Over the past three decades， China has made significant progress in the prevention and control of viral hepatitis， and the incidence rates of new-onset pediatric hepatitis B virus infections and acute viral hepatitis in the population have reduced to a relatively low level； however， there is still a heavy disease burden of chronic viral hepatitis in China， which severely affects the health status of the population. This study systematically summarizes the achievements of viral hepatitis prevention and control in China， analyzes existing problems and challenges， and proposes comprehensive prevention and control strategies and measures to eliminate viral hepatitis as a public health threat based on the national conditions of China， in order to provide a reference for related departments in China on how to achieve the action targets for eliminating viral hepatitis as a public health threat by 2030.

ObjectiveThe rapid advancement of bioanalytical technologies has heightened the demand for high-throughput, label-free, and real-time cellular analysis. Electrochemical impedance spectroscopy (EIS) operating in the GHz frequency range (GHz-EIS) has emerged as a promising tool for characterizing cell suspensions due to its ability to rapidly and non-invasively capture the dielectric properties of cells and their microenvironment. Although GHz-EIS enables rapid and label-free detection of cell suspensions, significant challenges remain in interpreting GHz impedance data for complex samples, limiting the broader application of this technique in cellular research. To address these challenges, this study presents a novel method that integrates GHz-EIS with deep learning algorithms, aiming to improve the precision of cell suspension concentration identification and quantification. This method provides a more efficient and accurate solution for the analysis of GHz impedance data. MethodsThe proposed method comprises two key components: dielectric property dataset construction and backpropagation (BP) neural network modeling. Yeast cell suspensions at varying concentrations were prepared and separately introduced into a coaxial sensor for impedance measurement. The dielectric properties of these suspensions were extracted using a GHz-EIS dielectric property extraction method applied to the measured impedance data. A dielectric properties dataset incorporating concentration labels was subsequently established and divided into training and testing subsets. A BP neural network model employing specific activation functions (ReLU and Leaky ReLU) was then designed. The model was trained and tested using the constructed dataset, and optimal model parameters were obtained through this process. This BP neural network enables automated extraction and analytical processing of dielectric properties, facilitating precise recognition of cell suspension concentrations through data-driven training. ResultsThrough comparative analysis with conventional centrifugal methods, the recognized concentration values of cell suspensions showed high consistency, with relative errors consistently below 5%. Notably, high-concentration samples exhibited even smaller deviations, further validating the precision and reliability of the proposed methodology. To benchmark the recognition performance against different algorithms, two typical approaches—support vector machines (SVM) and K-nearest neighbor (KNN)—were selected for comparison. The proposed method demonstrated superior performance in quantifying cell concentrations. Specifically, the BP neural network achieved a mean absolute percentage error (MAPE) of 2.06% and an R² value of 0.997 across the entire concentration range, demonstrating both high predictive accuracy and excellent model fit. ConclusionThis study demonstrates that the proposed method enables accurate and rapid determination of unknown sample concentrations. By combining GHz-EIS with BP neural network algorithms, efficient identification of cell concentrations is achieved, laying the foundation for the development of a convenient online cell analysis platform and showing significant application prospects. Compared to typical recognition approaches, the proposed method exhibits superior capabilities in recognizing cell suspension concentrations. Furthermore, this methodology not only accelerates research in cell biology and precision medicine but also paves the way for future EIS biosensors capable of intelligent, adaptive analysis in dynamic biological research.

An intensive breast array sensor was designed based on three-dimensional electrical impedance tomography in this work.Firstly,an electrical impedance sensor for detection of breast cancer was developed.The sensor adopted the integrated design of excitation electrode array and ground electrode to achieve structural simplification.It realized electric field densification through conical matrix and double-layer circumferentially arranged electrode array and improved the detection accuracy of target object through taper optimization.Secondly,the imaging system was designed,and the sensor was optimized by numerical simulation.The simulation results showed that halving the number of electrodes did not affect imaging accuracy of the sensor,but could improve the imaging speed.Finally,the performance of the sensor was verified by experiment.The signal-to-noise ratio and channel consistency of the system were at a good level.The sensor was used to reconstruct three-dimensional image of the experimental model with relative volume of the detection field of 0.4%.The image correlation coefficient of the single target imaging was above 0.6 and the position of the double target object could be clearly identified,and thus the visual detection of breast cancer was realized.

