Objective: To design and establish a new method for flow cytometry-based detection of commonly observed highly expressed antigens on red blood cells, and to further evaluate the differences and distribution characteristics of antigen expression levels between ABO blood type homozygotes and heterozygotes in healthy individuals. Methods: Residual blood samples after donor blood type identification by Shanghai Blood Center in April 2024 were collected. Among them, samples of 19 homozygous and 19 heterozygous individuals of type A and type B were selected. Then the expression level of ABO antigen on red blood cells were detected using the new method established in this study and the traditional aldehyde fixed red blood cell method. Both methods were tested independently three times and the results were compared. Results: The mean values of the three detection results of the new method was (×10 /RBC): AA homozygous 3.3±0.5, AO heterozygous 2.8±0.3, BB homozygous 3.6±0.3, BO heterozygous 3.1±2.8. The mean values of the three detection results of the aldehyde fixation method were AA homozygous 5.9±0.9, AO heterozygous 5.0±1.4, BB homozygous 3.8±0.6, and BO heterozygous 3.3±0.4. The average antigen distribution of each genotype followed a normal distribution. Comparing the average antigen expression levels of homozygotes and heterozygotes, both methods showed that A/B homozygotes had higher antigen levels than heterozygotes, with AA being 1.17 to 1.18 times that of AO and BB being 1.15 to 1.16 times that of BO. Comparing the inter batch differences in the three test results of two methods, the new method showed no significant difference in the three test results for four genotypes (P>0.05). The aldehyde fixation method showed significant differences in the test results for all three genotypes (P<0.01) except for BB homozygotes (P>0.05). The reliability and reproducibility of the new method were better than those of the traditional aldehyde fixation method. Conclusion: The antigen expression level of ABO homozygotes is higher than that of heterozygotes, and the difference in antigen level between type A homozygotes and heterozygotes is slightly higher than that of type B. The new method is superior to traditional aldolization fixation methods.

Animal experiments are widely used in biomedical research for safety assessment, toxicological analysis, efficacy evaluation, and mechanism exploration. In recent years, the ethical review system has become more stringent, and awareness of animal welfare has continuously increased. To promote more efficient and cost-effective drug research and development, the United States passed the Food and Drug Administration (FDA) Modernization Act 2.0 in September 2022, which removed the federal mandate requiring animal testing in preclinical drug research. In April 2025, the FDA further proposed to adopt a series of "new alternative methods" in the research and development of drugs such as monoclonal antibodies, which included artificial intelligence computing models, organoid toxicity tests, and 3D micro-physiological systems, thereby gradually phasing out traditional animal experiment models. Among these cutting-edge technologies, 3D bioprinting models are a significant alternative and complement to animal models, owing to their high biomimetic properties, reproducibility, and scalability. This review provides a comprehensive overview of advancements and applications of 3D bioprinting technology in the fields of biomedical and pharmaceutical research. It starts by detailing the essential elements of 3D bioprinting, including the selection and functional design of biomaterials, along with an explanation of the principles and characteristics of various printing strategies, highlighting the advantages in constructing complex multicellular spatial structures, regulating microenvironments, and guiding cell fate. It then discusses the typical applications of 3D bioprinting in drug research and development,including high-throughput screening of drug efficacy by constructing disease models such as tumors, infectious diseases, and rare diseases, as well as conducting drug toxicology research by building organ-specific models such as those of liver and heart. Additionally,the review examines the role of 3D bioprinting in tissue engineering, discussing its contributions to the construction of functional tissues such as bone, cartilage, skin, and blood vessels, as well as the latest progress in regeneration and replacement. Furthermore, this review analyzes the complementary advantages of 3D bioprinting models and animal models in the research of disease progression, drug mechanisms, precision medicine, drug development, and tissue regeneration, and discusses the potential and challenges of their integration in improving model accuracy and physiological relevance. In conclusion, as a cutting-edge in vitro modeling and manufacturing technology, 3D bioprinting is gradually establishing a comprehensive application system covering disease modeling, drug screening, toxicity prediction, and tissue regeneration.

