AIM:To investigate the mechanism by which N6-methyladenosine(m6A)methylase methyltrans-ferase-like protein 3(METTL3)regulates the differentiation of human bone marrow mesenchymal stem cells(MSCs)into adipocytes in vitro.METHODS:Lentiviral vectors of METTL3,AKT serine/threonine kinase 1(AKT1),peroxisome pro-liferator-activated receptor γ(PPARγ)and YTH m6A RNA binding protein F2(YTHDF2)were constructed to package lentiviral particles and used to infect MSCs.A human bone MSC adipogenic differentiation kit was used to induce the MSCs into adipocytes.Additionally,the adipocytes were stained by oil red O.The recombinant vector of METTL3 mutant was constructed using molecular cloning to confirm the regulatory effect of the key site of m6A in METTL3 on the target genes.Actinomycin D was applied to MSCs with overexpression of YTHDF2 to evaluate the effect of YTHDF2 recognition on the mRNA and protein expression of AKT1.The RNA pull-down assay combined with silver staining and Western blot were used to detect the binding of potentially methylated fragments to recognized proteins.RESULTS:METTL3 inhibited the adipogenesis of MSCs in an AKT1/PPARγ-dependent manner,and mediated the protein expression of AKT1 in an m6A-YTHDF2-dependent manner.YTHDF2 recognized and bound to coding sequence(CDS)of m6A-AKT1,and reduced its expression,which inhibited the adipogenesis of MSCs.CONCLUSION:The m6A methylase METTL3 regulates the adipo-genic differentiation of human bone marrow MSCs through YTHDF2/AKT1/PPARγ,providing a theoretical basis for the identification of new targets for acute myeloid leukemia treatment from the perspective of tumor microenvironment.

Objective: To understand the prevalence of HIV testing and related factors among young students who had sex in Guangdong Province, in order to provide evidence for relevant education programs and HIV testing promotion in young students. Methods: From September to December 2022, a convenient sampling method was used to select 48 749 young students from 16 universities and mechanic colleges in 6 cities including Guangzhou, Shantou, Maoming, Huizhou, Dongguan, and Zhongshan in Guangdong Province for online questionnaire survey. A total of 2 971 students who ever had sexual experiences were screened out, and the HIV testing situation and related factors were investigated by using the questionnaire designed by AIDS Prevention and Education Project for College Students of China STD and AIDS Prevention Association.The influencing factors of HIV testing were analyzed using Chi square test and multiple Logistic regression model. Results: Among students who had sexual experiences, 11.92% (354/2 971) were tested for HIV. The results of multivariate Logistic regression analysis showed that among young sexual students, using psychoactive substances during sexual activity in the last 1 year ( OR =7.70), having first sex with the same sex ( OR =3.87), having commercial sex ( OR =2.37), having heard of PEP ( OR =2.20), having a high level of self assessed understanding of HIV testing ( OR =1.73), inconsistent use of condoms ( OR =1.56), being aware of HIV infection ( OR =1.53), being aware of HIV knowledge ( OR =1.51) were more likely to test for HIV, and females ( OR =0.39) were less likely to test for HIV ( P < 0.05). Conclusions The proportion of HIV testing is low among sexually active young students in Guangdong Province. Targeted interventions should be tailored to promote HIV testing coverage.

