BACKGROUND:How to effectively promote bone regeneration and bone reconstruction after bone injury has always been a key issue in clinical bone repair research.The use of biological and degradable materials loaded with bioactive factors to treat bone defects has excellent application prospects in bone repair. OBJECTIVE:To investigate the effect of polylactic acid-glycolic acid copolymer(PLGA)composite scaffold modified by lysine-grafted graphene oxide nanoparticles(LGA-g-GO)on osteogenic differentiation and new bone formation. METHODS:PLGA was dissolved in dichloromethane and PLGA scaffold was prepared by solvent evaporation method.PLGA/GO composite scaffolds were prepared by dispersing graphene oxide uniformly in PLGA solution.LGA-g-GO nanoparticles were prepared by chemical grafting method,and the PLGA/LGA-g-GO composite scaffolds were constructed by blending LGA-g-GO nanoparticles at different mass ratios(1%,2%,and 3%)with PLGA.The micromorphology,hydrophilicity,and protein adsorption capacity of scaffolds of five groups were characterized.MC3T3 cells were inoculated on the surface of scaffolds of five groups to detect cell proliferation and osteogenic differentiation. RESULTS AND CONCLUSION:(1)The surface of PLGA scaffolds was smooth and flat under scanning electron microscope,while the surface of the other four scaffolds was rough.The surface roughness of the composite scaffolds increased with the increase of the addition of LGA-g-GO nanoparticles.The water contact angle of PLGA/LGA-g-GO(3%)composite scaffolds was lower than that of the other four groups(P<0.05).The protein adsorption capacity of PLGA/LGA-g-GO(1%,2%,and 3%)composite scaffolds was stronger than PLGA and PLGA/GO scaffolds(P<0.05).(2)CCK-8 assay showed that PLGA/LGA-g-GO(2%,3%)composite scaffold could promote the proliferation of MC3T3 cells.Alkaline phosphatase staining and alizarin red staining showed that the cell alkaline phosphatase activity in PLGA/LGA-g-GO(2%,3%)group was higher than that in the other three groups(P<0.05).The calcium deposition in the PLGA/GO and PLGA/LGA-g-GO(1%,2%,and 3%)groups was higher than that in the PLGA group(P<0.05).(3)In summary,PLGA/LGA-g-GO composite scaffold can promote the proliferation and osteogenic differentiation of osteoblasts,and is conducive to bone regeneration and bone reconstruction after bone injury.

In recent years, the application of artificial intelligence (AI) in the field of biology has witnessed remarkable advancements. Among these, the most notable achievements have emerged in the domain of protein structure prediction and design, with AlphaFold and related innovations earning the 2024 Nobel Prize in Chemistry. These breakthroughs have transformed our ability to understand protein folding and molecular interactions, marking a pivotal milestone in computational biology. Looking ahead, it is foreseeable that the accurate prediction of various physicochemical properties of proteins—beyond static structure—will become the next critical frontier in this rapidly evolving field. One of the most important protein properties is thermodynamic stability, which refers to a protein’s ability to maintain its native conformation under physiological or stress conditions. Accurate prediction of protein stability, especially upon single-point mutations, plays a vital role in numerous scientific and industrial domains. These include understanding the molecular basis of disease, rational drug design, development of therapeutic proteins, design of more robust industrial enzymes, and engineering of biosensors. Consequently, the ability to reliably forecast the stability changes caused by mutations has broad and transformative implications across biomedical and biotechnological applications. Historically, protein stability was assessed via experimental methods such as differential scanning calorimetry (DSC) and circular dichroism (CD), which, while precise, are time-consuming and resource-intensive. This prompted the development of computational approaches, including empirical energy functions and physics-based simulations. However, these traditional models often fall short in capturing the complex, high-dimensional nature of protein conformational landscapes and mutational effects. Recent advances in machine learning (ML) have significantly improved predictive performance in this area. Early ML models used handcrafted features derived from sequence and structure, whereas modern deep learning models leverage massive datasets and learn representations directly from data. Deep neural networks (DNNs), graph neural networks (GNNs), and attention-based architectures such as transformers have shown particular promise. GNNs, in particular, excel at modeling spatial and topological relationships in molecular structures, making them well-suited for protein modeling tasks. Furthermore, attention mechanisms enable models to dynamically weigh the contribution of specific residues or regions, capturing long-range interactions and allosteric effects. Nevertheless, several key challenges remain. These include the imbalance and scarcity of high-quality experimental datasets, particularly for rare or functionally significant mutations, which can lead to biased or overfitted models. Additionally, the inherently dynamic nature of proteins—their conformational flexibility and context-dependent behavior—is difficult to encode in static structural representations. Current models often rely on a single structure or average conformation, which may overlook important aspects of stability modulation. Efforts are ongoing to incorporate multi-conformational ensembles, molecular dynamics simulations, and physics-informed learning frameworks into predictive models. This paper presents a comprehensive review of the evolution of protein thermodynamic stability prediction techniques, with emphasis on the recent progress enabled by machine learning. It highlights representative datasets, modeling strategies, evaluation benchmarks, and the integration of structural and biochemical features. The aim is to provide researchers with a structured and up-to-date reference, guiding the development of more robust, generalizable, and interpretable models for predicting protein stability changes upon mutation. As the field moves forward, the synergy between data-driven AI methods and domain-specific biological knowledge will be key to unlocking deeper understanding and broader applications of protein engineering.

