graves' orbitopathy (GO; GD + GO) that can represent the clinical disease characteristics.

METHODS

A eukaryotic expression plasmid of insulin-like growth factor 1 receptor (IGF-1R) α subunit (pcDNA3.1/IGF-1Rα) and a thyrotropin receptor (TSHR) A subunit plasmid (pcDNA3.1/TSHR-289) were injected in female BALB/c mice followed by immediate electroporation to induce a GD + GO model. Grouping was performed according to the frequency of injection (2- to 4-week intervals) and type of injected plasmids: T: pcDNA3.1/TSHR-289( +), I: pcDNA3.1/IGF-1Rα( +), or co-injection T + I: pcDNA3.1/TSHR-289( +) and pcDNA3.1/IGF-1Rα( +). Serum TSH, T4, TSAb, TSBAb, body weight, and blood glucose levels were evaluated. Thyroid 99mTcO4- imaging and retrobulbar magnetic resonance imaging (MRI) were performed, and bilateral eye muscle volumes were measured. Immunohistochemistry and hematoxylin-eosin staining were performed on the relevant tissues, and semi-quantitative analysis was performed.

RESULTS

A total of 60% of mice (3/5, one mouse died) in the T group developed GD + GO. In the T + I group, 83.3% of mice (5/6) developed GD + GO. Mice in the I group did not develop GD. Compared with the control group, serum T4, TSAb, and TSBAb of the mice in the GD + GO model groups were increased to varying degrees (P < 0.05), and serum TSH and body weight were significantly lower compared to the control group (P < 0.05). The thyroid uptake capacity of 99mTcO4- and the volume of eye muscle of mice in the GD + GO group were significantly higher compared to the control group (P < 0.05). The thyroid and retrobulbar muscles of these mice showed varying inflammatory infiltration and interstitial muscle edema. The severity of GD + GO in the co-injection group was not related to injection frequency; however, GD and ocular signs in co-injection mice were more severe compared to the T group.

CONCLUSIONS

We successfully induced a GD + GO mouse model by a repeated co-injection of pcDNA3.1/IGF-1Rα and pcDNA3.1/TSHR-289 plasmids. Injection of pcDNA3.1/IGF-1Rα alone failed to induce GD. Co-injection of two plasmids induced more severe GD + GO than pcDNA3.1/TSHR-289( +) alone.

Fruit but not vegetable consumption is beneficial for low prevalence of colorectal polyps in a high-risk population: findings from a Chinese Lanxi Pre-colorectal Cancer Cohort study

PURPOSE

The available evidence regarding the role of fruit and vegetable consumption in the development of colorectal polyps remains inconclusive, and there is a lack of data on different histopathologic features of polyps. We aimed to evaluate the associations of fruit and vegetable consumption with the prevalence of colorectal polyps and its subtypes in a high-risk population in China.

METHODS

We included 6783 Chinese participants aged 40-80 years who were at high risk of colorectal cancer (CRC) in the Lanxi Pre-colorectal Cancer Cohort (LP3C). Dietary information was obtained through a validated food-frequency questionnaire (FFQ), and colonoscopy screening was used to detect colorectal polyps. Dose-response associations of fruit and vegetable intake with the prevalence of polyps were calculated using multivariate-adjusted regression models, which was reported as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

2064 cases of colorectal polyps were ascertained in the LP3C during 2018-2019. Upon multivariable adjustments, including the diet quality, fruit consumption was inversely associated with the prevalence of polyps (P trend = 0.02). Participants in the highest tertile of fruit intake had a 25% lower risk (OR: 0.75; 95% CI 0.62‒0.92) compared to non-consumers, while vegetable consumption had no significant association with polyp prevalence (P trend = 0.86). In terms of colorectal histopathology and multiplicity, higher fruit intake was correlated with 24, 23, and 33% lower prevalence of small polyps (OR: 0.76; 95% CI 0.62‒0.94; P trend = 0.05), single polyp (OR: 0.77; 95% CI 0.62‒0.96; P trend = 0.04), and distal colon polyps (OR: 0.67; 95% CI 0.51‒0.87; P trend = 0.003), respectively.

CONCLUSIONS

Fresh fruit is suggested as a protective factor to prevent colorectal polyps in individuals at high risk of CRC, and should be underscored in dietary recommendations, particularly for high-risk populations.

Dissolution of mixed oxide(MOX) fuel in nitric acid:A review

The fast neutron reactor is an internationally promising fourth-generation reactor. The main fuel for this reactor is a mixed oxide fuel, and its reprocessing is currently one of the technical challenges being tackled by various countries. One of the difficulties in the reprocessing of mixed oxide (MOX) fuel lies in the nitric acid dissolution process. The high Pu content in MOX fuel can lead to issues such as solvent radiolysis, nuclear criticality, increased insoluble residues, and slow dissolution rates during the nitric acid dissolution process. These challenges have yet to be effectively addressed. This article discusses the chemical aspects of nitric acid dissolution of MOX fuel and investigates the impact of fuel manufacturing processes, the addition of metal catalyst ions, hydrofluoric acid addition, fuel plutonium content, dissolution temperature, and ultrasonic assistance on the nitric acid dissolution of MOX fuel. A review of various countries' engineering practices related to MOX fuel dissolution is presented. Based on the research findings and experiences, a potentially feasible future industrial processing route for MOX fuel is proposed, and future research priorities are outlined.

[Application value of laparoscopic double stapler firings and double stapling technique combined with rectal eversion and total extra-abdominal resection in the sphincter-preserving resection of low rectal cancer]

Objectives: To investigate the application value of laparoscopic double stapler firings and double stapling technique combined with rectal eversion and total extra-abdominal resection (LDER) in the anal preservation treatment of low rectal cancer. Methods: Inclusion criteria: (1) age was 18-70; (2) the distance of the lower tumor edge from the anal verge was 4-5 cm; (3) primary tumor with a diameter ≤3 cm; (4) preoperative staging of T1~2N1~2M0; (5) "difficult pelvis", defined as ischial tuberosity diameter<10 cm or body mass index>25 kg/m2; (6) patients with strong intention for sphincter preservation; (7) no preoperative treatment (e.g., chemotherapy, radiotherapy, molecular targeted therapy, or immunotherapy); (8) no lateral lymph node enlargement; (9) no previous anorectal surgery; (10) patients with good basic condition who could tolerate surgery. Exclusion criteria: (1) previously suffered from malignant tumors of the digestive tract or currently suffering from malignant tumors out of the digestive tract; (2) patients with preoperative anal dysfunction (Wexner score ≥ 10), or fecal incontinence. The specific surgical steps are as follows: the distal end of the rectum was dissected to the level of the interspace between internal and external sphincters of anal canal. Five centimeters proximal to the tumor, the mesorectum was ligated, and a liner stapler was used to transect the rectum. The distal rectum with the tumor were then everted and extracted through the anus. The rectum was transected 0.5-1.0 cm distal to the tumor with a linear stapler. Full thickness suture was used to reinforce the stump of the rectum, which was then brought back into the pelvic cavity. Finally, an end-to-end anastomosis between the colon and the rectum was performed. A retrospective descriptive study was performed of the clinical and pathological data of 12 patients with T1-T2 stage low rectal cancer treated with LDER at Henan Provincial People's Hospital from January 2020 to December 2022. Results: All 12 patients successfully completed LDER with sphincter preservation, without conversion to open surgery or changes in surgical approach. The median surgical time was 272 (155-320) minutes, with a median bleeding volume of 100 (50-200) mL. No protective stoma was performed, and all patients received R0 resection. The average hospital stay was 9 (7-15) days. There were no postoperative anastomotic leakage or perioperative deaths. All 12 patients received postoperative follow-up, with a median follow-up of 12 months (6-36 months) and a Wexner score of 8 (5-14) at 6 months postoperatively. There was no tumor recurrence or metastasis during the follow-up period. Conclusions: LDER is safe and effective for the treatment of low rectal cancer.