Objective To explore the correlations between image quality of prospective and retrospective electrocardiogram(ECG)-gated CT coronary angiogram and radiation dose in patients with different heart rates.Methods A total of 135 patients undergoing 256-slice spiral CT coronary angiography were enrolled in the study.Among them,66 cases received prospective ECG-gated scanning(prospective ECG-gated group)and further divided into two subgroups with heart rate≤80 beats/min(prospective ECG-gated+low heart rate subgroup,n=39)and>80 beats/min(prospective ECG-gated+high heart rate subgroup,n=27).The other 69 cases underwent retrospective ECG-gated scanning(retrospective ECG-gated group),including 45 cases with heart rate≤80 beats/min(retrospective ECG-gated+low heart rate subgroup)and 24 with heart rate>80 beats/min(retrospective ECG-gated+high heart rate subgroup).The baseline data,image quality[mean CT value,image noise,signal-to-noise ratio(SNR),subjective image quality score]and radiation dos[CT volume dose index(CTDIvol),dose length product(DLP),effective dose(ED)]were compared among 4 subgroups.The correlations of image quality with heart rate and radiation dose in prospective and retrospective ECG-gated groups were analyzed.Results The heart rates in prospective and retrospective ECG-gated+low heart rate subgroups were lower than those in prospective and retrospective ECG-gated+high heart rate subgroups(P<0.05).When comparing the mean CT value,image noise,SNR and subjective image quality score among 4 subgroups,no statistically significant differences were observed(P>0.05).The CTDIvol,DLP and ED in prospective ECG-gated+low heart rate subgroup were significantly lower than those in the other 3 subgroups(P<0.05),and the indicators in prospective ECG-gated+high heart rate subgroup were lower than those in retrospective ECG-gated group(including low and high heart rate subgroups)(P<0.05).Pearson correlation coefficient analysis revealed that the mean CT value,image noise,SNR,subjective image quality score had no significant correlation with heart rate,CTDIvol,DLP and ED in prospective and retrospective ECG-gated groups(P>0.05).Conclusion The subjective and objective image quality of 256-slice spiral CT coronary angiography is not correlated with radiation dose.Prospective ECG-gated scanning can reduce the radiation dose and ensure the image quality as compared with retrospective ECG-gated scanning.This holds true for eligible patients with high heart rate,and the former can effectively reduce radiation exposure.Therefore,prospective ECG-gated scanning is worthy to be promoted in clinic.

Objective:To compare the efficacy of the horizontal plate plus raft screws above the acetabulum and fixation with screws only for acetabular fractures combined with dome impaction in the aged patients.Methods:A retrospective cohort study was conducted to analyze the clinical data of 20 aged patients with acetabular fractures combined with dome impaction, who were admitted to Tianjin hospital between May 2013 and January 2023, including 5 males and 15 females, aged 61-84 years [(72.2±7.3)years]. According to Letournel and Judet classification, 13 patients had anterior column fracture, 5 anterior column fracture combined with posterior transverse fracture and 2 two-column fracture. All the patients underwent open reduction and internal fixation through an anterior approach. Of them, 11 patients were treated with the fixation with the horizonal plate plus raft screws above the acetabulum (plate plus raft screw group) and 9 with the screws only (screw only group). The operative time, intraoperative blood loss, and intraoperative fluoroscopy times were compared between the two groups. The quality of fracture reduction was evaluated with the Matta′s radiographic criteria at 3 days after surgery and the function of the hip joint was assessed with Merle D′Aubigné and Postel scoring system at 3 months after surgery and at the last follow-up as well as the excellent and good rate at te last follow-up. The occurrence of postoperative complications was observed.Results:All the patients were followed up for 6-18 months [(13.1±3.1)months]. There were no significant differences in the operative time, intraoperative blood loss or intraoperative fluoroscopy times between the two groups ( P>0.05). According to the Matta′s radiographic criteria at 3 days after surgery, patients with anatomical reduction and satisfactory reduction accounted 6 and 5 in the plate plus raft screw group, compared to 5 and 4 respectively in the screw only group ( P>0.05). The values of Merle D′Aubigné and Postel score at 3 months after surgery and at the last follow-up were (14.0±2.4)points and (15.8±2.2)points in the plate plus raft screw group, which were higher than those in the screw only group [(11.0±2.6)points and (13.0±3.1)points] ( P<0.01). The values of Merle D′Aubigné and Postel score at the last follow-up of both groups were further enhanced from those at 3 months after surgery ( P<0.01). At the last follow-up, 3 patients were rated excellent, 6 good, 1 fair and 1 poor in the plate plus raft screw group, with an excellent and good rate of 81.8%, while in the screw only group, 3 were rated good, 2 fair and 4 poor, with an excellent and good rate of 33.3% ( P<0.05). One patient in the plate plus raft screw group and 5 in the screw only group had displacement of the dome impaction fragment combined with traumatic arthritis after surgery ( P<0.05). Conclusion:For acetabular fractures combined with dome impaction in the aged patients, the horizontal plate plus raft screw above the acetabulum can effectively improve the function restoration of the hip joint and reduce the occurrence of the displacement of the dome impaction fragment and traumatic arthritis after surgery compared to the fixation with screws only.

