The engineering application of microbially induced carbonate precipitation(MICP)is limited by pH-dependent conformational dynamics of urease.Focusing on the α-subunit urease from Sporosarcina pasteurii,this study integrated conductivity experiments and constant-pH molecular dynamics simulations to analyze active site conformational dynamics and catalytic function across pH 3-11.Results showed that under neutral conditions(pH 7-8),key histidine residues(HIS139/HIS249)exhibited minimal dis-placement(＜0.5 ?),the longest hydrogen bond lifetime(＞8 ps),highest conformational stability(root mean square deviation,RMSD:0.15-0.18 nm),and optimal catalytic activity(conductivity change rate:0.03 mS/cm·min-1,CaCO3 precipitation:3.84 g).Extreme pH(pH 3/11)induced structural collapse(displacement up to 1.8 ?)and complete activity loss.Simulations revealed that neutral pH sta-bilizes a protonation-dependent cooperative allosteric network by maintaining active site cavity volume(～120 ?3)and moderate conformational coherence(correlation coefficient～0.8).This work deciphers the molecular mechanism of pH-regulated urease dynamics through protonation states,providing theoreti-cal support for MICP applications in acidic mine tailing remediation and alkaline soil stabilization.

Vertebral refracture following percutaneous vertebral augmentation (PVA) is commonly seen in elderly patients with osteoporotic thoracolumbar compression fractures (OTLCF). It can lead to recurrent pain, loss of vertebral height, progression of kyphosis, and even neurological dysfunction, significantly impairing patients′ quality of life. Current diagnosis and treatment face multiple challenges, including high misdiagnosis rate, difficulty in choosing between surgical and non-surgical treatment options, lack of standardized surgical protocols, interference from intralesional bone cement during procedures, inadequate stability of internal fixation in osteoporotic bone, and suboptimal compliance of anti-osteoporotic therapy. Establishing a standardized diagnostic and therapeutic framework is urgently needed. To standardize the management process and improve outcomes for vertebral refractures after PVA in elderly OTLCF patients, Spinal Trauma Group of the Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field to develop Guideline for the diagnosis and treatment of vertebral refracture after percutaneous vertebral augmentation in elderly patients with osteoporotic thoracolumbar compression fractures ( version 2025), based on current literature and clinical experience, and adhering to principles of scientific rigor and clinical applicability. A total of 11 recommendations were proposed, encompassing diagnosis, treatment, and rehabilitation of vertebral refracture after PVA in elderly patients with OTLCF, aiming to provide a foundation for a standardized management.

The engineering application of microbially induced carbonate precipitation(MICP)is limited by pH-dependent conformational dynamics of urease.Focusing on the α-subunit urease from Sporosarcina pasteurii,this study integrated conductivity experiments and constant-pH molecular dynamics simulations to analyze active site conformational dynamics and catalytic function across pH 3-11.Results showed that under neutral conditions(pH 7-8),key histidine residues(HIS139/HIS249)exhibited minimal dis-placement(＜0.5 ?),the longest hydrogen bond lifetime(＞8 ps),highest conformational stability(root mean square deviation,RMSD:0.15-0.18 nm),and optimal catalytic activity(conductivity change rate:0.03 mS/cm·min-1,CaCO3 precipitation:3.84 g).Extreme pH(pH 3/11)induced structural collapse(displacement up to 1.8 ?)and complete activity loss.Simulations revealed that neutral pH sta-bilizes a protonation-dependent cooperative allosteric network by maintaining active site cavity volume(～120 ?3)and moderate conformational coherence(correlation coefficient～0.8).This work deciphers the molecular mechanism of pH-regulated urease dynamics through protonation states,providing theoreti-cal support for MICP applications in acidic mine tailing remediation and alkaline soil stabilization.

Vertebral refracture following percutaneous vertebral augmentation (PVA) is commonly seen in elderly patients with osteoporotic thoracolumbar compression fractures (OTLCF). It can lead to recurrent pain, loss of vertebral height, progression of kyphosis, and even neurological dysfunction, significantly impairing patients′ quality of life. Current diagnosis and treatment face multiple challenges, including high misdiagnosis rate, difficulty in choosing between surgical and non-surgical treatment options, lack of standardized surgical protocols, interference from intralesional bone cement during procedures, inadequate stability of internal fixation in osteoporotic bone, and suboptimal compliance of anti-osteoporotic therapy. Establishing a standardized diagnostic and therapeutic framework is urgently needed. To standardize the management process and improve outcomes for vertebral refractures after PVA in elderly OTLCF patients, Spinal Trauma Group of the Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field to develop Guideline for the diagnosis and treatment of vertebral refracture after percutaneous vertebral augmentation in elderly patients with osteoporotic thoracolumbar compression fractures ( version 2025), based on current literature and clinical experience, and adhering to principles of scientific rigor and clinical applicability. A total of 11 recommendations were proposed, encompassing diagnosis, treatment, and rehabilitation of vertebral refracture after PVA in elderly patients with OTLCF, aiming to provide a foundation for a standardized management.