Identification and validation of a novel cuproptosis signature for stratifying different prognostic, immune, metabolic, and therapeutic landscapes in pancreatic adenocarcinoma

OBJECTIVE

Pancreatic adenocarcinoma (PAAD) is a highly malignant cancer that urgently needs more effective therapeutic strategies. The discovery of cuproptosis brings great inspiration for the treatment and clinical assessment of cancers.

MATERIALS AND METHODS

A novel cuproptosis-related (CR) risk signature was constructed using the Lasso regression analysis. Its prognostic value was assessed via a series of survival analyses and validated in four GEO cohorts. The effects of CR risk signature on tumor immune microenvironment (TIM) were explored through CIBERSORT, ESTIMATE, and ssGSEA algorithms. Using GESA, we investigated its associations with various patterns of programmed cell death (PCD) and the metabolism process. The somatic mutation features of each CR-risk group were also probed using 'maftools' R package and cBioPortal database. The potential linkages between CR risk score and the efficacy of multiple therapeutic approaches were elucidated using tumor mutation burden, the expressions of immune checkpoints, the TIDE score, and the GDSC database. Finally, we ascertained the biofunctions of LIPT1 (Lipoyltransferase 1) in pancreatic cancer (PC) cells through immunohistochemistry, qPCR (quantitative polymerase chain reaction), colony formation, and Transwell assays.

RESULTS

LIPT1, LIAS (lipoyl synthase), PDP1 (Pyruvate dehydrogenase phosphatase1), and GCSH (Glycine cleavage system H protein) constituted the CR risk signature. The CR risk signature possessed a high prognostic value and could improve the traditional prognostic model. Moreover, the CR risk score was indicative of the changes in infiltration levels of CD8+T cells and macrophages, whereas it was not associated with the enrichment of various PCD patterns and multiple metabolic processes. As for therapeutic correlation, CR risk score was a potential biomarker for predicting the efficacy of ICBs but failed in targeted drugs and chemotherapeutic agents. Through qPCR and immunohistochemistry detection in clinical samples, we confirmed that LIPT1 was significantly downregulated in pancreatic adenocarcinoma (PAAD) samples. Experiments in vitro revealed that silencing LIPT1 promoted the proliferation, migration, and invasion of PANC-1 and SW1990 cells.

CONCLUSIONS

The novel CR risk signature contributed to the risk stratification of PAAD patients. Cuproptosis regulatory genes, well represented by LIPT1, provided new insights into PAAD treatment and assessment.

Defining metabolic flexibility in hair follicle stem cell induced squamous cell carcinoma

Among the numerous changes associated with the transformation to cancer, cellular metabolism is one of the first discovered and most prominent[1, 2]. However, despite the knowledge that nearly every cancer is associated with the strong upregulation of various metabolic pathways, there has yet to be much clinical progress on the treatment of cancer by targeting a single metabolic enzyme directly[3-6]. We previously showed that inhibition of glycolysis through lactate dehydrogenase (LDHA) deletion in cancer cells of origin had no effect on the initiation or progression of cutaneous squamous cell carcinoma[7], suggesting that these cancers are metabolically flexible enough to produce the necessary metabolites required for sustained growth in the absence of glycolysis. Here we focused on glutaminolysis, another metabolic pathway frequently implicated as important for tumorigenesis in correlative studies. We genetically blocked glutaminolysis through glutaminase (GLS) deletion in cancer cells of origin, and found that this had little effect on tumorigenesis, similar to what we previously showed for blocking glycolysis. Tumors with genetic deletion of glutaminolysis instead upregulated lactate consumption and utilization for the TCA cycle, providing further evidence of metabolic flexibility. We also found that the metabolic flexibility observed upon inhibition of glycolysis or glutaminolysis is due to post-transcriptional changes in the levels of plasma membrane lactate and glutamine transporters. To define the limits of metabolic flexibility in cancer initiating hair follicle stem cells, we genetically blocked both glycolysis and glutaminolysis simultaneously and found that frank carcinoma was not compatible with abrogation of both of these carbon utilization pathways. These data point towards metabolic flexibility mediated by regulation of nutrient consumption, and suggest that treatment of cancer through metabolic manipulation will require multiple interventions on distinct pathways.

m6A Reader YTHDC1 Inhibits Ferroptosis and Radiosensitivity by Promoting SREBF1 mRNA Nuclear Export in Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

Radioresistance is the main reason for nasopharyngeal carcinoma (NPC) recurrence leading to treatment failure, and inducing ferroptosis has gradually been a new way to enhance radiosensitivity. N6-methyladenosine (m6A) is involved in regulation of numerous biological processes. However, whether m6A affects ferroptosis in NPC is still unclear. In this study, we conducted a siRNA library screening to identify m6A reader YTHDC1 as an essential oncogene that suppressed ferroptosis and radiosensitivity by promoting SREBF1 mRNA nuclear export in nasopharyngeal carcinoma.

MATERIALS/METHODS

The expression and function of YTHDC1 were assessed via CCK8 cell viability assay, immunostaining, real-time PCR, western blot, radiation clonogenic assay and fluorescence in situ hybridization assay. Ferroptosis was determined by detecting cell viability, lipid peroxidation, abnormal mitochondrial and cell death rate. The in vivo effects of YTHDC1 were examined with RSL3 treatment or lentivirus modification of YTHDC1 expression in radiated mouse models.

RESULTS

Based on RSL3-induced ferroptotic cell death model and a siRNA library about m6A modification associated gene screening, we identified m6A reader YTHDC1 could inhibit ferroptosis as well as radiosensitivity of NPC, both in vivo and in vitro. Mechanistically, YTHDC1 protein could recognize m6A sites in the CDS region and 3' untranslated region (3'UTR) of SREBF1 mRNA and promote SREBF1 mRNA nuclear export, which finally resulted in transcriptional upregulation of genes key to ferroptosis such as SCD and FASN. Furthermore, the high expression of YTHDC1 was negatively regulated by ZNF598 via ubiquitination and associated with unfavorable survival in NPC patients due to radioresistance.

CONCLUSION

Our findings reveal the critical role of YTHDC1 specifically in inhibiting ferroptosis and radiosensitivity via m6A-dependent mechanism and provide an exploitable target and therapeutic strategy for overcoming radioresistance in NPC.

Influence of off-hours admission on outcomes of ischemic stroke: a systematic review and meta-analysis of contemporary studies

OBJECTIVE

The aim of this study was to document pooled evidence on the association between admission during off-hours and/or weekends and the risk of mortality and poor functional outcome in patients with ischemic stroke, as compared to admission during regular working hours and/or weekdays.

MATERIALS AND METHODS

We conducted a systematic search using PubMed, EMBASE, and Scopus databases. Observational studies published between 2013 and 2023 that investigated the association between weekend/off-hours admission and outcomes (mortality and functional outcomes) of ischemic stroke were considered for inclusion. A random effects model was used to conduct the analysis, and effect sizes were reported as pooled odds ratio (OR) or hazards ratio (HR) with corresponding 95% confidence intervals.