The cdc73(cell division cycle 73)gene encodes the RNA polymerase Ⅱ cofactor Cdc73 in fis-sion yeast(Schizosaccharomyces Pombe),and is involved in G2 checkpoint activation and regulates the cell cycle.However,whether Cdc73 regulates cell mitotic dynamics is unknown.In this study,fluores-cent protein labeling and live cell imaging techniques were used to investigate the effects of cdc73 deletion on sexual reproduction and the dynamics of microtubules,actin,mitochondria,and histones during mito-sis.The results showed that in sexual reproduction,cdc73 deletion resulted in a 14.23％increase in the length of ascospores and a 64.08％decrease in the number of cells producing four spores.Analysis of the live cell imaging results revealed that,in mitosis,the elongation length of microtubules in anaphase was shortened by 11.21％,and the elongation time was reduced by 17.39％;the formation and contraction rates of actin rings decreased by 33.33％and 26.09％,respectively,and the formation and contraction times were prolonged by 58.00％and 40.38％,respectively.Meanwhile,the expression levels of actin ring,mitochondrion,and histones also increased.This study revealed the cdc73 deletion inhibits spindle elongation and delays actin ring formation and contraction in mitosis,which provides some scientific basis for further exploring the involvement of Cdc73 in regulating microtubule and actin dynamics in cell divi-sion.

Japan is one of the main trading partners for the import and export of experimental animals in China,and its quarantine and supervision policies for the import and export of experimental animals are very detailed and strict.This article takes experimental dogs,cats,and monkeys as examples to provide an in-depth analysis of the quarantine and supervision policies for the main experimental animals exported to Japan.At the same time,it reflects on the current laws and regulations,import and export management method,standards,biosafety,breeding and management status,as well as the import and export business status of experimental animals in China.Suggestions are provided in improving the laws and regulations,import and export management method,ensuring national biosafety,improving the management level of experimental animal breeding,and promoting the import and export trade of experimental animals,in order to provide reference for comprehensively improving the production,use,and breeding management level of experimental animals in China and strengthening the trade between China and Japan.