Objective:To explore whether multi-parametric MRI (mpMRI) combined with 68Ga-prostate specific membrane antigen (PSMA) PET/CT can improve the detection efficiency of clinically significant prostate cancer (csPCa). Methods:Clinical and imaging data of 152 patients (age (68.5±8.5) years) who underwent mpMRI and 68Ga-PSMA PET/CT examination for suspected prostate cancer in the First Affiliated Hospital of the Air Force Medical University from January 2021 to November 2022 were retrospectively analyzed, with the histopathological results from transrectal ultrasound guided biopsy as reference. Lesions with Gleason scores (GS) ≥3+ 4 from the biopsy were diagnosed with csPCa, and lesions with negative biopsy or GS 6 were diagnosed with non-csPCa. MpMRI was evaluated independently by two radiologists according to the Prostate Imaging Reporting and Data System (PI-RADS) version 2.1. The radioactive uptake of 68Ga-PSMA PET/CT in prostate lesions was evaluated by SUV max. The independent-sample t test, Mann-Whitney U test and χ2 test were used to compare differences between the two groups, and then multivariate logistic regression analysis was performed. ROC curves analysis was used to analyze the diagnostic efficacies of individual and combined factors and Delong test was used. Results:There were 85 csPCa and 67 non-csPCa confirmed. Prostate specific antigen (PSA), PI-RADS score and SUV max were significantly different between the csPCa group and the non-csPCa group ( χ2=68.06, U values: -7.66, -8.98, all P<0.001). Multivariate logistic regression analysis indicated that PI-RADS score (odds ratio ( OR)=3.424, 95% CI: 1.651-7.100) and SUV max ( OR=1.931, 95% CI: 1.403-2.658) were independent predictors of csPCa (both P<0.001). ROC curves analysis revealed that the cut-off value for diagnosing csPCa was 4 for PI-RADS score and 5.6 for SUV max. The accuracy of mpMRI and PET/CT alone in csPCa diagnosis was 80%(122/152) (AUC of 0.789(95% CI: 0.711-0.866) with the sensitivity and specificity of 91%(77/85) and 67%(45/67)), and 87%(132/152) (AUC of 0.876(95% CI: 0.817-0.936) with the sensitivity and specificity of 81%(69/85) and 94%(63/67)), respectively. Several joint models incorporating 68Ga-PSMA PET/CT with mpMRI data were investigated, the model of PI-RADS 5 or PI-RADS 3-4 and SUV max>5.6 showed better performance than mpMRI and PET/CT alone and other joint models ( z values: 2.01-3.64, all P<0.05), with the accuracy of 91%(138/152) (AUC of 0.910(95% CI: 0.857-0.962) with the sensitivity and specificity of 89%(76/85) and 93%(62/67)). Conclusion:MpMRI combined with 68Ga-PSMA PET/CT can significantly improve the detection efficiency of csPCa, with the principal effect being improved in risk stratification of PI-RADS 3-4 lesions in mpMRI.

Heme oxygenase-1(HO-1)is an inducible heme oxygenase and a catalytic enzyme for heme decomposition reactions,which can catalyze the heme decomposition into CO,biliverdin and Fe2+.HO-1 and its metabolites have anti-inflammatory,antioxidant and anti-apoptotic effects in human body,and play an important role in neurodegenerative diseases such as Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,and Huntington's disease.This article will review the production,distribution,and gene structure of HO-1,the biological characteristics of its metabolites,and the role and mechanism of HO-1 in neurodegenerative diseases,in order to provide a theoretical basis for the clinical application of HO-1.

This work was aimed at predicting and verifying B-cell epitopes of SARS-CoV-2 E protein through bioinformatics methods,and clarifying the dominant B cell epitopes with mouse polyclonal antibody serum prepared through SARS-CoV-2 re-combinant E protein immunization and human positive serum vaccinated with inactivated SARS-CoV-2 vaccine.The structural and B-cell linear epitopes of SARS-CoV-2 E protein were predicted with SOPMA,Expasy,SWISS-MODEL,IEDB database,and Bepid-2.0 software.Candidate epitopes were expressed as GST-tagged recombinant protein fragments in an E.coli sys-tem,and their immunoreactivity with mouse and human poly-clonal positive serum against SARS-CoV-2 E protein was de-tected by western blotting and indirect ELISA,respectively.The epitope prediction results showed that E protein contained linear B cell epitopes Ser6-Val14 and Tyr57-Pro71,and the conformational epitopes of Glu8-Val12,Leu39-Tyr59,and Ser60-Leu65.The GST tagged recombinant E protein fragments of E1 and E3,containing Ser6-Val14 and Tyr57-Pro71 epitopes,respectively,as well as E2 without an epitope sequence as a control,were expressed in an E.coli expression system and successfully purified with an Ni-NTA column.Western blotting and indirect ELISA analysis indicated that all mouse and human SARS-CoV-2 positive sera positively reacted with only E1 and E3 proteins,but negatively reacted with E2 protein,thus indicating that the corresponding epitope prediction with Ser6-Val14 and Tyr57-Pro71 was correct.This study successfully predicted and preliminarily identified two linear B cell epitopes of SARS-CoV-2 E protein,thus providing a reference for the preparation of new coronavirus vaccines and the analysis of immune response characteristics.