RESULTS

The analysis consisted of 31 studies and found that patients admitted during weekend/off-hours had a higher risk of in-hospital (OR 1.12, 95% CI: 1.06, 1.18), and 1-month post-admittance mortality (OR 1.13, 95% CI: 1.06, 1.20). However, the risk of mortality after 3, 6, and 12 months was not statistically different between the two patient groups. Patients admitted during weekends/off-hours had a slightly higher risk of poor functional outcomes (modified Rankin Scale score of ≥3) at 1-month post-admittance (OR 1.06, 95% CI: 1.00, 1.11). However, after 3, 6, and 12 months, the risk of poor functional outcomes was similar in both patient groups. Egger's test did not suggest the presence of publication bias for any of the outcomes.

CONCLUSIONS

Individuals who suffer from ischemic stroke and present outside of regular working hours or on weekends have a higher likelihood of experiencing short-term mortality and unfavorable functional outcomes.

[The effects of high risk of ovarian hyperstimulation syndrome and duration of embryo cryopreservation on perinatal outcomes of single live births in the first frozen embryo transfer cycle after whole embryo cryopreservation]

Objective: To investigate the effects of high risk of ovarian hyperstimulation syndrome (OHSS) and duration of embryo cryopreservation on perinatal outcomes of the first frozen-thawed cycle after whole embryo cryopreservation. Methods: The clinical data of 1 804 patients who underwent the first frozen-thawed cycle after whole embryo cryopreservation and achieved singleton live births in the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University from January 2016 to June 2021 were retrospectively analyzed. According to whether there was high risk of OHSS in the oocyte retrieval cycle, the patients were divided into high-risk group (n=790) and non-high-risk group (n=1 014). The baseline data and perinatal outcomes were compared between the two groups. Multivariate linear regression was applied to analyze the relative factors affecting neonatal weight. And the high-risk group was divided into three subgroups according to different cryopreservation time: the embryos of 96 cycles with a cryopreservation time less than 60 days were defined as group A; the embryos of 587 cycles with a cryopreservation time around 60 to 120 days were defined as group B; the embryos of 107 cycles with a cryopreservation time more than 120 days were defined as group C. The perinatal outcomes were compared among the three groups. The measurement data in this study were represented by［M（Q₁，Q₃）］. Results: The female age in the high-risk group was 30.0 (27.0, 32.0) years old, which was lower than that in the non-high-risk group 31.0 (29.0, 34.0) (P<0.001). The male age in high-risk group was 30.0 (28.0, 33.0), lower than that in non-high-risk group 32.0 (29.0, 35.0) (P<0.001). The birth weight of high-risk group [3 500.0 (3 200.0,3 800.0) g] was higher than that of control group [3 400.0 (3 150.0,3 800.0) g](P=0.045). Multivariate linear regression analysis showed that female BMI was correlated with neonatal weight, β (95%CI) was 15.37(8.33, 22.41) (P<0.001), and the high risk of OHSS was not correlated with neonatal weight, β (95%CI) was 19.40 (-38.07, 76.87) (P=0.508). There was significant difference in the incidence of low birth weight and very low birth weight among groups A, B and C (all P values<0.05), and the incidence of low birth weight and very low birth weight in group C was higher than that in group B (all P values<0.017). Conclusions: The risk of adverse perinatal outcomes in high-risk OHSS patients who underwent the first frozen-thawed cycle after whole embryo cryopreservation was not increased. However, prolonged cryopreservation of embryos may lead to increased risk of low birth weight and very low birth weight.

[The relationship between genetic polymorphism of CYP2C19 and the efficacy of Helicobacter pylori eradication therapy in children]

Objective: To investigate the relationship between genetic polymorphisms of cytochrome P450 2C19 (CYP2C19) and the efficacy of Helicobacter pylori (Hp) eradication therapy in children. Methods: The retrospective cohort study was conducted on 125 children with gastroscopy and positive rapid urease test (RUT) from September 2016 to December 2018 who presented to the Children's Hospital of Zhejiang University School of Medicine due to gastrointestinal symptoms including nausea, vomiting, abdominal pain, bloating, acid reflux, heartburn, chest pain, vomiting blood and melena. Hp culture and drug susceptibility test were carried out with gastric antrum mucosa before treatment. All the patients completed 2 weeks of standardized Hp eradication therapy and had ¹³C urea breath test 1 month after that, which was used to evaluate the curative effect. The DNA of gastric mucosa after RUT was analyzed and CYP2C19 gene polymorphism was detected. Children were grouped according to metabolic type. Combined with the results of Hp culture and drug susceptibility, the relationship between CYP2C19 gene polymorphism and the efficacy of Hp eradicative treatment was analyzed in children. Chi square test was used for row and column variables, and Fisher exact test was used for comparison between groups. Results: One hundred and twenty five children were enrolled in the study, of whom 76 were males and 49 females. The genetic polymorphism of CYP2C19 in these children found poor metabolizer (PM) of 30.4% (38/125), intermediate metabolizer (IM) of 20.8% (26/125), normal metabolizer (NM) of 47.2% (59/125), rapid metabolizer (RM) of 1.6% (2/125), and ultrarapid metabolizer (UM) of 0. There were statistically significant in positive rate of Hp culture among these groups (χ²=124.00, P<0.001). In addition, the successful rates of Hp eradication in PM, IM, NM and RM genotypes were 84.2% (32/38), 53.8% (14/26), 67.8% (40/59), and 0, respectively, with significant differences (χ²=11.35, P=0.010); those in IM genotype was significantly lower than that in PM genotype (P=0.011). With the same standard triple Hp eradicative regimen, the successful rate of Hp eradication for IM type was 8/19, which was lower than that of PM (80.0%, 24/30) and NM type (77.3%, 34/44) (P=0.007 and 0.007, respectively). There was a significant difference in the efficacy of Hp eradication treatment among different genotypes (χ²=9.72, P=0.008). According to the clarithromycin susceptibility result, the successful rate of Hp eradication treatment for IM genotype was 4/15 in the sensitive group and 4/4 in the drug-resistant group (χ²=6.97, P=0.018). Conclusions: The genetic polymorphism of CYP2C19 in children is closely related to the efficacy of Hp eradication treatment. PM has a higher successful rate of eradication treatment than the other genotypes.

Targeted metabolomics analysis of nucleosides and the identification of biomarkers for colorectal adenomas and colorectal cancer

The morbidity and mortality of colorectal cancer (CRC) have been increasing in recent years, and early detection of CRC can improve the survival rate of patients. RNA methylation plays crucial roles in many biological processes and has been implicated in the initiation of various diseases, including cancer. Serum contains a variety of biomolecules and is an important clinical sample for biomarker discovery. In this study, we developed a targeted metabolomics method for the quantitative analysis of nucleosides in human serum samples by using liquid chromatography with tandem mass spectrometry (LC-MS/MS). We successfully quantified the concentrations of nucleosides in serum samples from 51 healthy controls, 37 patients with colorectal adenomas, and 55 patients with CRC. The results showed that the concentrations of N ⁶-methyladenosine (m⁶A), N ¹-methyladenosine (m¹A), and 3-methyluridine (m³U) were increased in patients with CRC, whereas the concentrations of N ²-methylguanosine (m²G), 2'-O-methyluridine (U_m), and 2'-O-methylguanosine (G_m) were decreased in patients with CRC, compared with the healthy controls and patients with colorectal adenomas. Moreover, the levels of 2'-O-methyluridine and 2'-O-methylguanosine were lower in patients with colorectal adenomas than those in healthy controls. Interestingly, the levels of U_m and G_m gradually decreased in the following order: healthy controls to colorectal adenoma patients to CRC patients. These results revealed that the aberrations of these nucleosides were tightly correlated to colorectal adenomas and CRC. In addition, the present work will stimulate future investigations about the regulatory roles of these nucleosides in the initiation and development of CRC.