Objective:To prepare mesenchymal stem cells with antioxidant capacity (AO-MSC ) from human umbilical cords and evaluate its cell biological properties.Methods:In control group,mesenchymal stem cells (MSC) were isolated by digesting human umbilical cord Wharton's Jelly tissues with 0.2％ collagenase Ⅱ,and the released cells were collected and cultured in an animal serum-free culture medium.In AO-MSC group,incompletely collagenase Ⅱ-digested tissue debris were allowed to adhere to flusk flat bottoms and the AO-MSC was harvested by adherent culture. The conventional digestion and culture method was used as control.MSC colony forming ability was evaluated by fibroblast colony forming assay (CFU-F).MSC proliferative capacity was evaluated by CCK-8 assay.The MSC surface markers were detected by using flow cytometry and immunofluorescence staining.The adipogenic and osteogenic capacity of MSC was evaluated by multi-differentiation in vitro,and the mRNA expression of genes that control adipogenic and osteogenic differentiation was detected by real-time fluorescence quantitative PCR (RT-qPCR );Moreover,the mRNA expression of antioxidant substances such as SOD-1,GSH,GAT,and NQO1 in MSC was also evaluated by RT-qPCR.Results:The AO-MSC isolated by this strategy reached a confluence of 80％-90％ at around 18 days and grew in a swirling pattern.Flow cytometry and immunofluorescence staining assays showed that CD73,CD29,CD105,CD90 were highly expressed and CD31,CD45,HLA-DR were scarcely expressed in AO-MSC.AO-MSC exhibited stronger self-renewal and differentiation ability compared to MSC.However,the in vitro adipogenic-osteogenic capacity of MSC in the control group was stronger than that of AO-MSC.RT-qPCR assay showed that AO-MSC expressed higher mRNA levels of antioxidant substances compared to MSC.Conclusion:Human AO-MSC is successfully prepared from human umbilical cord without animal serum.

Objective The researchers systematically retrieved,evaluated,and summarized the best evidence for the care of nebulized inhalation in adult patients on mechanical ventilation,to provide a basis for standardizing the care of nebulized inhalation in patients on mechanical ventilation.Methods We systematically searched the domestic and foreign databases to collect the evidence on the literature related to nebulization therapy for mechanical ventilation in adults.The time for the retrieval is from the inception of databases until February 2023.There were 3 researchers who evaluated the quality of the literature,and extracted and summarized the evidence based on this subject.Results A total of 19 articles were obtained in database.42 pieces of evidence were summarized,covering pre-assessment of nebulized inhalation,preparation before nebulized inhalation,medication management,selection and standardized use of nebulization devices,respiratory machine mode and parameter settings,equipment management during nebulized inhalation,evaluation of effect,management of adverse reactions,disposal of materials and environment after nebulized inhalation and management of nebulized inhalation for respiratory infectious diseases.Conclusion This study summarized the best evidence for nebulized inhalation nursing in adult patients with mechanical ventilation,so as to provide a reference of standardized nebulized inhalation therapy for such patients,which is conducive to ensuring the safety of patients.

AIM To investigate the effects of Zuogui Jiangtang Tongmai Recipe on necroptosis pathway in a rat model of type 2 diabetes mellitus(T2DM)complicated with cerebral infarction(CI).METHODS The SD rats were randomly divided into the sham operation group,the model group,the metformin group(0.045 g/kg),and the low,medium and high dose Zuogui Jiangtang Tongmai Recipe groups(6.5,13,26 g/kg),with 9 rats in each group.In contrast to rats of the sham operation group,rats of the other groups were given 4 weeks feeding of high-sugar and high-fat diet combined with intraperitoneal injection of streptozotocin to establish a T2DM rat model with one week stable blood glucose,followed by gavage of corresponding drugs 3 days before the establishment of the middle cerebral artery occlusion(MCAO)model.After 7 days of administration,the rats had their CI injury assessed by mNSS method and TTC staining;their level of blood glucose detected by blood glucose meter;their levels of glycated serum protein,serum TNF-α and IL-1β detected by ELISA;their cerebral mRNA expressions of FADD,RIPK1,RIPK3 and MLKL detected by RT-qPCR;and their cerebral protein expressions of FADD,p-RIPK1,p-RIPK3 and p-MLKL detected by Western blot.RESULTS Compared with the sham operation group,the model group displayed increased levels of blood glucose value,glycosylated serum protein,neurological function score,cerebral infarction volume,cerebral FADD,RIPK1,RIPK3 and MLKL mRNA expressions,cerebral FADD,p-RIPK1,p-RIPK3 and p-MLKL protein expressions,serum TNF-α and IL-1β levels(P＜0.01);and more disordered and morphologically diverse neurons with smaller nucleus.Compared with the model group,the groups intervened with medium or high dose Zuogui Jiangtang Tongmai Recipe,or metformin shared improvement in terms of the aforementioned indices(P＜0.05,P＜0.01);and more neurons with regular morphology neat arrangement,and reduced cell gap.CONCLUSION Zuogui Jiangtang Tongmai Recipe can improve the neurological dysfunction of the rat model of T2DM complicated with CI,which may associate with the inhibited activation of necroptosis signaling pathway.

