In recent years, the bacteriophage Φ29 (Phi29) DNA polymerase has garnered increasing attention due to its high-fidelity amplification capacity at constant temperatures. To advance the industrial application of this type of isothermal polymerases, this study mined and characterized new enzymes from the microbial metagenome based on the known Phi29 DNA polymerase sequence. The results revealed that a new enzyme, Php29 DNA polymerase, was identified in the microbial metagenome with plants as the hosts. This enzyme exhibited higher strand displacement activity, with a 59.5% similarity to bacteriophage Φ29. Experimental validation demonstrated that the enzyme had 3'→5' exonuclease activity, and its amplification products can serve as substrates for further catalytic reactions. The discovery and validation of Php29 DNA polymerase gives insights into the future industrial application of isothermal polymerases.
DNA-Directed DNA Polymerase/metabolism* ; Bacillus Phages/genetics* ; Metagenome

Bacterial therapy has attracted increasing attention due to its special mechanism and abundant applications. With the flourishing development of synthetic biology, therapeutic genes have been introduced into engineering bacteria to improve their antitumor efficacy. However, it is difficult to spatiotemporally control the expression of these therapeutic genes at the tumor site in vivo, thereby considerably limiting the application of engineered bacteria in tumor treatment. To resolve this problem, we constructed a temperature-responsive bacterial strain capable of triggering the expression of exogenous genes in a laser-controllable way. Noxa, a pro-apoptotic protein, is chosen to test the expression of exogenous protein and its anti-tumor effect in engineered bacteria upon laser irradiation. Firstly, Noxa was fused to the C-terminus of the bacterial outer membrane protein cytolysin A (ClyA), and then the recombinant gene fragment ClyA-Noxa was inserted into the temperature-sensitive plasmid pBV220 and the recombinant plasmid was transformed into non-pathogenic Escherichia coli MG1655. Thus, we constructed the engineering strain (TRB@Noxa) that could express Noxa on the bacterial surface. TRB@Noxa could target and colonize the tumor tissue without causing notable host toxicity. The bacterial infection triggered thrombosis in the tumor tissue, resulting in the darkness of tumor sites. In a xenograft mouse tumor model, our strategy demonstrated precise tumor targeting and strong tumor inhibition. In conclusion, we successfully constructed a new engineering bacterial strain TRB@Noxa. TRB@Noxa combined with photothermal therapy could arrest tumor growth in the absence of photosensitizers, which represents an appealing method for antitumor therapy in the future.
Escherichia coli/radiation effects* ; Animals ; Humans ; Lasers ; Mice ; Proto-Oncogene Proteins c-bcl-2/biosynthesis* ; Neoplasms/therapy* ; Genetic Engineering ; Cell Line, Tumor ; Escherichia coli Proteins/genetics*

Objective:To study and analyze radiation doses to the eye of the lens dose in interventional radiology staff of Guandong medical institutions from 2019 to 2023.Methods:Employing a convenience sampling method, the lens dose and chest dose was monitored with TLD dosimeters in 34 level A tertiary medical institutions. The monitoring data were analyzed on the basis of a summary, and the relationship between the two was explored.Results:A total of 1 033 interventional radiology staff were monitored. The ocular lens doses were in the range of (

Objective:To investigate the inflammatory indicator levels and influencing factors on middle-aged and elderly male residents at different residential distances from a uranium mine in Guangdong, so as to provide scientific data for the health risk assessment of the residents therein.Methods:With stratified sampling method, two groups of the permanent middle-aged and elderly male residents were randomly sampled within < 10 km and 10-20 km of the uranium mine, along with the basic demographic characteristics and lifestyle information collected through face-to-face questionnaire survey. Both height and weight of the respondents were measured using standard method and their body mass indexes (BMI) were calculated. Through collection of the venous blood, the levels of a wide range of inflammatory indicators were measured, such as C-reactive protein (CRP), complement C3, complement C4, leukocytes, lymphocytes, neutrophils, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and others. Multiple linear regression was used to analyze the influencing factors on the levels of inflammation indicators.Results:A total of 867 middle-aged and elderly male residents were included in this study, including one group of 431 residents within the 10-20 km at an average age of 51.54±5.37, and a second group of 436 residents within <10 km at an average age of 52.05±5.24. The result of multiple linear regression showed a positive correlation of the distance groups with complement C4 level ( β=0.014, 95% CI: 0.001-0.027) and lymphocyte number ( β=0.086, 95% CI: 0.003-0.168) ( t=2.07, 2.04, P<0.05). The ages of middle-aged and elderly male residents around the uranium mine was positively correlated ( t=2.50, P<0.05) with the levels of complement C4 ( β=0.018, 95% CI: 0.004-0.031), and negatively correlated ( t=-3.25, -2.97, P<0.05) with the levels of TNF-α ( β=-63.022, 95% CI: -101.114 to -24.929) and IL-6 ( β=-14.694, 95% CI: -24.396 to -4.992). Smoking was positively correlated ( t=4.29, 4.81, 3.19, P<0.05) with leukocytes number ( β=0.630, 95% CI: 0.341-0.918), lymphocytes number ( β=0.226, 95% CI: 0.134-0.319) and neutrophils number ( β=0.372, 95% CI: 0.143-0.601), and negatively correlated ( t=-2.07, -1.98, P<0.05) with the levels of TNF-α ( β=-43.551, 95% CI: -84.778 to -2.324) and IL-6 ( β=-10.603, 95% CI: -21.103 to -0.102). BMI was positively correlated ( t=8.60, 3.62, 3.18, 4.01, 2.10, P<0.05) with complement C3 level ( β=0.108, 95% CI: 0.084-0.133), complement C4 level ( β=0.026, 95% CI: 0.012-0.039), leukocytes number ( β=0.433, 95% CI: 0.166-0.699), lymphocyte number ( β=0.175, 95% CI: 0.089-0.261), and neutrophil number ( β=0.226, 95% CI: 0.014-0.438). Fruit consumption ( β=0.017, 95% CI: 0.001-0.034) was positively correlated with complement C4 levels ( t=2.10, P<0.05). Conclusions:This study showed no significant correlation between the inflammatory index levels of middle-aged and elderly male residents around the uranium mine and uranium mining. Age, smoking, BMI and fruit consumption were the influencing factors on the levels of inflammatory indicators of middle-aged and elderly male residents.