Associations of specific dietary unsaturated fatty acids with risk of overweight/obesity: population-based cohort study

Background

The role of specific unsaturated fatty acids (FAs) in the development of overweight/obesity remains unclear in the general population. Here, we aimed to explore the associations of different types of unsaturated FAs with overweight/obesity risk among the Chinese population.

Methods

Eight thousand seven hundred forty-two subjects free of overweight/obesity at entry in the China Health and Nutrition Survey (CHNS) were followed up until 2015. Dietary unsaturated FAs were assessed by 3-day 24-h recalls with a weighing method in each wave. Cox regression models were used to obtain the hazard ratios (HRs) and 95% confidence intervals (CIs) for overweight/obesity risk associated with unsaturated FAs.

Results

During a median follow-up of 7 years, 2,753 subjects (1,350 males and 1,403 females) developed overweight/obesity. Consuming more monounsaturated FAs (MUFAs) was associated with a lower risk of overweight/obesity (highest vs. lowest quartile: HR 0.80, 95% CI 0.67-0.96; P-trend = 0.010). Similar inverse associations were observed for plant-MUFAs (HR_Q4vsQ1 0.83, 95% CI: 0.73-0.94; P-trend = 0.003) and animal-MUFAs (HR_Q4vsQ1 0.77, 95% CI: 0.64-0.94; P-trend = 0.004), total dietary oleic acid (OA) (HR_Q4vsQ1 0.66, 95% CI: 0.55-0.79; P-trend <0.001), plant-OA (HR_Q4vsQ1 0.73, 95% CI: 0.64-0.83; P-trend <0.001) and animal-OA (HR_Q4vsQ1 0.68, 95% CI: 0.55-0.84; P-trend <0.001). In addition, the intakes of n-3 polyunsaturated FAs (PUFAs) (HR_Q4vsQ1 1.24, 95% CI: 1.09-1.42; P-trend = 0.017) and α-linolenic acid (ALA) (HR_Q4vsQ1 1.22, 95% CI: 1.07-1.39; P-trend = 0.039) but not marine n-3 PUFAs were positively linked to overweight/obesity risk. Consumption of n-6 PUFAs (HR_Q4vsQ1 1.13, 95% CI: 0.99-1.28; P-trend = 0.014) and linoleic acid (LA) (HR_Q4vsQ1 1.11, 95% CI: 0.98-1.26; P-trend = 0.020) had marginal and positive relationships with the incidence of overweight/obesity. N-6/n-3 PUFA ratio ranging from 5.7 to 12.6 was related to higher risk of overweight/obesity.

Conclusion

Higher dietary intake of MUFAs was associated with lower overweight/obesity risk, which was mainly driven by dietary OA from either plant or animal sources. Intakes of ALA, n-6 PUFAs and LA were related to higher risk of overweight/obesity. These results support consuming more MUFAs for maintaining a healthy body weight among the Chinese population.

[Enhance the management of cardiac arrest and improve the prognosis of the patients]

Cardiac arrest is one of the major public health problems with sudden onset, high mortality and high disability rate. The prevalence of cardiovascular disease continues to rise and the burden of cardiac arrest is increasing in China. It is of great significance to explore more effective prevention and treatment measures to improve the prognosis of patients with cardiac arrest. This article discusses the relevant progress on the treatment ability of emergency and critical cardiovascular diseases, medicines and technologies for cardiac arrest care, and registry studies of cardiac arrest, to further promote the effective improvement of key capacities at various stages of the prevention and treatment of cardiac arrest in China.

[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.

Association of egg consumption with colorectal polyp prevalence: findings from the Lanxi Pre-Colorectal Cancer Cohort (LP3C) in China

Eggs contain high-quality protein, lavish vitamins and other bioactive nutrients but are rich in cholesterol. Our study is designed to assess the association of egg intake with polyp prevalence. A total of 7068 participants at a high risk of CRC from the Lanxi Pre-Colorectal Cancer Cohort Study (LP3C) were recruited. A food frequency questionnaire (FFQ) was utilized to obtain dietary data through a face-to-face interview. Cases of colorectal polyps were identified by electronic colonoscopy. The logistic regression model was exploited to achieve odds ratios (ORs) and 95% confidence intervals (CIs). Overall 2064 cases of colorectal polyps were identified in the 2018-2019 survey of LP3C. A positive association of egg consumption with colorectal polyp prevalence was found after the multivariable adjustment [OR_{Q4 vs. Q1} (95% CI): 1.23 (1.05-1.44); P_trend = 0.01]. However, a positive relationship disappeared after further adjustment for dietary cholesterol (P_trend = 0.37), which explained that the harmful role of eggs could be ascribed to the high content of dietary cholesterol. Besides, a positive trend was found between dietary cholesterol and polyp prevalence [OR (95% CI): 1.21 (0.99-1.47); P_trend = 0.04]. Furthermore, replacing 1 egg (50 g d^-1) with an equal amount of total dairy products was related to 11% lower colorectal polyp prevalence [OR (95% CI): 0.89 (0.80-0.99); P = 0.03]. In summary, higher egg consumption was correlated with a higher polyp prevalence among the Chinese population at a high risk of CRC, which was ascribed to the high content of dietary cholesterol in eggs. Besides, individuals with the highest dietary cholesterol tended to have a higher polyp prevalence. Reducing the consumption of eggs and replacing eggs with total dairy products as alternative protein sources may prevent the occurrence of polyps in China.

Comparison of Colonoscopy, Fecal Immunochemical Test, and Risk-Adapted Approach in a Colorectal Cancer Screening Trial (TARGET-C)

BACKGROUND & AIMS

The screening yield and related cost of a risk-adapted screening approach compared with established screening strategies in population-based colorectal cancer (CRC) screening are not clear.

METHODS

We randomly allocated 19,373 participants into 1 of the 3 screening arms in a 1:2:2 ratio: (1) one-time colonoscopy (n = 3883); (2) annual fecal immunochemical test (FIT) (n = 7793); (3) annual risk-adapted screening (n = 7697), in which, based on the risk-stratification score, high-risk participants were referred for colonoscopy and low-risk ones were referred for FIT. Three consecutive screening rounds were conducted for both the FIT and the risk-adapted screening arms. Follow-up to trace the health outcome for all the participants was conducted over the 3-year study period. The detection rate of advanced colorectal neoplasia (CRC and advanced precancerous lesions) was the main outcome. The trial was registered in the Chinese Clinical Trial Registry (number: ChiCTR1800015506).

RESULTS

In the colonoscopy, FIT, and risk-adapted screening arms over 3 screening rounds, the participation rates were 42.4%, 99.3%, and 89.2%, respectively; the detection rates for advanced neoplasm (intention-to-treat analysis) were 2.76%, 2.17%, and 2.35%, respectively, with an odds ratio (OR)colonoscopy vs FIT of 1.27 (95% confidence interval [CI]: 0.99-1.63; P = .056), an ORcolonoscopy vsrisk-adapted screening of 1.17 (95% CI, 0.91-1.49; P = .218), and an ORrisk-adapted screeningvs FIT of 1.09 (95% CI, 0.88-1.35; P = .438); the numbers of colonoscopies needed to detect 1 advanced neoplasm were 15.4, 7.8, and 10.2, respectively; the costs for detecting 1 advanced neoplasm from a government perspective using package payment format were 6928 Chinese Yuan (CNY) ($1004), 5821 CNY ($844), and 6694 CNY ($970), respectively.

CONCLUSIONS

The risk-adapted approach is a feasible and cost-favorable strategy for population-based CRC screening and therefore could complement the well-established one-time colonoscopy and annual repeated FIT screening strategies. (Chinese Clinical Trial Registry; ChiCTR1800015506).