Objective:To explore high-risk sexual behaviors of HIV/AIDS and related factors in young students in Guangzhou.Methods:A cross-sectional survey was conducted in 5 different types of Guangzhou colleges by convenience sampling with minimum number of classes per grade and 600 samples per school from September to November 2021. The R 4.2.2 software was used to consolidate databases. Simultaneously, a logistic regression model and a decision tree algorithm model, stratifying by whether sexual behaviors had occurred before, were constructed. In each layer, the prediction performance of the two models was evaluated through area under receiver operating characteristic and the confusion matrix, and then the model with high prediction performance was retained.Results:A total of 7 346 students were surveyed. The proportion of the respondents reporting sexual experience were 9.08% (667/7 346), in whom 26.24% (175/667) had risky sexual activity in the past year. The decision tree algorithm model performs well in predicting whether high-risk sexual behaviors have occurred in the past year. When the complexity parameter value is 0.018, and nsplit reaches 4, which means there are 5 leaf nodes in the model, the cross error of the tree will be the smallest. The first best grouping variable in the decision tree was whether to use condoms throughout the first sexual behavior. If condoms were used at their sexual debut, but homosexual practices have occurred in the past year, the probability of risky sexual behavior will increase. If homosexual practices have not occurred in the past year, but the age of sexual debut was below 18 years old while the period of HIV education was after high school, the probability of risk sexual behavior will also increase.Conclusions:AIDS-related risky behaviors of young students still deserved attention. The experience of sexual debut and whether AIDS-related health education has been received before the sexual debut were significant predictors for the occurrence of high-risk sexual behavior. The decision tree algorithm model has particular applicability for predicting and screening potential risk populations.

Epstein-Barr virus (EBV) associated post-transplant lymphoproliferative disorders (PTLD) are one of the most severe complications after hematopoietic stem cell transplantation (HSCT). This study includes 31 cases of aplastic anemia (AA) patients who developed PTLD after haploidentical transplantation, summarizing their clinical characteristics and categorizing them into either rituximab monotherapy group or combination therapy group based on whether their condition improved by 1 log after a single dose of rituximab. The incidence of PTLD after HSCT in children with AA was 10.16%, and the incidence of PTLD in patients with age >10 years was significantly increased ( χ2=11.336, P=0.010). Of the 31 patients, 27 were clinically diagnosed and 4 were pathologically confirmed. Finally, 15 patients were classified into the rituximab treatment group and 15 patients into the combination treatment groups. Finally three patients died, and the 2-year overall survival rate was (89.7±5.6) %. Standard pre-treatment protocols and EBV reactivation are risk factors affecting the prognosis of PTLD. There was no statistically significant difference in the impact of the two treatment schemes on prognosis.

Objective:To investigate the efficacy and safety of venetoclax combined with the decitabine, cytarabine, and homoharringtonine (HHT) regimen and donor lymphocyte infusion (DLI) for the preventive and salvage therapy of pediatric acute myeloid leukemia (AML) /myelodysplastic syndrome (MDS) after allogeneic hematopoietic stem cell transplantation (HSCT) .Methods:A total of 29 relapsed pediatric/minimal residual disease-positive AML after HSCT were recruited at the Peking University Institute of Hematology from January 1, 2021, to June 1, 2023. They were treated with the above combination regimen and administered with DLI after 24-48 hours at the end of chemotherapy, and the treatment response and adverse reactions were regularly assessed.Results:The overall response rate (ORR) was 75.8%, CR rate was 88.9% (8/9) in the hematologic relapse group, and MRD negativity rate was 61.1% (11/18) in the MRD-positive group. The incidence of agranulocytosis, anemia, and thrombocytopenia with a classification above grade 3 were 100%, 82.7%, and 100%, respectively. The median time of the granulocyte deficiency period was 15 days. Acute graft-versus-host diseases (aGVHD) with a classification of grades Ⅲ-Ⅳ occurred in 11.1% of the patients after DLI, while moderate or severe cGVHD occurred in 7.4% of the patients. The single risk factor for ORR was MNC counts of less than 10×10 8/kg, and the relapse occurred within 100 days. At a median follow-up of 406 days, the 1-year OS was 65%, and the 1-year OS was 57% in the group with no reaction ( P=0.164) compared with 71% in the group who had an overall reaction. Conclusion:The combined regimen based on the DAC, VEN, and modified HA regimen showed a high response rate in the salvage therapy for pediatric AML after the relapse of HSCT. However, bridging to transplantation should be performed immediately after remission to result in a long survival rate.

