ObjectiveTo prepare a recombinant PETase with a dual-catalytic-triad and to evaluate its efficiency in the biodegradation of polyethylene terephthalate （PET）. MethodsBased on the crystal structure of wild-type PETase， point mutations （T88H/L117D） were introduced via site-directed mutagenesis. The recombinant protein was prepared using prokaryotic expression and chromatography purification techniques. The enzymatic hydrolysis of the mutant PETase was assessed by relatively quantifying the products mono （2-hydroxyethyl） terephthalate （MHET） and terephthalic acid （TPA）. ResultsBoth wild-type and mutant PETases accumulated as inclusion bodies， accounting for approximately 20% of the total bacterial protein. After solubilization in urea， the proteins were eluted at 300 mmol/L imidazole during affinity chromatography purification， with concentrations of 1.824 and 1.833 mg/mL and purities of 83.11% and 84.32%， respectively. Subsequent anion-exchange chromatography yielded highly pure enzymes in the 200 mmol/L NaCl fraction： 2.776 mg/mL （96.86% purity） for the wild type and 1.967 mg/mL （95.13% purity） for the mutant. Following refolding， the final concentrations were 0.484 mg/mL for the wild type and 0.991 mg/mL for the mutant. Hydrolysis assays revealed that the mutant released MHET and TPA at （237.67±17.00）% and （197.33±12.01）% of the wild-type levels， respectively. ConclusionThe T88H/L117D dual-catalytic-triad PETase is successfully prepared and it significantly enhanced PET-degrading activity， thus， it′s a promising biocatalyst for PET bioremediation.

In March 2024, three male and two female specimens of the genus Lispe were intercepted on cargo ships inbound for Wan Zai Port under Gongbei Customs. Based on morphological characteristics and molecular analysis, the specimens were identified as Lispe pumila. In this study, we describe the morphological features, diagnostic characteristics, and geographical distribution of L. pumila, with the aim of providing a reference for the identification of this species when intercepted at ports.

With the rapid development of social economy and the continuous improvement of human living standard, the incidence, fatality and recurrence rates of cardiovascular disease (CVD) are increasing year by year, which seriously affects people's life and health. Conventional therapeutic drugs have limited improvement on the disability rate, so the search for new therapeutic drugs and action targets has become one of the hotspots of current research. In recent years, the therapeutic role of the natural compound rosmarinic acid (RA) in CVD has attracted much attention, which is capable of preventing CVD by modulating multiple signalling pathways and exerting physiological activities such as antioxidant, anti-apoptotic, anti-inflammatory, anti-platelet aggregation, as well as anti-coagulation and endothelial function protection. In this paper, the role of RA in the prevention of CVD is systematically sorted out, and its mechanism of action is summarised and analysed, with a view to providing a scientific basis and important support for the in-depth exploration of the prevention value of RA in CVD and its further development as a prevention drug.

Objective To investigate the application value of spectral CT multi-quantitative parameters combined with clinical characteristics in predicting high-risk gastroesophageal varices(GOV)in patients with liver cirrhosis.Methods The results of upper abdominal spectral CT enhancement and electronic gastroscopy in 112 patients diagnosed with liver cirrhosis were analyzed retrospec-tively,and the clinical data were collected.According to the gastroscopic manifestations,the patients were divided into high-risk GOV group(n=74)and low-risk GOV group(n=38).Univariate analysis was used to compare the spectral CT quantitative parameters and clinical characteristics between the two groups.Multivariate logistic regression analysis was used to screen the independent risk factors for high-risk GOV.R software was used to construct a nomogram model for predicting high-risk GOV,and the differentia-tion,calibration and clinical practicability of the prediction model were evaluated.Results The normalized iodine concentration(NIC)of liver left lobe,prothrombin time(PT),albumin(ALB)and liver function grading were independent risk factors for high-risk GOV(P＜0.05).The area under the curve(AUC)of receiver operating characteristic(ROC)curve of predicting high-risk GOV in nomo-gram model was 0.893.Calibration curve showed that the predicted results were basically consistent with the actual results.Decision curve analysis(DCA)showed that the prediction model had good clinical practicability.Conclusion The nomogram model based on NIC of liver left lobe,PT,ALB and liver function grading is helpful to predict patients with high-risk GOV in liver cirrhosis,and pro-vides a reference for clinical prevention and treatment of esophagogastric variceal bleeding(EVB).