Cross-sectional and longitudinal associations between body flexibility and sarcopenia

BACKGROUND

The associations between body flexibility and sarcopenia were not well understood. This study aimed to explore the cross-sectional and longitudinal associations of flexibility with sarcopenia.

METHODS

Our study selected participants aged 50-80 from the WELL-China cohort and the Lanxi cohort. Participants from the urban area of the Lanxi cohort were followed up 4 years later. Body flexibility was measured by the sit-and-reach test. Muscle mass was evaluated by dual-energy X-ray absorptiometry. Muscle strength was evaluated using handgrip strength. Sarcopenia was defined as having both low muscle mass and low muscle strength. We used multivariable logistic regressions to assess the cross-sectional associations of body flexibility with low muscle mass, low muscle strength and sarcopenia. We also used multivariable logistic regressions to explore the associations of baseline flexibility and 4-year changes in flexibility with incident low muscle mass, low muscle strength and sarcopenia.

RESULTS

A total of 9453 participants were enrolled in the cross-sectional study, and 1233 participants were included in the longitudinal analyses. In the cross-sectional analyses, compared with low body flexibility, high body flexibility was inversely associated with low muscle mass (odds ratio [OR], 0.58; 95% confidence interval [CI], 0.50-0.68; P < 0.001), low muscle strength (OR, 0.62; 95% CI, 0.55-0.69; P < 0.001) and sarcopenia (OR, 0.52; 95% CI, 0.41-0.65; P < 0.001), and these associations did not differ in different age groups, sex or physical activity levels. In the longitudinal analyses, compared with participants with low body flexibility, participants with high body flexibility had lower risk of the incident low muscle strength (OR, 0.53; 95% CI, 0.38-0.74; P < 0.001) and sarcopenia (OR, 0.36; 95% CI, 0.21-0.61; P < 0.001), but not incident low muscle mass (OR, 0.59; 95% CI, 0.33-1.06; P = 0.076). Every 1-cm increase in flexibility during 4 years was associated with reduced risk of incident low muscle mass (OR, 0.96; 95% CI, 0.93-1.00; P = 0.025), low muscle strength (OR, 0.96; 95% CI, 0.94-0.98; P = 0.002) and sarcopenia (OR, 0.96; 95% CI, 0.93-0.99; P = 0.007).

CONCLUSIONS

High flexibility was associated with reduced risk of incident low muscle strength and sarcopenia. Increases in flexibility were associated with reduced risk of incident low muscle mass, low muscle strength and sarcopenia. Flexibility exercises and monitoring the dynamic change of flexibility might be helpful in preventing sarcopenia among adults aged 50 years or over.

Analysis of SOD1 Variants in Chinese Patients with Familial Amyotrophic Lateral Sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease, and genetic contributors exert a significant role in the complicated pathogenesis. Identification of the genetic causes in ALS families could be valuable for early diagnosis and management. The development of potential drugs for patients with genetic defects will shed new light on ALS therapy.

AIM

To identify causative variants in three Chinese families with familial ALS (FALS), reveal the pathogenic mechanism, and look for the targeted drug for ALS.

DESIGN AND METHODS

Whole-exome sequencing and bioinformatics were used to perform genetic analysis of the ALS families. Functional analysis was performed to study the variants' function and search for potential drug targets.

RESULTS

Three heterozygous missense variants of the SOD1 gene were identified in families with FALS. The clinical manifestations of these patients include spinal onset, predominant lower motor neurons presentation, and absence of cognitive involvement. Functional analysis showed that all three SOD1 variants led to increased reactive oxygen species (ROS) levels, reduced cell viability, and formation of cytoplasmic aggregates. Remarkably, the decreased cell viability induced by variants was rescued after treatment with the ROS inhibitor N-acetylcysteine.

CONCLUSIONS

This study identified three SOD1 variants in three families with FALS. The variant SOD1 toxicity was associated with oxidative damage and aggregation, and N-acetylcysteine could rescue the decreased cell viability induced by these variants. Our findings support a pathogenic role for ROS in SOD1 deficiencies, and provide a potential drug N-acetylcysteine for ALS therapy, especially in SOD1-patients with limb onset.

[The effect of Helicobacter pylori infection on duodenal bulbar microbiota in children with duodenal ulcer]

Objective: To investigate the characteristics of duodenal bulbar microbiota in children with duodenal ulcer and Helicobacter pylori (Hp) infection. Methods: This prospective cohort study enrolled 23 children with duodenal ulcers diagnosed by gastroscopy who were admitted to the Children's Hospital of Zhejiang University School of Medicine due to abdominal pain, abdominal distension, and vomiting from January 2018 to August 2018. They were divided into Hp-positive and Hp-negative groups according to the presence or absence of Hp infection. Duodenal bulbar mucosa was sampled to detect the bacterial DNA by high-throughput sequencing. The statistical difference in α diversity and β diversity, and the relative abundance in taxonomic level between the two groups were compared. Microbial functions were predicted using the software PICRUSt. T-test, Rank sum test or χ² test were used for comparison between the two groups. Results: A total of 23 children diagnosed with duodenal ulcer were enrolled in this study, including 15 cases with Hp infection ((11.2±3.3) years of age, 11 males and 4 females) and 8 cases without Hp infection ((10.1±4.4) years of age, 6 males and 2 females). Compared with Hp-negative group, the Hp-positive group had higher Helicobacter abundance (0.551% (0.258%, 5.368%) vs. 0.143% (0.039%, 0.762%), Z=2.00, P=0.045) and lower abundance of Fusobacterium, Streptococcus and unclassified- Comamonadaceae (0.010% (0.001%, 0.031%) vs. 0.049% (0.011%, 0.310%), Z=-2.24, P=0.025; 0.031% (0.015%, 0.092%) vs. 0.118% (0.046%, 0.410%), Z=-2.10, P=0.036; 0.046% (0.036%, 0.062%) vs. 0.110% (0.045%, 0.176%), Z=-2.01, P=0.045). Linear discriminant analysis (LDA) effect sized showed that at the genus level, only Helicobacter was significantly enriched in Hp-positive group (LDA=4.89, P=0.045), while Streptococcus and Fusobacterium significantly enriched in Hp-negative group (LDA=3.28, 3.11;P=0.036,0.025, respectively). PICRUSt microbial function prediction showed that the expression of oxidative phosphorylation and disease-related pathways (pathways in cancer, renal cell carcinoma, amoebiasis, type 1 diabetes mellitus) in Hp-positive group were significantly higher than that in Hp-negative group (all P<0.05), while the expression of pathways such as energy metabolism and phosphotransferase system pathways were significantly lower than that in Hp-negative group (all P<0.05). Conclusion: In children with Hp-infected duodenal ulcers, the mucosal microbiota of the duodenal bulb is altered, characterized by an increased abundance of Helicobacter and a decreased abundance of Clostridium and Streptococcus, and possibly alters the biological function of the commensal microbiota through specific metabolic pathways.

The Reaction Kinetics and Mechanism of Catalytic Decomposition of Hydrazine nitrate on Ru/C Catalyst in Nitric Acid Solutions

Catalytic decomposition of hydrazine nitrate is a very important research topic in environmental protection field. Herein, we used Ru/C catalyst for decomposition of hydrazine nitrate in HNO3, and the reaction...