The AP2/ERF gene family is one of the largest transcription factor families in the plant kingdom, and plays an important role in response to biological and abiotic stresses, plant hormone responses, and plant growth and development. In this study, the AP2/ERF family of Panax notoginseng was identified by bioinformatics methods, and the physicochemical properties, structure, phylogenetic relationship, expression pattern and function of PnDREB4 gene of the family were analyzed. The results showed that 140 AP2/ERF family members were identified in P. notoginseng, which were divided into DREB, ERF, AP2, RAV and Sololit subgroups. The physicochemical properties and motifs of proteins were similar among the subgroups. There were 34 differentially expressed genes in the AP2/ERF family of Fusarium oxysporum infected P. notoginseng plants, and 19 genes were up-regulated. The expression level of PnDREB84 was up-regulated with the extension of Fusarium oxysporum infection time in the range of 0-96 h. The content of ABA and SA in P. notoginseng plants overexpressing PnDREB84 gene increased after 4 ℃ stress. The results showed that PnDREB84 gene plays a dual regulatory role in the process of biological stress and abiotic stress. PnDREB84 gene can be used as a potential molecular marker for the breeding of new varieties of P. notoginseng. The identification of AP2/ERF transcription factor and function analysis of PnDREB84 gene of P. notoginseng provided data support for the analysis of stress resistance mechanism of P. notoginseng and the breeding of new varieties.

Objectives: To investigate the clinical application effect of a quantitative method of atlantoaxial reduction angle in basilar invagination. Methods: A retrospective analysis of clinical and radiographic data was conducted of 38 patients with complicated atlantoaxial dislocation and basilar invagination admitted to the Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University from May 2020 to May 2022. There were 5 males and 33 females, aged (53.5±9.9) years (range: 38 to 80 years). All patients underwent C_1-2 interarticular fusion cage implantation+occipital-cervical fixation by pressing rob with the cantilever technique. The atlantoaxial reduction model of previous studies by our team was used to calculate the reduction angles before surgery. Then titanium rods of prebending angle were prepared according to the calculation before the operation. After that quantitative reduction of angle was performed during the operation. The paired t-test was used to compare the difference between the theoretical and actual reset value. Results: The theoretical reduction angle of all patients was (10.62±1.78)° (range: 6.40° to 13.20°), the actual reduction angle was (10.53±1.63)° (range: 6.70° to 13.30°) and there was no statistical difference between them (t=1.688, P=0.100). The theoretical posterior occipitocervical angle after the operation of all patients was (117.37±5.88)° (range: 107.00° to 133.00°), the actual posterior occipitocervical angle after the operation was (118.25±6.77)° (range: 105.40° to 135.80°) and there was no statistical difference between them (t=-0.737, P=0.466). The postoperative follow-up time of the patients was more than 6 months and the symptoms of all patients were relieved. All patients had satisfactory fusion between small joints without incision infection, internal fixation fracture, displacement, atlantoaxial redislocation, and other long-term complications. Conclusion: The quantitative method of atlantoaxial reduction angle in basilar invagination can calculate the theoretical reduction angle of the clivus axis angle and guide the preparation of the pre-bending titanium rod before surgery, so as to realize the quantification of the atlantoaxial reduction angle.

In August 2021, three students with diarrhea from the same school visited a local hospital in the S district of Beijing. An epidemic investigation showed that there were more students with diarrhea in the same school and they had one meal together. Campylobacter jejuni was isolated from both patients with diarrhea and asymptomatic food handlers; however, the latter also carried Campylobacter coli. Phylogenomic analysis showed that there was a campylobacteriosis outbreak among the students, and the asymptomatic food handler may have been the source of the infection. Routine inspection and surveillance for Campylobacter is needed for the food producing staff, particularly those cooking in the cafeteria in schools or other public food services.
Humans ; Campylobacter Infections/epidemiology* ; Gastroenteritis ; Diarrhea ; Campylobacter ; Disease Outbreaks