Objective:To explore the application value of problem-based learning (PBL) combined with mini-clinical evaluation exercise (Mini-CEX) in the development of post competency for interns in the Department of Neurology.Methods:A total of 56 interns rotating at the Department of Neurology of The First Affiliated Hospital of Chongqing Medical University from June 2023 to January 2024 were enrolled as the study subjects. They were randomly divided into a control group and an experiment group using the random number table method, with 28 interns in each group. The control group received traditional methods including small lectures and teaching rounds, while the experimental group received the PBL teaching method combined with Mini-CEX. The teaching effectiveness was evaluated through theoretical assessments, practical skill evaluations, teacher and student satisfaction surveys, and Mini-CEX scale assessments conducted at the beginning, middle, and end of the rotation for the experimental group. The data were analyzed using SPSS 23.0 software. For continuous data, the independent-samples t test or Mann-Whitney U test was used for comparison between groups. The chi-square test was used for categorical data and the Kruskal-Wallis H test for repeated-measurement data. Results:The theoretical scores [(45.36±2.67) vs. (42.00±4.29), P<0.01] and practical skill scores [(45.11±2.53) vs. (42.39±4.53), P<0.01] were significantly higher in the experimental group compared to the control group. The Mini-CEX score of the experimental group at the end of the rotation was notably higher than that at the beginning of rotation ( P<0.05), and their abilities improved continuously. The satisfaction rates of teachers and students in the experimental group were 71.43% (20/28) and 67.86% (19/28), respectively, which were significantly higher than those in the control group [39.29% (11/28) and 35.71% (10/28), P<0.05]. Conclusions:The teaching model integrating PBL and Mini-CEX can effectively enhance the post competency of interns in the Department of Neurology, thus offering a new perspective for clinical undergraduate teaching.

Hepatitis B，an infectious disease caused by the hepatitis B virus（HBV），poses a severe threat to health by inducing acute and chronic hepatitis，cirrhosis，and liver cancer，thereby imposing heavy disease burden and psychological pressure to patients. In 1992，the average positive rate of hepatitis B surface antigen（HBsAg）in China was 9.75%，classifying the country as a high-prevalence area for hepatitis B. Since the mid-1980s，China has implemented a comprehensive prevention and control strategy centered on hepatitis B vaccination for newborns. This strategy encompasses measures such as blocking mother-to-child transmission，blood screening，control of healthcare-associated infections，prevention and control among key populations，and public education and awareness campaigns. After nearly four decades of efforts，the 2020 national hepatitis B seroepidemiological survey revealed a significant decline in China's overall HBsAg positive rate to 5.86%，with the positivity rate among children aged 1-4 years plummeting to just 0.30%. Compared with 1992，they have decreased by 40% and 97% respectively. New HBV infections have significantly decreased，and the prevention and control measures have achieved remarkable economic and social benefits. However，China still confronts numerous challenges in eliminating hepatitis B. The number of chronic HBV carriers remains substantial，and the infection rates among childbearing-age populations and sexually active groups are still relatively high. New infections among adults continue to occur sporadically. Additionally，the vaccination rate for hepatitis B among high-risk adult populations is low，and the newborn immunization program is weak in some areas. The public's awareness of hepatitis B needs to be improved urgently. The rates of detection，diagnosis，and treatment for hepatitis B are relatively low. Moreover，there is currently no effective drug that can completely eliminate HBV. Against the backdrop of rapid advancements in internet and information technologies，as well as in detection and diagnostic methods，China should promptly develop a multi-department prevention and control plan，introduce supportive policies and safeguard measures，and implement a hepatitis B prevention and control strategy that is based on universal immunoprevention and is systematic，comprehensive，standardized，precise，and fully integrated. At the same time，it is essential to improve an information management system，explore the integration of medical care and disease prevention mechanisms，increase financial investment，and implement measures at all stages，including screening，diagnosis，referral，treatment，and care. Additionally，efforts should be made to mobilize the participation of the entire society in order to achieve the goal of eliminating the public health threat of hepatitis B as soon as possible.

Objective:To investigate the prevalence and risk factors of overweight and obesity among Chinese children aged 3-18 years from 11 provinces, antonomous regions, or municipalities.Methods:This national cross-sectional community health survey utilized a multistage stratified cluster-random sampling method to recruit 193 997 nationally representative participants from 11 provinces, autonomous regions, or municipalities between January 2017 and December 2019. All participants underwent physical examinations, and their caregivers completed questionnaires assessing participants′ dietary, lifestyle, familial, and perinatal information. Multilevel multinomial logistic regression models were employed to identify the potential risk factors.Results:The cohort comprised 193 997 children (102 178 boys, 91 819 girls),aged (10±4) years. Overall prevalence rates were 30 574(15.8%)overweight children and 17 217(8.9%) obesity children. Boys exhibited higher overweight and obesity rates than girls (17.0% (17 368/102 178) vs. 14.4% (13 206/102 178), 11.3% (11 553/91 819) vs. 6.2% (5 664/91 819), χ2=249.12,1 578.69,both P<0.001). The detection rates of obesity in Tanner stage 2 and 3 were the highest in boys and girls, with 13.4%(2 231/16 665) and 8.6%(880/10 221) respectively. Risk factors for obesity included parental overweight (paternal OR=2.34 and maternal OR=2.29), annual household income of 100 000-200 000 yuan (compared with<100 000 yuan, OR=1.04), higher paternal education (compared with below high school,high school and a college education OR=1.09,1.14), birth weight >4.0 kg (≤5 and>5 years old OR=1.74, 1.44,respectively), and western food consumption≥1 time/month (compared with<1, 1-2, 3-4,>4 times/month OR=1.36, 1.30, 1.67(≤5 years), 1.19, 1.16, 1.15 (>5 years), respectively) (all P<0.05). Conversely, coarse grain intake≥1 times/week (compared with<1 times/week, every day, 3-4, 1-2 times/week OR=0.74, 0.80, 0.71 (≤5 years), 0.75, 0.87, 0.90(>5 years), respectively, all P<0.05) was associated with reduced obesity risk. Conclusions:Obesity epidemiology in children demonstrates significant heterogeneity across age, gender, geographic regions, and pubertal stages. It is necessary to establish a personalized prevention and control strategy.