Objective:To investigate differential gene expression, enriched biological processes, and pathway differences between residents of a high-background radiation area (HBRA), Yangjiang, and a control area—Enping.Methods:Seven residents were selected from the HBRA (the HBRA group) and seven from the control area (the control group) using the two-stage random sampling method. The cumulative radiation dose for each individual was calculated based on the ambient gamma exposure levels. Peripheral blood samples were collected and analyzed via high-throughput sequencing to identify differentially expressed genes. Subsequent analyses included gene ontology (GO) for biological process (BP), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and gene set enrichment analysis (GSEA).Results:The median ages of the HBRA and control groups had no statistically significant difference ( P = 0.370). The cumulative external doses for the HBRA and control groups were (99.59±20.07) and (33.82±10.61) mSv, respectively. This difference was statistically significant ( t = -5.88, P = 0.001). High-throughput sequencing identified 1 224 differentially expressed genes in the HBRA group, including 32 senescence-related genes, compared to the control group. The result of GO-BP analysis showed that these genes were predominantly enriched in cell signaling, biosynthesis, localization, cell cycle regulation, and cellular stress responses. KEGG analysis revealed significant enrichment in the chemokine and MAPK signaling pathways, as well as in pathways related to the cell cycle, autophagy, and mitophagy. Furthermore, GSEA analysis confirmed that the differentially expressed genes were mainly related to cell cycle regulation and mitochondrial functions. Conclusions:Differentially expressed mRNAs are found in the peripheral blood of residents in the HBRA. These mRNAs are predominantly associated with key biological processes and pathways, including cell cycle regulation, chemokine and MAPK signaling pathways, and mitophagy.

Vaccination is an effective measure to control infectious diseases and provides lifelong health protection for the public. In recent years, vaccination for adults, especially the elderly, has gradually attracted attention in China, but its vaccination rate is significantly lower than that in some developed countries. To improve adult vaccine coverage, an immunization service model featuring adult vaccine prescriptions has been explored in some provinces of China. This study describes the implementation and characteristics of an adult vaccine prescription pilot program in Shandong Province and discusses considerations related to the concept, compliance, advantages, and difficulties of the vaccine prescription model. Suggestions for developing the vaccine prescription system in China are also provided.

From July 23, 2018, to December 31, 2019, a total of 299 219 children in Shandong Province received the fifth dose of the diphtheria, tetanus, and acellular pertussis combined vaccine (DTaP). Among these recipients, the distribution by age was as follows: 20 children under 2 years old (0.01%), 273 996 children aged 2 years (91.57%), 20 242 children aged 3 years (6.76%), 3 932 children aged 4 years (1.31%), 963 children aged 5 years (0.32%), and 66 children aged 6 years and above (0.02%). In total, 1 972 cases of adverse events following immunization (AEFI) were reported after the administration of the fifth dose of DTaP, resulting in an incidence rate of 659.05 per 100 000 doses. Among these, 1 718 cases were classified as common vaccine reactions, with an incidence rate of 574.16 per 100 000 doses, while 247 cases were identified as rare reactions, yielding an incidence rate of 82.55 per 100 000 doses. The incidence of AEFIs, as well as the rates of common and rare reactions, exhibited a significant increasing trend with the number of doses administered (all P<0.001). Among the rare reactions, there were 10 cases classified as severe, resulting in a reported incidence of 3.34 per 100 000 doses.

