O-acetyl-L-homoserine (OAH) is a promising platform compound for the production of L-methionine and other valuable compounds, while its low yield and low conversion rate limit the industrial application. To solve these problems, we constructed a strain for high OAH production with the previously constructed L-homoserine producer Escherichia coli HS33 as the chassis by systematic metabolic engineering. Firstly, PEP accumulation, pyruvate utilization, and OAH synthesis pathway (overexpressing aspB, aspA, and thrA^C1034T) were enhanced to obtain an initial strain accumulating 13.37 g/L OAH. Subsequently, the co-factor synthesis genes were integrated to supply reducing power and energy, which increased the yield to 15.79 g/L. The OAH yield of the engineered strain OAH28 was further increased to 17.49 g/L by strengthening the acetic acid reuse pathway, improving the supply of acetyl-CoA, and regulating the expression of MetX from different sources. Finally, in a 5 L fermenter, OAH28 achieved an OAH titer of 47.12 g/L, with a glucose conversion rate of 32% and productivity of 0.59 g/(L·h). The results lay a foundation for increasing the OAH production by metabolic engineering and give insights into the industrial production of OAH.
Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Homoserine/biosynthesis* ; Fermentation

Concrete is widely used in building construction, civil engineering, roads, bridges, etc., but concrete cracking remains a major issue in the engineering industry. To develop an effective and feasible concrete repair technology, this study combined microbial and microencapsulation technologies to prepare a multi-layer compound microcapsule using the piercing method. The formulation and drying method of microcapsules were optimized by taking their embedding rate and mechanical properties as evaluation criteria. The calcium transcrystallization process of microcapsules and the crystal form of products were characterized and compared with the calcium transcrystallization process in free cells. Finally, the effects of microcapsule incorporation on mechanical properties, impermeability, and self-healing performance of concrete specimens were then tested. The results showed that the air-dried multi-layer compound microcapsules, formulated with 1.0% wet cells of Bacillus cereus, 1.5% calcium chloride, 3.0% sodium alginate, 5.0% nutrients, 6.0% glycerol, 0.6% chitosan, and 2.0% urea, achieved an embedding rate of 95.3%, a rupture force of 60.0 N and a hardness of 150.8 N. These microcapsules can transform from a solid state to a flowing colloidal state when the microorganisms inside undergo a calcium formation reaction. Both the microcapsules and free cells produced stable calcite crystal forms of calcium carbonate through the calcium conversion reaction, with the microcapsules producing more uniform-sized particles, which are more conducive to accumulation in cracks, thereby enhancing the stability of repair. When microcapsules were incorporated into the concrete specimen at a content of 0.45%, the flexural strength of the specimen increased by 17.3%, and the compressive strength increased by 12.3%. In the water impermeability test, specimens with microcapsules demonstrated better impermeability compensation for the cement concrete than those with free cells. The self-healing effect of cracks proved that multi-layer compound microcapsules could completely repair cracks up to 0.7 mm wide, and a repair rate of 95% for 0.8 mm wide cracks. In this study, a multi-layer compound microcapsule was developed to protect microorganisms in concrete and provide nutrients required for their growth, which provided a new idea for microbial induced calcium carbonate precipitation in concrete crack repair.
Construction Materials ; Capsules/chemistry* ; Bacillus cereus/metabolism* ; Alginates/chemistry*