Objective To explore the correlation between the expression level of serum fibrinogen-like protein 1(FGL1)and the indexes of metabolism and renal function in patients with diabetic nephropathy(DN)and diabetes mellitus(DM),and provide reference for clinical diagnosis and treatment.Methods From January 2017 to April 2023,30 patients with DM and treated in Jiangsu Province Hospital of Chinese Medicine were selected as the DM group,68 patients with DN were selected as the DN group,and 36 healthy subjects were selected as the control group.The DN group was further divided into the early DN(DN-E)group(n=38)and the late DN(DN-A)group(n=30)according to whether there was a large amount of proteinuria and the severity.Clinical data such as serum albumin(ALB),estimated glomerular filtration rate(eGFR)and albumin-to-creatinine ratio(ACR)were collected.Serum FGL1 level was detected by enzyme-linked immunosorbent assay(ELISA).Pearson linear correlation was used for correlation,the diagnostic value was analyzed by ROC curve.Results Compared with the control group,the levels of ACR,FGL1 in patients with DM group increased,the levels of eGFR decreased,and the differences were statistically significant(t=5.686,4.336,-4.683,all P<0.05).Compated with the DM group,the levels of ACR,FGL1 in patients with DN-E group was increased,and the level of eGFR was decreased,and the differences were statistically significant(t=5.275,3.454,-4.969,all P<0.05).Compared with the DN-E group,the levels of ACR,FGL1 in the DN-A group were increased,the levels of eGFR were decreased,and the differences were statistically significant(t=7.881,7.051,-5.596,all P<0.05).Serum FGL1 level was negatively correlated with ALB and eGFR(r=-0.638,-0.547,all P<0.05),and positively correlated with ACR(r=0.691,P<0.05).The AUC(95%CI),specificity and sensitivity of serum FGL1 level in the diagnosis of DN were 0.947(0.908～0.987),100%and 82.4%,respectively.Conclusion The level of serum FGL1 in DN and DM patients is high,and the level of serum FGL1 is closely related to the common metabolic indexes such as ALB,eGFR and ACR in the diagnosis of DN,which may have certain clinical diagnostic value.

Cardiovascular disease is one of the serious health burdens in the world,and atherosclerosis is its impor-tant pathological basis.In recent years,the effect of environmental pollutants on human health has been paid more and more attention.Some new epidemiological studies and experiments have reported that environmental organic pollutants,involved in the occurrence and development of atherosclerosis,is an independent risk factor of cardiovascular diseases.Evidence shows that it is related to oxidative stress response,cell phenotype transformation,dyslipidemia,genetic changes and so on.This review summarizes available studies on the latest epidemiological studies and experiments of typical per-sistent organic pollutants such as polychlorinated biphenyls and per-and polyfluoroalkyl substances so as to provide refer-ences for future research.

Objective To propose a classification model based on a pseudo-bag strategy and feature adjustment for whole slide imaging in pathology.Methods A pseudo-bag generator was constructed to divide a parent bag into 3 pseudo-bags for increasing the number of training bags.Then,a pseudo-bag learning method based on Nystr?m-based algorithm for approximating self-attention and a selective feature fusion method were employed to process the pseudo-bags.Specifically,the pseudo-bag learning method based on Nystr?m-based algorithm for approximating self-attention reduced computational complexity through an improved multi-head self-attention mechanism while deeply extracting instance features to obtain pseudo-bag classification predictions,thereby enhancing pseudo-bag classification accuracy;and the selective feature fusion method refined pseudo-bag features by filtering and extracting relevant instances.Finally,the model adjusted bag features by extracting confounding factors to avoid interference from irrelevant information and further improve classification accuracy.Results The proposed model was evaluated on two datasets(CAMELYON-16 and TCGA-NSCLC)and compared with 10 other methods,and the results demonstrated that the proposed model achieved the best performance.The proposed method reached an accuracy of 0.943 on the CAMELYON-16 dataset and 0.906 on the TCGA-NSCLC dataset.Conclusion The proposed model can significantly improve the accuracy of whole-slide pathological image classification by effectively mitigating the overfitting and avoiding interference from irrelevant information.