Objective To investigate the relationship of triglyceride-glucose(TyG)index and atherogenic index of plasma(AIP)with positive remodeling of coronary arteries in elderly coro-nary heart disease(CHD)patients with concomitant type 2 diabetes mellitus(T2DM).Methods A total of 120 elderly CHD patients with concomitant T2DM admitted to our department from January 2022 to June 2023 were continuously recruited,and according to the remodeling index,they were divided into positive remodeling group(47 cases)and non-positive remodeling group(73 cases).The clinical data were compared between the two groups.Multivariate logistic analysis was used to identify the risk factors for positive remodeling of coronary artery.Spearman correla-tion analysis was employed to analyze the correlation of TyG and AIP with positive remodeling.ROC curve was plotted to analyze the predictive value of TyG and AIP for the remodeling.Results The positive remodeling group had larger ratio of smoking,higher TG and HbA1c levels,and in-creased TyG index and AIP,but lower HDL-C and blood calcium levels than the non-positive re-modeling group(P＜0.05,P＜0.01).Univariate logistic regression analysis showed that smoking,TG,HDL-C,HbA1c,blood calcium,TyG and AIP were risk factors for positive coronary artery remodeling in elderly patients with CHD and T2DM(P＜0.05,P＜0.01).Multivariate logistic re-gression analysis showed that TyG index(OR=7.253,95％CI:2.458-13.364,P=0.035)and AIP(OR=6.017,95％CI:2.205-12.025,P=0.030)were independent risk factors for positive coronary artery remodeling in elderly patients with CHD and T2DM(P＜0.05).The AUC value of TyG index and AIP in predicting positive coronary artery remodeling in elderly CHD patients with T2DM was 0.783 and 0.766,respectively,and the value of their combination in the prediction was 0.868,which was significantly better than the indicator alone(P＜0.05).Conclusion TyG in-dex and AIP are closely associated with positive coronary artery remodeling in elderly CHD pa-tients with T2DM,and can be used as effective indicators in the prediction of positive remodeling,which is of great significance for early clinical identification of high-risk patients and formulation of individual intervention strategies.

To summarize rescuing and nursing experience of 3 ectopic pregnancy patients,suffering from severe toxicity caused by low-dose methotrexate(MTX)treatment.The key points include:constantly monitoring of patients for at least a week after MTX administration,and identifying MTX toxicity related symptoms as soon as possible;promptly establishing a multidisciplinary medical team to establish individualized rescue plans;quickly initiating the rescue therapy and implementing targeted fluid management to accelerate MTX excretion;intensifying protective isolation caring to prevent and control infection;applying refined safety management to prevent spontaneous bleeding;providing intensive caring of skin and mucosal toxicity symptoms to promote healing process;supplying individualized psychological counseling and support in time;strengthening the protection of the damaged organ.After emergent rescuing and intensive nursing,all 3 patients successfully recovered and were discharged from the hospital.

Objective:To investigate the clinical value of 18F-NaF PET/CT coronary plague imaging in evaluating the long-term prognosis of patients with coronary artery disease (CAD). Methods:A retrospective cohort study was conducted among 54 patients (37 males and 17 females, aged (57.2±9.8) years) diagnosed with CAD from a multicenter study between September 2015 and October 2022. All patients underwent 18F-NaF PET/CT and coronary angiography (CAG) within 1 week, and the PET/CT imaging was performed at the First Hospital of Shanxi Medical University. Major adverse cardiovascular events (MACE) were followed up. ROC curves were established to obtain the optimal thresholds of SUV max and accumulated SUV max of all lesions of main coronary artery branches (S-SUV max) for predicting MACE. Cox proportional risk model and Kaplan-Meier method (log-rank test) were used to analyze the predictive value of PET parameters for MACE. Differences in metabolic parameters between 2 groups were compared by Mann-Whitney U test. Results:The median follow-up time of the 54 patients was 6.0(1.8, 6.6) years, and 13(24.1%) patients developed MACE, including 7 deaths, 5 myocardial infarction and 1 severe arrhythmia. S-SUV max in MACE group was significantly higher than that in the non-MACE group (2.64(2.08, 4.49) vs 1.83(0.95, 2.90); Z=-2.04, P=0.041). ROC curve showed that the optimal threshold of S-SUV max for MACE prediction was 2.05 (AUC=0.690). Multivariate Cox analysis showed that S-SUV max was a strong predictor of MACE (hazard ratio ( HR)=2.434(95% CI: 1.547-3.828), P<0.001). ROC curve showed that the optimal threshold of SUV max to predict MACE was 0.55 (AUC=0.659), and univariate Cox analysis showed that SUV max was a factor to predict MACE ( HR=10.192 (95% CI: 2.667-38.953), P=0.001). In 25 patients with incomplete revascularization (ICR), Kaplan-Meier analysis showed that the incidence of MACE in patients with positive 18F-NaF uptake (single medium stenosis (40%-70%) with SUV max≥0.55) was significantly higher than that in patients with negative 18F-NaF uptake (5/14 vs 0/11; χ2=6.07, P=0.014). Conclusions:18F-NaF PET/CT can be used as an independent predictor of MACE in patients with CAD and can quantitatively assess the long-term progression of moderate coronary artery stenosis. In the future, it is expected to be a new non-invasive way to guide the revascularization treatment decision of multi-vessel CAD.