Objective:To investigate the correlation between blood uric acid level and body composition, exercise capacity, and cardiopulmonary function in medical examination population.Methods:In this cross-sectional study, 83 individuals who underwent physical examinations at Peking University Third Hospital from June 1, 2023, to October 1, 2023, and met the inclusion criteria were included. According to whether they had hyperuricemia (HUA), the participants were divided into HUA group (53 cases) and non-HUA group (30 cases). Body composition parameters, such as body mass index and visceral fat area, were measured with a body composition analyzer. Exercise capacity indicators, including grip strength, vertical jump, back strength, and sit-and-reach test, were measured using specific monitoring devices. Cardiopulmonary function was assessed using the stair index test. The clinical characteristics of the two groups were compared with t-tests or chi-square tests, and the correlation between uric acid levels and body composition, exercise capacity, and cardiopulmonary function was analyzed. Results:The HUA group had significantly higher skeletal muscle mass, body fat mass, body mass index, and visceral fat area when compared with the non-HUA group [(31.92±5.60) vs (26.11±6.19) kg, (23.66±9.33) vs (17.19±5.00) kg, (26.53±3.68) vs (23.27±3.59) kg/m2, 91.20 (74.25, 123.90) vs 68.25 (56.25, 90.48) cm 2, respectively] (all P<0.05). The grip strength, vertical jump, and back pull strength were all lower in the HUA group [32.70 (25.25, 40.30) vs 42.35 (35.95, 48.10) kg, 30.30 (24.10, 36.48) vs 40.55 (33.06, 45.10) kg, 24.20(20.60, 32.23) vs 29.90 (25.20, 35.50) cm, 65.60 (51.75, 78.00) vs 91.00 (67.25, 111.50) kg, respectivley] (all P<0.05). The increased step index was positively correlated with reduced risk of hyperuricemia ( OR=0.875, 95% CI: 0.793-0.966) ( P<0.05). Conclusions:Blood uric acid level is correlated with cardiopulmonary function in medical examination population. Individuals with better cardiopulmonary function have a lower risk of developing HUA. However, the relationship between blood uric acid level and body composition and exercise capacity is not clear.

Abstract Tobacco use is not only harmful to adolescents physical and mental health, but is also closely related to future adults smoking prevalence, and interventions can delay the age at which adolescents take their first puff as much as possible. The article summarizes and analyzes the effectiveness of tobacco control interventions based on schools, communities or families, and a combination of multiple venues. It compares the characteristics of offline, online, and a combination of offline and online tobacco control interventions for adolescents,so as to provide references for the design and implementation of adolescent tobacco control interventions, and the effective, sustainable, and replicable adolescent tobacco control intervention models.