OBJECTIVE: To explore decompression strategies for lateral lumbar spinal stenosis under unilateral biportal endoscopy (UBE) assistance. METHODS: A clinical data of 86 patients with lateral lumbar stenosis treated with UBE-assisted intervertebral decompression between September 2022 and December 2023 was retrospectively analyzed. There were 42 males and 44 females with an average age of 63.6 years (range, 45-79 years). The disease duration ranged from 6 to 14 months (mean, 8.5 months). Surgical levels included L _{2, 3} in 3 cases, L _{3, 4} in 26 cases, L _{4, 5} in 42 cases, and L ₅, S ₁ in 15 cases. According to Lee's grading system, there were 21 cases of grade 1, 37 cases of grade 2, and 28 cases of grade 3 for lumbar spinal stenosis. Based on the location of stenosis and clinical symptoms, the 33 cases underwent interlaminar approach, 7 cases underwent interlaminar approach with auxiliary third incision, 26 cases underwent contralateral inclinatory approach, and 20 cases underwent paraspinal approach; then, the corresponding decompression procedures were performed. Visual analogue scale (VAS) score was used to evaluate lower back/leg pain before operation and at 1 and 3 months after operation, while Oswestry disability index (ODI) was used to evaluate spinal function. At 3 months after operation, the effectiveness was evaluated using the modified MacNab evaluation criteria. The spinal stenosis and decompression were evaluated based on Lee's grading system using lumbar MRI before operation and at 3 months after operation. RESULTS: All procedures were successfully completed with mean operation time of 95.1 minutes (range, 57-166 minutes). Dural tears occurred in 2 cases treated with interlaminar approach with auxiliary third incision. All incisions healed by first intention. All patients were followed up 3-10 months (mean, 5.9 months). The clinical symptoms of the patients relieved to varying degrees. The VAS scores and ODI of lower back and leg pain at 1 and 3 months after operation significantly improved compared to preoperative levels ( P<0.05), and the indicators at 3 months significantly improved than that at 1 month ( P<0.05). According to the modified MacNab evaluation criteria, the effectiveness at 3 months after operation was rated as excellent in 52 cases, good in 21 cases, and poor in 13 cases, with an excellent and good rate of 84.9%. No lumbar instability was detected on flexion-extension X-ray films during follow-up. The Lee's grading of lateral lumbar stenosis at 2 days after operation showed significant improvement compared to preoperative grading ( P<0.05). CONCLUSION For lateral lumbar spinal stenosis, UBE-assisted decompression of the spinal canal requires the selection of interlaminar approach, interlaminar approach with auxiliary third incision, contralateral inclinatory approach, and paraspinal approach based on preoperative imaging findings and clinical symptoms to achieve better effectiveness.
Humans ; Spinal Stenosis/diagnostic imaging* ; Female ; Male ; Middle Aged ; Decompression, Surgical/methods* ; Aged ; Lumbar Vertebrae/surgery* ; Endoscopy/methods* ; Retrospective Studies ; Treatment Outcome

Objective To analyze the urban drinking water quality and its influencing factors in Anhui Province from 2014 to 2022, and to provide a scientific basis for water quality improvement and protection. Methods The data were collected, saved and monitored according to the Standard Test Method for Drinking Water (GB/T5750-2006) and evaluated according to the Hygienic Standard for Drinking Water (GB 5749-2006). Results A total of 20 941 samples were collected, and the overall qualified rate was 84.26%. The qualified rate of urban drinking water increased from 76.9% in 2014 to 93.3% in 2022, and the qualified rate of water quality was on the rise (χ²=544.43, P＜0.01). From 2014 to 2022, the qualified rate of water quality in dry season was higher than that in wet season (χ²=35.98, P<0.001), the qualified rate of surface water was higher than that of ground water (χ²=4440.8, P<0.001), and the qualified rate of peripheral tap water was higher than that of factory water (χ²=145.1, P<0.001). Among all kinds of disinfection methods, chlorination disinfection had the highest qualified rate (χ²=1483.8, P<0.001). The qualified rate of water quality increased with the increase of the scale of water plant. Among the inspected indicators, the main unqualified indicators were chlorine dioxide (7.72%), fluoride (7.41%), free residual chlorine (3.90%), and total bacterial count (2.13%). Conclusion The passing rate of urban drinking water quality in Anhui Province is on an upward trend, and the quality of urban drinking water has improved. However, it is still important to pay attention to the problem of excessive microorganism and fluoride in water, and the quality of drinking water varies from place to place.

