Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Objective To explore the valve regurgitation status of left heart after the implantation of left ventricular assist device (LVAD) and its effect on prognosis of patients with LVAD implantation. Methods A total of 35 patients with cardiomyopathy who underwent magnetic levitation LVAD implantation at Zhongshan Hospital, Fudan University from February 2021 to July 2024 were retrospectively selected. Clinical data during hospitalization were collected, including preoperative basic data and postoperative valve regurgitation status. Telephone follow-ups were conducted to monitor patients’ survival status and transthoracic echocardiography was used to assess left valve function. Kaplan-Meier survival curves and log-rank test were employed to compare the survival rate of patients with different levels of valve regurgitation. Results The 35 patients had a mean age of (53.9±11.1) years, with 85.7% male, and 3 patients (8.6%) died during hospitalization. Preoperatively, 17 patients (48.6%) had moderate or greater mitral regurgitation, while all 35 patients had less than moderate aortic regurgitation. One month postoperatively, thirty patients were followed up, among which 24 patients (80%) had less than moderate mitral regurgitation, including 11 cases with alleviated regurgitation compared to pre-surgery; 6 patients (20%) had moderate or greater mitral regurgitation, including 4 cases with stable regurgitation and 2 cases with progression of regurgitation compared to pre-surgery; 2 patients (6.7%) had progression of aortic regurgitation to moderate or greater. The follow-up time was 1.2 (1.0, 2.1) years, with 1-year survival rate of 91.4% and 3-year survival rate of 71.1%. Survival analysis showed that the 3-year survival rate of patients with moderate or greater mitral regurgitation one month postoperatively was significantly lower than that of patients with less than moderate regurgitation (66.7% vs 83.3%, P＝0.046). Conclusions After the implantation of magnetic levitation LVAD, most patients showed improvement in mitral regurgitation, while aortic regurgitation remained unchanged. The degree of mitral regurgitation one month postoperatively is associated with prognosis.

Background As one of the key populations in the prevention and treatment of iodine deficiency disorders, it is important to continuously monitor the iodine nutritional level of school-age children. The current reference interval for thyroid volume in China is based on age only, without taking into account differences in individual developmental levels, and the distribution of thyroid volume may vary regionally due to economic, demographic, and environmental factors. The current reference cut-off points for thyroid volume proposed by the World Health Organization are not based on the Chinese population. Objective To understand the iodine nutritional status and distribution of thyroid volume (Tvol) among children aged 8-10 years in Huangpu District, Shanghai, China, to identify impact factors of Tvol, and to propose a reference range upper limit for local thyroid health surveillance, so as to provide a basis for goiter control and prevention. Methods Six hundred children aged 8-10 years in Huangpu District were recruited in 2017, 2020, and 2023, and body height, weight, thyroid volume, urinary iodine, and iodine content of household edible salt were determined. A multilevel model was constructed using population density and area as regional variables, and age, body surface area (BSA), and body mass index (BMI) as potential impact factors for at the individual level, to assess their effects on thyroid volume. Quantile regression of thyroid volume was performed, and the 98th percentile (P₉₈) of thyroid volume was predicted based on age and BSA. Results The iodized salt coverage in the households of surveyed children in 2017, 2020, and 2023 was 72.0%, 57.0%, and 48.0%, respectively, and the iodized salt coverage decreased by year (χ²=24.31, P<0.001). The urinary iodine level of children in 2017 was higher than that in 2020 and 2023 (χ²=18.77, P<0.001). The Tvol medians of children in 2017, 2020, and 2023 were 2.29, 2.49, and 2.97 mL, respectively, and the Tvol increased by year (χ²=60.04, P<0.001). The proportion of goiter was higher in children in 2023 than in 2017 and 2020 (χ²=6.57, P<0.05). Sex differences were not statistically significant for urinary iodine levels, thyroid volume, and goiter. The median Tvol was 2.26, 2.58, and 2.76 mL in children of 8, 9, and 10 years old respectively, and the Tvol increased with age (χ²=49.02, P <0.001). Tvol was positively correlated with age, BSA, and BMI with correlation coefficients of 0.2846, 0.3723, and 0.2950, respectively. The final quantile regression model showed that the strongest effect of BSA was associated with the 98th percentile of Tvol. Multilevel models considering population density or area as regional variables failed to achieve convergence. Conclusion To establish the upper limit of the reference interval for thyroid volume of healthy children in Huangpu District, the effects of age and BSA should be considered at the individual level, and the upper limit of the normal interval for goiter screening is suggested to be the 98th percentile value of BSA at the same age. In addition, the adaptability of population density and regional area as indicators of regional aggregation of thyroid volume distribution still needs to be further explored.