Animal experiments are widely used in biomedical research for safety assessment, toxicological analysis, efficacy evaluation, and mechanism exploration. In recent years, the ethical review system has become more stringent, and awareness of animal welfare has continuously increased. To promote more efficient and cost-effective drug research and development, the United States passed the Food and Drug Administration (FDA) Modernization Act 2.0 in September 2022, which removed the federal mandate requiring animal testing in preclinical drug research. In April 2025, the FDA further proposed to adopt a series of "new alternative methods" in the research and development of drugs such as monoclonal antibodies, which included artificial intelligence computing models, organoid toxicity tests, and 3D micro-physiological systems, thereby gradually phasing out traditional animal experiment models. Among these cutting-edge technologies, 3D bioprinting models are a significant alternative and complement to animal models, owing to their high biomimetic properties, reproducibility, and scalability. This review provides a comprehensive overview of advancements and applications of 3D bioprinting technology in the fields of biomedical and pharmaceutical research. It starts by detailing the essential elements of 3D bioprinting, including the selection and functional design of biomaterials, along with an explanation of the principles and characteristics of various printing strategies, highlighting the advantages in constructing complex multicellular spatial structures, regulating microenvironments, and guiding cell fate. It then discusses the typical applications of 3D bioprinting in drug research and development,including high-throughput screening of drug efficacy by constructing disease models such as tumors, infectious diseases, and rare diseases, as well as conducting drug toxicology research by building organ-specific models such as those of liver and heart. Additionally,the review examines the role of 3D bioprinting in tissue engineering, discussing its contributions to the construction of functional tissues such as bone, cartilage, skin, and blood vessels, as well as the latest progress in regeneration and replacement. Furthermore, this review analyzes the complementary advantages of 3D bioprinting models and animal models in the research of disease progression, drug mechanisms, precision medicine, drug development, and tissue regeneration, and discusses the potential and challenges of their integration in improving model accuracy and physiological relevance. In conclusion, as a cutting-edge in vitro modeling and manufacturing technology, 3D bioprinting is gradually establishing a comprehensive application system covering disease modeling, drug screening, toxicity prediction, and tissue regeneration.

BACKGROUND:Currently,a variety of mesenchymal stem cells have been confirmed to have the effect of promoting wound repair,but there is still a lack of relevant research on whether placenta-derived mesenchymal stem cells can promote acute skin wound healing. OBJECTIVE:To investigate the effect of placenta-derived mesenchymal stem cell transplantation on the healing of acute skin wound in rats. METHODS:Twenty SD rats were divided into PBS group and stem cell group by the random number table method,with 10 rats in each group.All rats were selected to establish a full-thickness skin defect model.In the PBS group and stem cell group,PBS buffer and placenta-derived mesenchymal stem cells were immediately injected on the wound surface and wound margin immediately and on day 8 after modeling.The wound healing was observed immediately and on days 2,4,6,8,10,12,and 14 after modeling.The skin tissue of the wound surface was taken on day 14 and treated with hematoxylin-eosin staining,Masson staining,immunohistochemical staining and immunofluorescence staining. RESULTS AND CONCLUSION:(1)The wound surface of the rats in each group decreased with the prolongation of treatment time.The wound healing rate and wound epithelization rate of the stem cell group at 14 days were higher than those of the PBS group(P<0.01),and the wound contracture rate was lower than that of the PBS group(P<0.01).(2)The results of hematoxylin-eosin staining showed that the skin wound healing of the stem cell group was better than that of the PBS group;the degree of wound epithelization was higher,and the morphology of collagen fibers was close to that of normal skin.(3)Masson staining results showed that compared with the PBS group,collagen fibers in the skin wound tissue of the stem cell group were significantly increased and thicker,and the content of collagen fibers in the new tissue was significantly higher than that of the PBS group(P<0.01).(4)Immunohistochemical staining showed that the number of new capillaries in the stem cell group was higher than that in the PBS group(P<0.01),while the expressions of tumor necrosis factor-α and interleukin-6 were lower than those in the PBS group(P<0.01).(5)Immunofluorescence staining showed that the number of M2 macrophages in the new wounds of the stem cell group was higher than that of the PBS group(P<0.01),while the number of M1 macrophages was less than that in the PBS group(P<0.01).These findings indicate that placenta-derived mesenchymal stem cells can accelerate skin wound healing,promote wound epithelization,and reduce wound contracture,which may be related to the promotion of capillary angiogenesis,regulation of collagen fiber production,inhibition of inflammation,and regulation of macrophage polarization to M2 type.