Intraoperative cell salvage (IOCS) has been widely applied as an important blood conservation measure in surgical operations. However, there is currently a lack of clinical practice guidelines for the implementation of IOCS in patients with malignant tumors. This report aims to provide clinicians with recommendations on the use of IOCS in patients with malignant tumors based on the review and assessment of the existed evidence. Data were derived from databases such as PubMed, Embase, the Cochrane Library and Wanfang. The guideline development team formulated recommendations based on the quality of evidence, balance of benefits and harms, patient preferences, and health economic assessments. This study constructed seven major clinical questions. The main conclusions of this guideline are as follows: 1) Compared with no perioperative allogeneic blood transfusion (NPABT), perioperative allogeneic blood transfusion (PABT) leads to a more unfavorable prognosis in cancer patients (Recommended); 2) Compared with the transfusion of allogeneic blood or no transfusion, IOCS does not lead to a more unfavorable prognosis in cancer patients (Recommended); 3) The implementation of IOCS in cancer patients is economically feasible (Recommended); 4) Leukocyte depletion filters (LDF) should be used when implementing IOCS in cancer patients (Strongly Recommended); 5) Irradiation treatment of autologous blood to be reinfused can be used when implementing IOCS in cancer patients (Recommended); 6) A careful assessment of the condition of cancer patients (meeting indications and excluding contraindications) should be conducted before implementing IOCS (Strongly Recommended); 7) Informed consent from cancer patients should be obtained when implementing IOCS, with a thorough pre-assessment of the patient's condition and the likelihood of blood loss, adherence to standardized internally audited management procedures, meeting corresponding conditions, and obtaining corresponding qualifications (Recommended). In brief, current evidence indicates that IOCS can be implemented for some malignant tumor patients who need allogeneic blood transfusion after physician full evaluation, and LDF or irradiation should be used during the implementation process.

Glioblastoma(GBM)is the most aggressive primary malignant tumor in the central nervous system.GBM frequently recurs after surgery and has limited therapeutic options.Hydrogels,characterized by their injectability,biocompatibility,and controlled drug release,of-fer innovative solutions for postoperative GBM management.Advances in hydrogel technology provide new avenues for personalized GBM treatments with significant clinical potential.This article focuses on the current progress in the research on hydrogels as carriers for chemo-therapeutic drugs,immunomodulatory platforms,and multimodal therapeutic systems.Key strategies,including thermo-and pH-responsive gels,co-delivery systems,and the regulation of macrophage function,are analyzed for their therapeutic efficacy.Additionally,the advant-ages of hydrogels in surgical cavity filling,targeted therapy,and recurrence prevention are highlighted.We also discuss the challenges in clin-ical translation and future directions of hydrogel application in postoperative GBM management.

Objective:To understand the current status and characteristics of clinical trials for oral diseases in China, for the purpose of providing a reference for the research and development of oral diseases in China.Methods:Retrieving the information on clinical trials related to oral diseases registered on the "Platforms for drug clinical trial registration and information" of the National Medical Products Administration from the date of the database establishment to December 31, 2024. The number of clinical trials, type of drugs, trial phases, indication, trial scope, design types were statistically analyzed.Results:As of December 31, 2024, a total of 578 drug clinical trials for oral disease were registered, accounting for 2.1% (578/27 905) of the clinical trials disclosed on the platform during the same period. Bioequivalence clinical trials accounted for the highest proportion [73.9% (427/578)], followed by Phase Ⅰ [9.0% (52/578)], Phase Ⅱ [8.0% (46/578)], and Phase Ⅲ [4.5% (26/578)]. The 578 clinical trials involved 149 types of trial drugs, mainly chemical drugs, among which 127 were developed by domestic pharmaceutical enterprises and 27 by international pharmaceutical enterprises (the five investigational drugs have undergone clinical trials by both domestic and international pharmaceutical companies). The project leader units of the 578 drug clinical trials were distributed in 27 provinces, autonomous regions, municipalities, and Hong Kong Special Administrative Region. Excluding 427 bioequivalence clinical trials, the project leader units of 151 new drug clinical trials showed a significant aggregation phenomenon, and only three specialized oral hospitals have served as project leader units for drug clinical trials.Conclusions:The number of drug clinical trials for oral disease in China has generally shown an increasing trend, but there are still problems such as small number of clinical trials, low proportion of investment in new drug development and international multicenter trials, concentrated indications of clinical trials and insufficient clinical trial experience in specialized oral medical institutions. Enhancing the enthusiasm and innovation capabilities of domestic pharmaceutical enterprises in the research and development of oral diseases drugs, exploring the advantages of traditional Chinese medicine/natural medicine resources for oral diseases, and establishing a clinical research system in specialized oral medical institutions are of great significance for the development of oral drugs.