[The value of CMR high-risk attributes in predicting ventricular remodeling in ST-segment-elevation myocardial infarction patients with mildly reduced or preserved ejection fraction]

Objective: To evaluate the predictive value of a multiparametric cardiac magnetic resonance (CMR) approach for ventricular remodeling in ST-segment-elevation myocardial infarction (STEMI) patients with mildly reduced or preserved left ventricular ejection fraction (LVEF). Methods: This study is a prospective cohort study. STEMI patients with acute LVEF>40% after primary percutaneous coronary intervention (PCI) in Beijing Anzhen Hospital from October 2019 to September 2021 were enrolled. All patients received acute (3-7 days) and follow-up (3 months) CMR post-PCI. According to absence or presence of ventricular remodeling, patients were divided into ventricular remodeling group and non-ventricular remodeling group. Basic clinical characteristics and CMR indicators were analyzed and compared between the two groups. Logistic regression and receiver operating characteristic (ROC) curves were used to explore the predictive performance of CMR high-risk attributes for ventricular remodeling in STEMI patients with mildly reduced or preserved LVEF. The predictive value of combining multiple high-risk characteristics of CMR for ventricular remodeling was analyzed and compared with the traditional clinical risk factor model. Results: A total of 123 STEMI patients were enrolled (aged (57.1±11.1) years, 102 (82.9%) males). There were 97 cases (78.9%) patients in the non-ventricular remodeling group and 26 cases (21.1%) in the ventricular remodeling group. After adjustment for clinical risk factors, stroke volume<51.6 ml, global circumferential strain>-13.7%, infarct size>39.2%, microvascular obstruction>0.5%, and myocardial salvage index<43.9 were independently associated with ventricular remodeling in STEMI patients with mildly reduced or preserved LVEF. The incidence of ventricular remodeling increased with the increasing number of CMR high-risk attributes (P<0.01). The number of CMR high-risk attributes ≥3 was an independent predictor of adverse remodeling (adjusted OR=5.95, 95 CI%: 2.25-15.72, P<0.01) in STEMI patients with mildly reduced or preserved LVEF. Furthermore, the number of CMR high-risk attributes had incremental predictive value over baseline clinical risk factors (area under curve: 0.843 vs. 0.696, P<0.01). Conclusions: In STEMI patients with mild reduced or preserved LVEF, 5 CMR characteristics are associated with ventricular remodeling. The combination of ≥3 CMR high-risk characteristics is an independent predictor of ventricular remodeling, which has incremental predictive value beyond traditional risk factors in this patient cohort.

The effect of feeding location on the continuous precipitation of Pu(IV) oxalate in a vortex precipitator

The effects of feeding location on crystals size and distribution, precipitation percentage of Pu(IV) oxalate were investigated in a vortex continuous precipitator when the apparent average residence time was 25 min at 50 °C. The results showed that when oxalic acid was into the free vortex zone and Pu(IV) nitrate solution was into the forced vortex one, the VMD of the particles near the outlet of the precipitator increased from 36.8 ± 1.2 µm to 45.8 ± 2.1 µm, the precipitation percentage of Pu(IV) oxalate from 97.90% ± 1.0–99.79% ± 0.05%, compared with another feeding location, both oxalic acid and Pu(IV) nitrate solution into the forced vortex zone. The two feeding methods could both prevent Pu(IV) oxalate nuclei contacting the inner wall of the precipitator during nucleation. The results showed agglomeration happened during crystals growth even under stirring. Both local supersaturations and agglomeration decided particles size distribution and the average size of Pu(IV) oxalate.

[Bilateral anterior lenticonus: a case report]

A patient complained of ophthalmology with poor vision in both eyes for more than 30 years and aggravation for more than 2 years. The central anterior lens capsule was found to have a conical protrusion under a slit-lamp microscope after pupil dilation in both eyes. The diagnosis was bilateral cataract and congenital anterior lenticonus. Phacoemulsification cataract extraction combined with intraocular lens implantation was performed. The visual acuity in both eyes was significantly better after surgery.

P-447 Enhancing oxygen availability in the dynamic culture of bovine ovarian cortical tissue improves the yield of secondary follicles

Study question

Does enhancing oxygen availability during dynamic in vitro culture of bovine ovarian cortical tissue (BOCT) improve follicle growth and health?

Summary answer

Enhancing oxygen availability during dynamic in vitro culture of BOCT in perifusion bioreactors (PB) does improve follicle health and yield to secondary follicles

What is known already

Oxygen availability has been demonstrated to represent a key factor in follicle health and growth during in vitro culture of bovine and human ovarian cortical tissue (HOCT) under static culture conditions. Disruption of solutes gradients and application of physiological fluid mechanical stress, through in vitro dynamic culture of HOCT in a newly designed perifusion bioreactor have been shown to further enhance follicle growth and health. As it shows striking similarities with human, bovine folliculogenesis is considered a valuable model to study follicle growth in vitro

Study design, size, duration

Bovine ovaries from animals aged 8-24 months were collected at slaughterhouse. In each experiment (n = 3), BOCT strips from the same ovary were cultured for 6 days in perifusion bioreactors (PB, dynamic culture) and conventional dishes (CD, static culture). Culture outcome in static culture was analysed and compared to two bioreactor configurations in which medium oxygenation was kept low by using a standard tube reservoir (StPB) or was enhanced by using a gas-permeable dish reservoir (PB+O2).

Participants/materials, setting, methods

Slices of BOCT 0.5mm thick were cut with a tissue slicer and chopped into 1x1mm strips. In each experiment, fresh (D0) and cultured tissue (groups of ten strips) were analyzed. Follicle stages and health were assessed by histology (hematoxylin-eosin staining). Follicle viability was estimated by labelling with live-dead far-red and propidium iodide followed by clearing before analysis at the confocal laser scanning microscope.

Main results and the role of chance

Overall, 2417 follicles were analyzed (histology, 1476; viability, 941). At day 0 most follicles were primordial (primordial, 88.7%; primary, 10.6%; secondary, 0.7%), and had good quality (grade 1-2, 92.2%; grade 3, 7.8%), and high viability (91.8%). At day 6, follicle growth and health in StPB was superior than in CD (StPB vs CD - staging: primordial, 6.8 vs 16.3, P &lt; 0.01; primary, 70.7 vs 74.1, NS; secondary, 22.5 vs 9.6%, P &lt; 0.01; grading: grade 1 + 2, 71.4 vs 44.8, P &lt; 0.01; grade 3, 28.6 vs 55.2%, P &lt; 0.01). Dynamic culture in StPB better-preserved follicle viability compared to static culture in CD (StPB vs CD: 77.75 vs 64.9%, P &lt; 0.01). Enhancing oxygen availability during dynamic culture increased follicle progression and viability (PB+O2 vs StPB - staging: primordial, 5.1 vs 6.8, NS; primary, 65.4 vs 70.7, NS; secondary, 29.5 vs 22.5%, P &lt; 0.05; viability - 92 vs 77.75, P &lt; 0.01). Overall, the obtained results demonstrate that i) disruption of stagnant layers of medium and application of shear stress to BOCT through dynamic culture improves follicle activation, growth and health; ii) enhancing oxygen availability by means of a gas-permeable medium reservoir further increases follicle progression and viability.

Limitations, reasons for caution

Although the bovine is considered a reliable model for human folliculogenesis, the study should be validated on human ovarian tissue.

Wider implications of the findings

A limiting step in the in vitro production of mature oocytes starting from primordial follicles is the low yield of secondary follicles after organ culture. The adoption of a newly designed dynamic bioreactor and modulation of oxygen availability could represent a valuable tool for multistep in vitro folliculogenesis.

Trial registration number

none

Unnecessary caesarean section delivery in rural China: exploration of relationships with full-term gestational age and early childhood development

INTRODUCTION

Gestational age at delivery is reportedly associated with cognitive and non-cognitive development in early childhood. Delivery at an earlier full-term gestational age has been associated with an increased rate of caesarean section (C-section) delivery; the high rate of C-section delivery in China implies that the rate of medically unnecessary C-section delivery is also high. This study investigated the relationships of medically unnecessary C-section delivery with full-term gestational age and early childhood development in rural China.