BACKGROUND:Bone relies on the close connection between blood vessels and bone cells to maintain its integrity.Bones are in a physiologically hypoxic environment.Therefore,the study of angiogenesis and osteogenesis in hypoxic environment is closer to the microenvironment in vivo. OBJECTIVE:To explore the influence of Wenshen Tongluo Zhitong(WSTLZT)formula on H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell co-culture system in hypoxia environment and its related mechanism. METHODS:Enzyme digestion method and flow sorting technique were used to isolate and identify H-type bone microvascular endothelial cells.Mouse bone marrow mesenchymal stem cells were isolated and obtained by bone marrow adhesion method.H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell hypoxic co-culture system was established using Transwell chamber and anoxic culture workstation.WSTLZT formula powder was used to intervene in each group at a mass concentration of 50 and 100 μg/mL.The angiogenic function of H-type bone microvascular endothelial cells in the co-culture system was evaluated by scratch migration test and tube formation test.The osteogenic differentiation ability of bone marrow mesenchymal stem cells in the co-cultured system was evaluated by alkaline phosphatase staining and alizarin red staining.The protein and mRNA expression changes of PDGF/PI3K/AKT signal axis related molecules in H-type bone microvascular endothelial cells in the co-cultured system were detected by Western Blotting and q-PCR,respectively. RESULTS AND CONCLUSION:(1)Compared with the normal oxygen group,the scratch mobility and new blood vessel length of H-type bone microvascular endothelial cells were significantly higher(P<0.05);the osteogenic differentiation capacity of bone marrow mesenchymal stem cells was higher(P<0.05);the expression of PDGF/PI3K/AKT axis-related molecular protein and mRNA increased(P<0.05)in the hypoxia group.(2)Compared with the hypoxia group,scratch mobility and new blood vessel length were significantly increased in the H-type bone microvascular endothelial cells(P<0.05);bone marrow mesenchymal stem cells had stronger osteogenic function(P<0.05);the expression of PDGF/PI3K/AKT axis-related molecular proteins and mRNA further increased(P<0.05)after treatment with different dose concentrations of WSTLZT formula.These findings conclude that H-type angiogenesis and osteogenesis under hypoxia may be related to the PDGF/PI3K/AKT signaling axis,and WSTLZT formula may promote H-type vasculo-dependent bone formation by activating the PDGF/PI3K/AKT signaling axis,thereby preventing and treating osteoporosis.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Methods: Seventy-five patients with atlas fracture were included from January 2015 to December 2020. Based on the anatomy of the fracture line, atlas fractures were divided into three types. Each type was divided into two subtypes according to the fracture displacement. Unweighted Cohen kappa coefficients were applied to evaluate the reliability and reproducibility. Results: According to the new classification, 17 cases of type A1, 12 of type A2, seven of type B1, 13 of type B2, 12 of type C1, and 14 of type C2 were identified. The K-values of the interobserver and intraobserver reliability were 0.846 and 0.912, respectively, for the new classification. The K-values of interobserver reliability for types A, B, and C were 0.843, 0.799, and 0.898, respectively. The K-values of intraobserver reliability for types A, B, and C were 0.888, 0.910, and 0.935, respectively. The mean K-values of the interobserver and intraobserver reliability for subtypes were 0.687 and 0.829, respectively. Conclusions The new classification of atlas fractures can cover nearly all atlas fractures. This system is the first to evaluate the severity of fractures based on the C1 articular facet and fracture displacement and strengthen the anatomy ring of the atlas. It is concise, easy to remember, reliable, and reproducible.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

This study established the HPLC fingerprints, characteristic chromatograms, and a multi-component content determination method for Bidens bipinnata and B. biternata. The chemical pattern recognition analysis was then employed to clarify the characteristic indexes of quality differences between the two original plants of Bidentis Herba, providing a reference for establishing the quality standards of Bidentis Herba. HPLC was launched on an Agilent Poroshell 120 EC-C_(18) chromatographic column(4.6 mm×250 mm, 4 μm) by gradient elution with a mobile phase of 0.1% aqueous phosphoric acid-acetonitrile at a flow rate of 0.7 mL·min~(-1), detection wavelength of 270 nm, column temperature of 25 ℃, and an injection volume of 5 μL. The similarity between the fingerprints of 18 batches of Bidentis Herba samples and the common pattern(R) ranged from 0.572 to 0.933. A total of 23 chromatographic peaks were calibrated. Through comparison with the reference substances, six components(neochlorogenic acid, chlorogenic acid, isochlorogenic acid A, isochlorogenic acid B, rutin, and hyperoside) were identified and subjected to quantitative analysis. The characteristic fingerprints of B. bipinnata and B. biternata were calibrated with 20 and 17 characteristic peaks, respectively. Among them, peaks 8, 9, 22, and 23 were the characteristic peaks of B. bipinnata, and peak 7 was the characteristic peak of B. biternata, which can be used to distinguish the two original plants of Bidentis Herba. The relative standard deviation of the content of the above-mentioned six components ranged from 36% to 123%. The cluster analysis, principal component analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) classified the 18 batches of Bidentis Herba samples into two categories. Additionally, through the analysis of variable importance in projection(VIP) under OPLS-DA, three characteristic indexes, rutin, isochlorogenic acid A, and isochlorogenic acid B, were identified. The analytical method established in this study can comprehensively evaluate the consistency of Bidentis Herba samples derived from different original plants, specifically identify the differential components between them, and effectively distinguish the two original plants of Bidentis Herba, providing a basis for the differentiation between different original plants and the quality control of Bidentis Herba.
Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Bidens/chemistry*