Objective:To investigate the influence of curative-intent resection with textbook outcomes of liver surgery (TOLS) on long-term prognosis of gallbladder carcinoma (GBC).Methods:The retrospective cohort study was conducted. The clinicopathological data of 824 patients with GBC in the national multicenter database of Biliary Surgery Group of Elite Group of Chinese Journal of Digestive Surgery, who were admitted to 15 medical centers from January 2014 to January 2021, were collected. There were 285 males and 539 females, aged (62±11)years. According to the evalua-tion criteria of TOLS, patients were divided into those who achieved TOLS and those who did not achieve TOLS. Measurement data with normal distribution were represented as Mean± SD, and com-parison between groups was conducted using the independent sample t test. Measurement data with skewed distribution were represented as M( Q1, Q3), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data were conduc-ted using the Mann-Whitney U test. The Kaplan-Meier method was used to calculate survival rate and draw survival curve, and the Log-rank test was used for survival analysis. The COX stepwise regression model with backward Wald method was used for univariate and multivariate analyses. Results:(1) Achievement of TOLS. Of the 824 patients undergoing curative-intent resection for GBC, there were 510 cases achieving TOLS and 314 cases not achieving TOLS. (2) Follow-up. Of the 824 patients undergoing curative-intent resection for GBC, after excluding 112 deaths within 90 days after discharge, 712 cases were included for the survival analysis. The median follow-up time, median overall survival time and 5-year overall survival rate of the 510 patients achieving TOLS were 22.1(11.4,30.1)months, 47.6(30.6,64.6)months and 47.5%. The median follow-up time, median overall survival time and 5-year overall survival rate of the 202 patients not achieving TOLS were 14.0(6.8,25.5)months, 24.3(20.0,28.6)months and 21.0%. There was a significant difference in overall survival between patients achieving TOLS and patients not achieving TOLS ( χ2=58.491, P<0.05). (3) Analysis of factors influencing prognosis of patients. Results of multivariate analysis showed that TOLS, carcinoembryonic antigen (CEA), CA19-9, poorly differentiation of tumor, T2 stage of eighth edition of American Joint Committee on Cancer (AJCC) staging, T3 and T4 stage of eighth edition of AJCC staging, N1 stage of the eighth edition of AJCC staging, N2 stage of the eighth edition of AJCC staging, adjuvant therapy were independent factors influencing overall survival time of patients undergoing curative-intent resection for GBC ( hazard ratio=0.452, 1.479, 1.373, 1.612, 1.455, 1.481, 1.835, 1.978, 0.538, 95% c onfidence interval as 0.352-0.581, 1.141-1.964, 1.052-1.791, 1.259-2.063, 1.102-1.920, 1.022-2.147, 1.380-2.441, 1.342-2.915, 0.382-0.758, P<0.05). Conclusion:Patients under-going curative-intent resection for GBC with TOLS can achieve better long-term prognosis.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

Nuclear medicine plays an indispensable role in the diagnosis,treatment,and prognosis of a wide range of diseases.Nuclear medicine using radionuclides for diagnosis has the advantages of accuracy,speed,high sensitivity and high resolution.Currently,several radionuclides play pivotal roles in disease diagnosis.This article primarily examines the clinical application and research of diagnostic radionuclides,including 18 F,89 Zr,68 Ga,99m Tc,131 I,123 I,and 11 C.The objective is to offer valuable insights for disease diagnosis and staging of diseases.