Background::The correlation between metals and hypertension, such as sodium, zinc, potassium, and magnesium, has been confirmed, while the relationship between aluminum and hypertension is not very clear. This study aimed to evaluate the correlation between plasma aluminum and hypertension in electrolytic aluminum workers by the Bayesian networks (BN).Methods::In 2019, 476 male workers in an aluminum factory were investigated. The plasma aluminum concentration of workers was measured by inductively coupled plasma mass spectrometry. The influencing factors on the prevalence of hypertension were analyzed by the BN.Results::The prevalence of hypertension was 23.9% in 476 male workers. The risk of hypertension from plasma aluminum in the Q2, Q3, and Q4 groups was 5.20 (1.90-14.25), 6.92 (2.51-19.08), and 7.33 (2.69-20.01), respectively, compared with that in the Q1 group. The risk of hypertension from the duration of exposure to aluminum of >10 years was 2.23 (1.09-4.57), compared without aluminum exposure. Area under the curve was 0.80 of plasma aluminum and the duration of exposure to aluminum was based on covariates, indicating that aluminum exposure had important predictive value in the prevalence of hypertension in the occupational population. The results of the study using the BN model showed that if the plasma aluminum of all participants was higher than Q4 (≥47.86 μg/L) and the participants were drinking, smoking, diabetes, central obesity, dyslipidemia, and aged >50 years, the proportion of hypertension was 71.2%.Conclusions::The prevalence of hypertension increased significantly with the increase of plasma aluminum level.

Background::The correlation between metals and hypertension, such as sodium, zinc, potassium, and magnesium, has been confirmed, while the relationship between aluminum and hypertension is not very clear. This study aimed to evaluate the correlation between plasma aluminum and hypertension in electrolytic aluminum workers by the Bayesian networks (BN).Methods::In 2019, 476 male workers in an aluminum factory were investigated. The plasma aluminum concentration of workers was measured by inductively coupled plasma mass spectrometry. The influencing factors on the prevalence of hypertension were analyzed by the BN.Results::The prevalence of hypertension was 23.9% in 476 male workers. The risk of hypertension from plasma aluminum in the Q2, Q3, and Q4 groups was 5.20 (1.90-14.25), 6.92 (2.51-19.08), and 7.33 (2.69-20.01), respectively, compared with that in the Q1 group. The risk of hypertension from the duration of exposure to aluminum of >10 years was 2.23 (1.09-4.57), compared without aluminum exposure. Area under the curve was 0.80 of plasma aluminum and the duration of exposure to aluminum was based on covariates, indicating that aluminum exposure had important predictive value in the prevalence of hypertension in the occupational population. The results of the study using the BN model showed that if the plasma aluminum of all participants was higher than Q4 (≥47.86 μg/L) and the participants were drinking, smoking, diabetes, central obesity, dyslipidemia, and aged >50 years, the proportion of hypertension was 71.2%.Conclusions::The prevalence of hypertension increased significantly with the increase of plasma aluminum level.

ObjectiveTo understand the serotype distribution and drug resistance of salmonella contaminated in commercially available food. MethodsSalmonella detection， including the serotypes， was conducted in food products sold in Pudong New Area from 2020 to 2022. The antimicrobial susceptibility test of 15 antibiotics was conducted by the broth microassay. ResultsA total of 118 salmonella strains were detected in 2 497 pieces of food， with a total detection rate of 4.7%. The dominant detection categories were poultry meat， livestock meat and aquatic products. The 118 salmonella strains could be divided into 24 serotypes， Salmonella enteritidis （26.4%）， Salmonella Typhimurium （16.2%） and Salmonella delpy （14.4%） were the main dominant types. Salmonella had the highest resistance rate to ampicillin （63.6%）， followed by tetracycline， chloramphenicol， cotrimoxazole and nalidixic acid. Among the three dominant serotypes， the multidrug resistance rate of Salmonella typhimurium was the highest （89.5%）， followed by Salmonella delpy （70.6%） and Salmonella enteritidis （61.3%）. ConclusionLivestock， poultry meat， and aquatic products are seriously contaminated by salmonella with diverse serotypes. The livestock meat is mainly contaminated by Salmonella typhimurium and Salmonella delpy， and the poultry meat is mainly contaminated by Salmonella enteritidis. The drug resistance spectrum is wide and the multi-drug resistance rate is high. Different from the livestock and aquatic isolates， poultry meat-derived strains have high tolerance to ampicillin， nalidixic acid and polymyxin， and carry certain potential food safety risks.