Viral infectious diseases, characterized by their intricate nature and wide-ranging diversity, pose substantial challenges in the domain of data management. The vast volume of data generated by these diseases, spanning from the molecular mechanisms within cells to large-scale epidemiological patterns, has surpassed the capabilities of traditional analytical methods. In the era of artificial intelligence (AI) and big data, there is an urgent necessity for the optimization of these analytical methods to more effectively handle and utilize the information. Despite the rapid accumulation of data associated with viral infections, the lack of a comprehensive framework for integrating, selecting, and analyzing these datasets has left numerous researchers uncertain about which data to select, how to access it, and how to utilize it most effectively in their research.This review endeavors to fill these gaps by exploring the multifaceted nature of viral infectious diseases and summarizing relevant data across multiple levels, from the molecular details of pathogens to broad epidemiological trends. The scope extends from the micro-scale to the macro-scale, encompassing pathogens, hosts, and vectors. In addition to data summarization, this review thoroughly investigates various dataset sources. It also traces the historical evolution of data collection in the field of viral infectious diseases, highlighting the progress achieved over time. Simultaneously, it evaluates the current limitations that impede data utilization.Furthermore, we propose strategies to surmount these challenges, focusing on the development and application of advanced computational techniques, AI-driven models, and enhanced data integration practices. By providing a comprehensive synthesis of existing knowledge, this review is designed to guide future research and contribute to more informed approaches in the surveillance, prevention, and control of viral infectious diseases, particularly within the context of the expanding big-data landscape.
Big Data ; Humans ; Virus Diseases/virology* ; Artificial Intelligence

OBJECTIVES: To identify risk factors contributing to prolonged postoperative length of stay (LOS) in very elderly patients following hip fracture surgery, with a focus on postoperative complications and the impact of different anesthesia approaches. METHODS: This retrospective single-center cohort study enrolled patients aged 90 years or older who underwent hip fracture surgery at Peking Union Medical College Hospital between January 31, 2013 and December 31, 2023. Relevant perioperative data were collected. The primary outcome was postoperative LOS, and the study cohort was divided into two groups: postoperative LOS ≤ 7 days and LOS > 7 days. Logistic regression was performed to identify factors related to prolonged postoperative LOS. RESULTS: A total of 155 patients were included. The average age was 92.7 ± 2.6 years. There were 73 (47%) patients with postoperative LOS > 7 days. Postoperative pneumonia was the only factor associated with a prolonged postoperative LOS (OR = 2.12, 95% CI [1.09, 4.16], P = 0.028). Neither the type of anesthesia (regional vs. general anesthesia, OR = 1.00, 95% CI [0.53, 1.90], P = 0.993) nor the method of airway management (laryngeal mask ventilation vs. spontaneous breathing, OR = 1.46, 95% CI [0.58, 3.76], P = 0.424; endotracheal intubation vs. spontaneous breathing, OR = 0.82, 95% CI [0.39, 1.69], P = 0.592) showed a significant association with a prolonged postoperative LOS. Preoperative chronic obstructive pulmonary disease (OR = 2.78, 95% CI [1.05, 7.65], P = 0.040) and preoperative neutrophil count (OR = 1.13, 95% CI [1.01, 1.26], P = 0.029) were both significantly associated with the occurrence of postoperative pneumonia, while anesthesia type and airway management method were not. CONCLUSIONS Postoperative pneumonia was associated with prolonged postoperative LOS in very elderly patients undergoing hip fracture surgery, whereas anesthesia types and airway management methods show no association with prolonged postoperative LOS or postoperative pneumonia. Preoperative comorbidities, especially respiratory conditions and systemic inflammation, potentially play a substantial role in postoperative recovery.
Humans ; Hip Fractures/surgery* ; Aged, 80 and over ; Risk Factors ; Length of Stay ; Female ; Male ; Retrospective Studies ; Postoperative Complications/etiology*