METHODS

We conducted a survey of 2765 children (aged 5-24 months) who resided in 22 national designated poverty counties. Primary caregivers were interviewed to collect information regarding child and household characteristics (including the child's gestational age), each child's delivery method, and reasons for C-section delivery (if applicable). The children were assessed using the Bayley Scales of Infant Development. Developmental outcomes were compared among gestational age-groups; regression analyses were used to assess relationships among medically unnecessary C-section delivery, gestational age, and developmental outcomes.

RESULTS

Overall, 56.2% of children were born at ≤39 weeks of gestation. Among C-section deliveries, 13.1% were medically necessary and >40% could clearly be classified as medically unnecessary. Repeat C-section was the most common reason given for medically unnecessary C-section delivery. For each 1-week increase in full-term gestational age, cognition scale scores increased by 0.62 points (P<0.01), language scale scores increased by 0.84 points (P<0.01), and motor scale scores increased by 0.55 points (P<0.05). Medically unnecessary Csection delivery was significantly associated with lower full-term gestational age.

CONCLUSION

Higher full-term gestational age was significantly associated with better childhood developmental outcomes, indicating that medically unnecessary C-section delivery may negatively influence early childhood development.

POS0218 DECREASED miR-122-5p IN NEUTROPHIL-DERIVED EXOSOMES ATTENUATED IMMUNOREGULATORY FUNCTION ON MACROPHAGES BY TARGETING IRF5 EXPRESSION IN BEHCET’S DISEASE

Background

Behçet’s disease (BD) is a chronic systemic vasculitis characterized by the overactivation of neutrophils and macrophages. Exosomes are membrane-derived vesicles that mediate intercellular communications and neutrophil-derived exosomes account for the major portion of serum exosomes in BD. However, the role of neutrophil-derived exosomes in BD remains unknown.

Objectives

1) To investigate the production of exosomes by BD neutrophils; 2) To elucidate the regulation of macrophage by BD neutrophil-derived exosomes; 3) To explore the mechanism of immunoregulatory functions of BD neutrophil-derived exosomes.

Methods

BD and healthy control (HC) neutrophil-derived exosomes were extracted and quantified. Human monocyte-derived macrophages (HMDM) were stimulated with BD and HC neutrophil-derived exosomes, and TNF-α and IL-6 production were examined. Differently expressed miRNAs in BD neutrophil-derived exosomes were analyzed using miRNA sequencing. LPS-induced HMDM were treated with miRNA mimics or inhibitors, and TNF-α and IL-6 production were detected. miRNA was overexpressed in macrophages, and RNA sequencing was performed to analyze regulating pathways. Dual-luciferase assays were performed to confirm miRNA-mRNA interaction.

Results

BD neutrophils produced a significantly lower level of exosomes than HC ones. Both BD and HC neutrophil-derived exosomes suppressed TNF-α and IL-6 production by macrophages, but to a lesser extent by BD neutrophil-derived exosomes. Six downregulated miRNAs were presented in BD neutrophil-derived exosomes, including miR-122-5p. miR-122-5p mimics inhibited IL-6 and TNF-α production while miR-122-5p inhibitor promoted IL-6 and TNF-α production by HMDMs. Overexpression of miR-122-5p attenuated TLR4 and IFN-β signaling. miR-122-5p directly targeted 3’UTR of IRF5, the TF regulating TLR4 pathway and autocrine of IFN-β, and downregulated IRF5 expression confirmed by dual luciferase assay. Knocking down IRF5 dampened IL-6 and TNF-α production in HMDMs.

Figure 1.

(A) Decreased production of BD neutrophil-derived exosomes. (B) Reduced suppression of macrophage activation by BD neutrophil-derived exosomes. (C) Differentially expressed miRNAs (downregulated) in BD neutrophil-derived exosomes. (D) miR-122-5p suppressed TLR4 and JAK-STAT signaling in HMDM. (E) miR-122-5p inhibited activation of HMDM. (F) miR-122-5p inhibited IRF5 expression in HMDM.

Conclusion

Our findings suggested the reduced production and immunoregulatory function of BD neutrophil-derived exosomes, mediated by lower levels of miR-122-5p in neutrophil-derived exosomes. Impaired BD neutrophil-derived exosomes might be implicated in the overactivation of macrophages in BD.

References

[1]Kolonics, Ferenc et al. Cells vol. 9,12 2718. 18 Dec. 2020,

Disclosure of Interests

None declared

Associations of 3-monochloropropane-1,2-diol and glycidol with prevalence of metabolic syndrome: Findings from Lanxi Nutrition and Safety Study

In this study, we investigated the association of 2,3-dihydroxypropyl mercapturic acid (DHPMA), a urinary biomarker of environmental and dietary exposure to 3-monochloropropane-1,2-diol and glycidol, with prevalent MetS in a Chinese middle-aged and elderly population. The urinary DHPMA concentrations were determined by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) analysis and further calibrated by the urinary creatinine content. MetS cases were defined by the Adult Treatment Panel III criteria for Asian-Americans of National Cholesterol Education Program (NCEP/ATPIII). Multivariate-adjusted modified Poisson regression models were used to analyze the associations between the urinary DHPMA concentrations and MetS prevalence. Of the 1613 participants aged 45-75 years, we documented 552 (34.2%) MetS cases. After adjustment for potential risk factors, the relative risks (95% confidence intervals) of MetS prevalence across the increasing quartiles of DHPMA concentrations were 1.14 (0.93-1.39), 1.29 (1.06-1.56), and 1.50 (1.25-1.80), respectively, compared with the lowest quartile. We also observed strong positive association between urinary DHPMA concentrations and hypertriglyceridemia prevalence (P < 0.001 for trend). These positive associations remained unchanged in the subgroups stratified by general demographic, dietary and behavioral risk factors. These results suggested that urinary DHPMA was associated with higher prevalence of MetS among Chinese elderly people.

Porous Copper-Loaded Zeolites for High-Efficiency Capture of Iodine from Spent Fuel Reprocessing Off-Gas

Capturing volatile radionuclide iodine produced in the nuclear industry is a crucial environmental issue. In previous studies, the principal efficient adsorbent for iodine capture was silver-containing zeolite. As silver-containing zeolites are expensive, alternate copper-loaded porous zeolites, including CuCl loaded NaY reduced by H₂ (denoted as H₂CuY) and CO (denoted as COCuY), were studied for iodine adsorption at moderate temperatures. The current work also discusses the influence of copper valency on iodine adsorption. Due to the copper sites and nanosized pore structure, H₂CuY and COCuY showed high iodine adsorption capacities of 450 and 219 mg/g, respectively. The iodine adsorption capacity of H₂CuY was higher than that of silver-loaded zeolites. Moreover, H₂CuY and COCuY adsorbed volatile iodine through a chemical mechanism involving the copper sites of different valencies, and the Cu⁰ was more effective in adsorbing iodine than Cu⁺. These copper-loaded zeolites with strong chemical interactions with iodine and high iodine adsorption capacities provided the possibility for iodine adsorption application in the nuclear industry.

Lattice dynamics of BaFe2Se3

This paper presents a study of the lattice dynamics in BaFe₂Se₃. We combined first-principle calculations, infrared measurements and a thorough symmetry analysis. Our study confirms thatPnmacannot be the space group of BaFe₂Se₃, even at room temperature. The phonons assignment requiresPmto be the BaFe₂Se₃space group, not only in the magnetic phase, but also in the paramagnetic phase at room temperature. This is due to a strong coupling between a short-range spin-order along the ladders, and the lattice degrees of freedom associated with the Fe-Fe bond length. This coupling induces a change in the bond-length pattern from an alternated trapezoidal one (as inPnma) to an alternated small/large rectangular one. Out of the two patterns, only the latter is fully compatible with the observed block-type magnetic structure. Finally, we propose a complete symmetry analysis of the BaFe₂Se₃phase diagram in the 0-600 K range.