Objective:To investigate the role of YTHDF2 in cervical lesions and its potential molecular mechanism.Methods:Gene expression data of cervical tissue were obtained from the GEO database to analyze the expression of YTHDF2 mRNA and perform pathway enrichment analysis. Patients with cervical lesions diagnosed by thinprep cytologic test in Gynecological Outpatient Department of Maternal and Child Health Hospital in Jiexiu, Shanxi Province, were selected as the research subjects. Data of cervical lesions and cervical exfoliated cells were collected. HPV infection status was detected by flow-through hybridization, and the expression of YTHDF2 mRNA was detected by reverse transcription real-time polymerase chain reaction. The expression of YTHDF2 in cervical lesions and the mediating role of HPV infection in the relationship between YTHDF2 and squamous intraepithelial lesion (SIL) were evaluated. YTHDF2-related genes were screened from multiple datasets in the GEO and ENCORI databases, and their expression, immune infiltration, and survival analysis were performed to assess the association between YTHDF2 and prognosis. Results:Compared with normal cervical tissue, YTHDF2 was highly expressed in cervical lesion tissue ( P<0.05). A total of 3 672 differentially expressed genes were screened from the dataset GSE49339. Gene Ontology analysis showed that YTHDF2 was mainly involved in transcription regulation. Kyoto Encyclopedia of Genes and Genomes analysis showed that YTHDF2 might be related to HPV infection and other signaling pathways. In the mediation analysis, χ2 test results showed that the expression level of YTHDF2 was significantly different among groups ( χ2=22.47, P<0.001). Trend χ2 test further showed that the expression level of YTHDF2 was upregulated with the degree of cervical precancerous lesions (trend χ2=10.26, P=0.001). Multivariate logistic regression analysis indicated that high YTHDF2 expression increased the risk of low-grade squamous intraepithelial lesions ( OR=3.15, 95% CI: 1.93-5.15) and high-grade squamous intraepithelial lesions ( OR=1.85, 95% CI: 1.01-3.39). Mediation effect analysis revealed a partial mediating effect of HPV infection between YTHDF2 and SIL, accounting for 32.02% of the total effect. Twelve YTHDF2 related genes were screened by the intersection of multiple datasets. The immune infiltration analysis results showed that YTHDF2 and related genes KLF4, E2F3 and HOXC6 were associated with immune infiltration (all P<0.05). Multivariate Cox proportional hazard regression model analysis showed that low expression of KLF4 ( HR=0.53, 95% CI: 0.30-0.94) and high expression of RHOB ( HR=1.80, 95% CI: 1.04-3.13) were risk factors for the prognosis of cervical cancer. Conclusion:YTHDF2 is highly expressed in cervical lesions and may have been involved in the regulation of HPV infection-related pathways and its downstream related genes are related to immune infiltration and prognosis of cervical cancer, providing a theoretical basis for the study of mechanisms related to cervical lesions.

Objective To quantitatively evaluate the structure and content of the long-term care insurance(LTCI)policy in China's deeply aging areas.Methods Using the Policy Modeling Consistency(PMC)index model indicator design method,a LTCI policy evalua-tion index system was constructed,consisting of nine primary indicators and 34 secondary indicators.A total of 123 provincial-level LTCI policies issued in deeply aging regions of China between June 1,2014,and October 1,2024 were analyzed.High-frequency word extraction was performed using ROSTCM 6.0,and a social network diagram of LTCI policies was created.The policy structure and content were quantitatively evaluated and ana-lyzed based on the established policy evaluation index system.Results The main content of LTCI policies in deeply aging areas of China covered services,institutions and assessment.The highest policy score was 7.28,and the lowest was 2.20,with an average score of 5.00.There were 25 perfect policies,63 excellent policies,28 good policies and seven qualified policies.In the dimension of policy content,the indexes of five primary indicators of policy evaluation,policy target groups,policy nature,policy perspective and policy tools were 0.60 or more;while the indexes of four primary indicators of policy content,incentives and constraints,policy timeliness,and policy level were 0.50 or less.Conclusion LTCI policies issued in China's deeply aging areas provide comprehensive coverage in aspects such as poli-cy evaluation,policy target groups and policy nature,and need to be improved in policy tool selection and the construction of incentive and constraint mechanisms.