BACKGROUND:Hydroxyapatite is the main inorganic component of bone tissue.The polymer has the structure and function of a biomimetic extracellular matrix.The composites of hydroxyapatite and polymer have been widely studied. OBJECTIVE:To summarize the research status of hydroxyapatite composite polymer materials for bone tissue repair. METHODS:The articles collected in PubMed,Web of Science,CNKI and WanFang databases were searched from January 2010 to April 2023.The Chinese and English search terms were"hydroxyapatite,polymer,composites,degradability,bone defect,bone repair".Finally,75 articles were included for review. RESULTS AND CONCLUSION:Polymers often used in composite with hydroxyapatite for bone tissue repair include natural polymers(collagen,chitosan,alginate,serine protein,cellulose,hyaluronic acid,and polyhydroxybutyrate)and synthetic polymers[polylactic acid,polylactic acid-hydroxyacetic acid copolymer,poly(has-lactide),poly(amino acid)and poly(vinyl alcohol)].The mechanical properties and osteoinductivity of hydroxyapatite/polymer composites were improved compared with pure hydroxyapatite.Hydroxyapatite composite with polymers can be made into porous scaffolds,hydrogels,and coatings for bone repair.Hydroxyapatite/polymer composites can accelerate bone reconstruction with a slow release of loaded drugs and cytokines due to their bionic extracellular matrix structure and function.Based on the diversity of causes of bone defects and the fact that bone repair is a complex continuous process involving multiple biological factors and proteins,repair materials with mechanical properties matching bone tissue,degradation processes synchronized with bone repair,and efficient osteogenesis and vascularization need to be further investigated.

BACKGROUND:Compared with traditional two-dimensional culture,three-dimensional microtissue culture can show greater advantages.However,more favorable cultivation methods in three-dimensional culture still need to be further explored. OBJECTIVE:To evaluate the cell behavior of microtissue and its ability to promote cartilage formation under two three-dimensional culture methods. METHODS:Cartilage-derived microcarriers were prepared by chemical decellularization and tissue crushing.DNA quantification and nuclear staining were used to verify the success of decellularization,and histological staining was used to observe the matrix retention before and after decellularization.The microcarriers were characterized by scanning electron microscopy and CCK-8 assay.Cartilage-derived microtissues were constructed by combining cartilage-derived microcarriers with human adipose mesenchymal stem cells through three-dimensional static culture and three-dimensional dynamic culture methods.The cell viability and chondrogenic ability of the two groups of microtissues were detected by scanning electron microscopy,live and dead staining,and RT-qPCR. RESULTS AND CONCLUSION:(1)Cartilage-derived microcarriers were successfully prepared.Compared with before decellularization,the DNA content significantly decreased after decellularization(P<0.001).Scanning electron microscope observation showed that the surface of the microcarrier was surrounded by collagen,maintaining the characteristics of the natural extracellular matrix of cartilage cells.CCK-8 assay indicated that microcarriers had no cytotoxicity and could promote cell proliferation.(2)Scanning electron microscopy and live and dead staining results showed that compared with the three-dimensional static group,the three-dimensional dynamic group had a more extended morphology of microtissue cells,and extensive connections between cells and cells,between cells and matrix,and between matrix.(3)The results of RT-qPCR showed that the expressions of SOX9,proteoglycan,and type Ⅱ collagen in microtissues of both groups were increased at 7 or 14 days.The relative expression levels of each gene in the three-dimensional dynamic group were significantly higher than those in the three-dimensional static group at 14 days(P<0.05).At 21 days,the three-dimensional static group had significantly higher gene expression compared with the three-diomensional dynamic group(P<0.001).(4)The results showed that compared with three-dimensional static culture microtissue,three-dimensional dynamic culture microtissue could achieve higher expression of chondrogen-related genes in a shorter time,showing better cell viability and chondrogenic ability.

With the continuous development of medical science and the widespread use of antibiotics,the problem of bacterial resistance is increasing,especially the increasing carbapenem-resistant Enterobacteriaceae(CRE)infection,and the high mortality rate,which brings great challenges to clinical treatment.In this paper,the mechanism of drug resistance,existing antibac-terial drugs,and exploratory treatment options for CRE are reviewed,and the research progress in treating CRE infection is dis-cussed to provide more reliable evidence and a theoretical basis for clinical practice.