Association of Meat Subtypes With Colorectal Polyp Prevalence: Finding From the Lanxi Pre-colorectal Cancer Cohort in China

Background

Although the detrimental effect of red meat on colorectal cancer (CRC) incidence has been extensively reported, no previous studies have comprehensively linked different meat subtypes with colorectal polyp occurrence. The aim was to assess the association of meat and subtypes with colorectal polyp prevalence for the high-risk CRC Chinese population. Besides, we also focused on the association according to sizes, subsites, and multiplicity of polyps.

Methods

High-risk CRC patients aged 40–80 years were enrolled into the Lanxi Pre-colorectal Cancer Cohort (LP3C) between March 2018 and December 2019. Cross-sectional analyses were conducted by using the baseline data from LP3C. A validated food frequency questionnaire (FFQ) was employed to collect dietary information. Odds ratios (ORs) and 95% confidence intervals (95% CIs) of colorectal polyp prevalence were estimated by multivariate logistic regression.

Results

2,064 colorectal polyp cases were identified among 6,783 eligible participants in the survey of LP3C (March 2018 and December 2019). Total meat intake was positively related to rectum polyp prevalence (P_{for trend} = 0.01) but was not linked to total colorectal polyps after multivariable adjustment. For meat subtypes, higher poultry consumption was significantly related to a higher polyp prevalence [OR_Q4vs.Q1 (95% CI): 1.20 (1.02–1.42); P_{for trend} = 0.03]. Processed red meat intake was linked to an increased small polyp prevalence (P_{for trend} = 0.03) while unprocessed red meat had a relation with a higher rectum polyp prevalence (P_{for trend} = 0.04). Furthermore, seafood intake had a significant association with a higher multiple polyp prevalence [OR_Q4vs.Q1 (95% CI): 1.70 (1.31–2.21); P_{for trend} < 0.001].

Conclusion

The finding was that poultry meat consumption was related to a higher polyp prevalence. Besides, total meat consumption, processed and unprocessed red meat consumption, seafood consumption had a positive relation with certain polyp subtypes prevalence. Generally recommending reducing total meat consumption, including poultry, processed and unprocessed red meat, and seafood intake, may prevent colorectal polyps.

Catalytic decomposition of hydroxylamine nitrate and hydrazine nitrate using Ru/ZSM-5 catalyst under mild reaction conditions

Hydroxylamine nitrate and hydrazine nitrate are dangerous explosives and toxic chemicals. Catalytic decomposition is an efficient way for disposal of these chemicals. In the current work, a Ru/ZSM-5 catalyst has been fabricated and evaluated for the decomposition of hydroxylamine nitrate and hydrazine nitrate in 1.0 mol L⁻¹ HNO₃. The hydroxylamine nitrate and hydrazine nitrate can be thoroughly decomposed under 80 °C. And the Ru/ZSM-5 catalyst can be separated from the reaction mixture and reused at least 130 times with stable catalytic performance. Easy operation, less solid waste generation, and a simple catalytic device make the strategy reported here practical, environmentally friendly, and economically attractive.

The Ru/ZSM-5 catalyst was shown to be an efficient heterogeneous catalyst for decomposition of hydroxylamine nitrate and hydrazine nitrate. The catalyst could be recovered by filtration and reused, showing good potential for industrial application.

A Brucella Omp16 Conditional Deletion Strain Is Attenuated in BALB/c Mice

Brucella spp. are facultative intracellular pathogens that invade, survive and proliferate in numerous phagocytic and non-phagocytic cell types, thereby leading to human and animal brucellosis. Outer membrane proteins (Omps) are major immunogenic and protective antigens that are implicated in Brucella virulence. A strain deleted of the omp16 gene has not been obtained which suggests that the Omp16 protein is vital for Brucella survival. Nevertheless, we previously constructed an omp16 conditional deletion strain of Brucella, ΔOmp16. Here, the virulence and immune response elicted by this strain were assessed in a mouse model of infection. Splenomegaly was significantly reduced at two weeks post-infection in ΔOmp16-infected mice compared to infection with the parental strain. The bacterial load in the spleen also was significantly decreased at this post-infection time point in ΔOmp16-infected mice. Histopathological changes in the spleen were observed via hematoxylineosin staining and microscopic examination which showed that infection with the ΔOmp16 strain alleviated spleen histopathological alterations compared to mice infected with the parental strain. Moreover, the levels of humoral and cellular immunity were similar in both ΔOmp16-infected mice and parental strain-infected mice. The results overall show that the virulence of ΔOmp16 is attenuated markedly, but that the immune responses mediated by the deletion and parental strains in mice are indistinguishable. The data provide important insights that illuminate the pathogenic strategies adopted by Brucella.

A WC/WO star exploding within an expanding carbon-oxygen-neon nebula

The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars¹ emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars^2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion⁴. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients^5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.

Utilizing phenotypic characteristics of metastatic brain tumors to improve the probability of detecting circulating tumor DNA from cerebrospinal fluid in non-small-cell lung cancer patients: development and validation of a prediction model in a prospective cohort study

Background

Circulating tumor DNA (ctDNA) in cerebrospinal fluid (CSF) has become a promising surrogate for genomic profiling of central nervous system tumors. However, suboptimal ctDNA detection rates from CSF limit its clinical utility. Thus precise screening of suitable patients is needed to maximize the clinical benefit.

Patients and methods

Between February 2017 and December 2020, 66 newly diagnosed non-small-cell lung cancer (NSCLC) patients with brain parenchymal metastases were prospectively enrolled as a training cohort and 30 additional patients were enrolled as an external validation cohort. CSF samples and matched primary tumor tissues were collected before treatment and subjected to next-generation sequencing (NGS). The imageological characteristics of patients’ brain tumors were evaluated by radiologists using enhanced magnetic resonance imaging images. The clinical and imageological characteristics were evaluated by complete subsets regression, Akaike information criteria, and Bayesian information criteria methods to establish the prediction model. A nomogram was then built for CSF ctDNA detection prediction.

Results

The somatic mutation detection rate of genes covered by our targeted NGS panel was significantly lower in CSF ctDNA (59.09%) than tumor tissue (91.84%). The T_size (diameter of the largest intracranial lesion) and LVD_min (minimum lesion–ventricle distance for all intracranial lesions) were significantly associated with positive CSF ctDNA detection, and thus, were selected to establish the prediction model, which achieved an area under the ROC curve (AUC) of 0.819 and an accuracy of 0.800. The model’s predictive ability was further validated in the independent external cohort (AUC of 0.772, accuracy of 0.767) and by internal cross-validation. The CSF ctDNA detection rate was significantly improved from 58.18% (32/55) to 81.81% (27/33) in patients after model selection (P = 0.022).

Conclusions

This study developed a regression model to predict the probability of detecting CSF ctDNA using the phenotypic characteristics of metastatic brain lesions in NSCLC patients, thus, maximizing the benefits of CSF liquid biopsies.

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Intracranial tumor size and distance to nearest ventricle were significantly correlated with positive CSF ctDNA detection.

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A prediction model incorporating T_size and LVD_min was developed and validated to evaluate the odds of CSF ctDNA positivity.

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The CSF ctDNA detection rate was significantly improved in patients after model selection.