Objective:To predict and analyze the number of acute pancreatitis (AP) inpatients based on time series model, and to explore the predictive efficiency of the model.Methods:Clinical data of AP inpatients in the Affiliated Hospital of Southwest Medical University from January 2014 to December 2019 were collected. R software was used to collect the time series of AP inpatients, and the trend and seasonal characteristics of AP inpatients from 2014 to 2018 were analyzed. Furthermore, the autoregressive moving average (ARIMA) model was established through stationarity test, model ordering and model testing steps, and the best selected model was used to predict the monthly number of inpatients in 2019 to verify its prediction efficiency.Results:A total of 3 939 AP patients were included in the study. The most common etiology for AP was cholestrogenic (48.2%), followed by hyperacylglyceremia (36.3%). The peak age of hospitalization was from 40 to 60 years old. Time series analysis showed that the number of AP inpatients increased year by year. The highest peak of the disease was from February to March, followed by September to November; and there was seasonal variation and the incidence was relatively small in summer. The established original training set sequence did not pass the stationarity test ( P=0.061), so the ARIMA model was established after it was transformed into a stationarity sequence by first-order difference. According to the criterion of minimum AIC value, ARIMA(2, 1, 1)(1, 1, 1) 12 was selected as the best model. The model was used to predict the number of AP inpatients in 2019, showing that it could better fit the trend of onset time and had good short-term prediction effect. The mean root error and absolute error were 6.8790 and 4.7783, respectively. Conclusions:The number of AP inpatients increases year by year with seasonal changes. ARIMA model is effective in predicting the number of AP inpatients and can be used for short-term prediction.

Objective:To investigate the risk perception for risky behavior of HIV/AIDS infection among young students and to analyze the related influencing factors.Methods:A cross-sectional survey was conducted in 5 different types of Guangzhou colleges from September to November 2021, in which convenience sampling and a minimum number of classes per grade and 600 samples per school were used according to the national unity program. Disordered multi-classification logistic regression was used to construct a risk perception model and analyze influencing factors in different risk perception levels.Results:A total of 7 346 young students were surveyed, and most rated themselves at low risk of HIV/AIDS infections (90.58%, 6 654/7 346). A total of 89.10% (6 545/7 346) of subjects' perception of their HIV/AIDS infection risk was consistent with their risk behavior, while 10.90% (801/7 346) was inconsistent. Among those inconsistent subjects, 19.10% (153/801) showed underestimating their risk , while 80.90% (648/801) seen overestimating their risk. Disordered multi-classification logistic regression analysis showed that, after controlling for other factors, compared with the non-sexual group, respondents whose first sex age under 18 had a higher rate of underestimating their risk of infection ( OR=129.39, 95% CI: 73.28-228.48), as well as a higher rate of overestimated their risk of infection ( OR=1.76, 95% CI: 1.04-2.99). First sexual intercourse at age 18 or older was a risk factor for underestimating risk ( OR=70.56, 95% CI: 42.72-116.53), but was not statistically associated with overestimating risk. Being female, other school type, non-heterosexual orientation, and self-rated HIV-related knowledge as fair or no knowledge were risk factors for overestimating risk but were not statistically associated with underestimating risk. Conclusions:Overall, young students in universities of Guangzhou have a good risk perception of HIV/AIDS infection. Individual factors, education factors and sexual experience will influence students' risk perception of HIV/AIDS infection. Raising the awareness rate of HIV/AIDS knowledge and delaying the age of first sexual intercourse will improve the risk perception ability of young students.