Objective To observe the clinical efficacy of"three modulation acupuncture"combined with repeated functional magnetic stimulation(rFMS)in the treatment of neurogenic bladder with detrusor muscle weakness after spinal cord injury.Methods A total of 120 patients with neurogenic bladder with detrusor muscle weakness after spinal cord injury were divided into conventional treatment group,"three modulation acupuncture"treatment group,rFMS treatment group and comprehensive treatment group according to the random number table method,with 30 patients per group.The conventional treatment group was given conventional rehabilitation treatment,the"three modulation acupuncture"treatment group was treated with"three modulation acupuncture"(modulating spirit,modulating reflex arc,and modulating lower jiao and waterway)based on conventional rehabilitation treatment,the rFMS treatment group was treated with rFMS based on conventional rehabilitation treatment,and the comprehensive treatment group was treated with"three modulation acupuncture"and rFMS based on conventional rehabilitation treatment.The first desire to void(FDV),maximum cystometric capacity(MCC),maximum detrusor pressure of urine storage period(Pdet.max),maximum intravesical pressure of urine storage period(Pves.max),average daily urination frequency,average daily urine leakage,residual urine volume,and neurogenic bladder symptom scores of the patients were compared before and after treatment,and the clinical effectiveness of each group was evaluated.Results After treatment,the FDV,MCC,and Pdet.max of the four groups were all increased compared with those before treatment,and Pves.max,the average daily urination frequency,the average daily frequency of urine leakage,the residual urine volume,and the neurogenic bladder symptom scores were all decreased(P<0.05).After treatment,the FDV,MCC,and Pdet.max of the"three modulation acupuncture"treatment group,the rFMS treatment group and the comprehensive treatment group were all higher than those of the conventional treatment group,and Pves.max,the average daily urination frequency,the average daily frequency of urine leakage,the residual urine volume,and the neurogenic bladder symptom scores were all lower(P<0.05).After treatment,the comprehensive treatment group had a higher FDV,MCC,and Pdet.max than the"three modulation acupuncture"treatment group and rFMS treatment group,and Pves.max,the average daily urination frequency,the average daily frequency of urine leakage,the residual urine volume,and the neurogenic bladder symptom scores were lower(P<0.05).The curative efficiency rates were 86.2%(25/29)in the"three modulation acupuncture"treatment group,85.7%(24/28)in the rFMS treatment group,and 92.6%(25/27)in the comprehensive treatment group,which was higher than that of the conventional treatment group,which was 75.9%(22/29).Conclusion"Three modulation acupuncture"and rFMS can effectively improve the functional status of the bladder in patients of neurogenic bladder with detrusor muscle weakness after spinal cord injury,and their combined application has a synergistic effect.

Objective To investigate the clinical value of coronary computed tomography angiography(CCTA)based CT derived fractional flow reserve(CT-FFR)and ΔCT-FFR in improving the diagnostic efficiency for coronary abnormal hemodynamics in patients with severe calcification.Methods We retrospectively analyzed the clinical data of coronary artery disease(CAD)patients who underwent CCTA,CT-FFR,invasive coronary angiography(ICA)and FFR during hospitalization from January 2018 to June 2019 in Chinese PLA General Hospital.Severe calcification was defined as coronary artery calcium score(CACS)≥100 on single vessel level.A total of 107 CAD patients with 149 coronary arteries were included in the present study.The enrolled coronary arteries were assigned to CACS≥100 group(n=56)and CACS<100 group(n=93).CT-FFR was performed on the deep FFR platform based on machine learning(ML)algorithms and ΔCT-FFR was defined as CT-FFR difference between proximal and distal to the coronary lesion.The correlation and consistency between CT-FFR and FFR values were analyzed by Pearson and Bland-Altman methods.We attempted to analyze the incremental value of ΔCT-FFR for coronary functional evaluation,especial for coronary arteries with severe calcification,regarding FFR≤0.8 as the diagnostic gold standard.Comparison of receiver operating characteristic curves(ROC)between different diagnostic methods was presented by Delong test.Results Pearson and Bland-Altman analyses showed appreciable correlation(CACS≥100 group,r=0.71,P<0.01;CACS<100 group,r=0.73,P<0.01)and consistency(CACS≥100 group,Mean=-0.01,P=0.25;CACS<100 group,Mean=0,P=0.96)between CT-FFR and FFR values in both groups.FFR(0.80±0.08 vs.0.84±0.09,P=0.004)and CT-FFR(0.81±0.06 vs.0.85±0.06,P<0.001)levels were significant lower in CACS≥100 group than those in CACS<100 group,while ΔCT-FFR(0.14±0.06 vs.0.09±0.06,P<0.001)levels were significant higher in CACS≥100 group.Moreover,the diagnostic efficiency of CT-FFR in CACS≥100 group was inferior to that in CACS<100 group[AUC=0.792(95%CI 0.663-0.889)vs.AUC=0.929(95%CI 0.856-0.972),P=0.04],while it achieved significant improvement after ΔCT-FFR adjustment[AUC=0.876(95%CI 0.760-0.949)vs.AUC=0.792(95%CI 0.663-0.889),P=0.02]and was similar to that in CACS<100 group(P=0.37).Conclusion For coronary arteries with severe calcification,CT-FFR demonstrated significant incremental value in improving the diagnostic efficiency of coronary abnormal hemodynamics after ΔCT-FFR adjustment.

Objective To study the pharmacokinetic characteristics of the test formulation of compound lidocaine cream and reference formulation of lidocaine and prilocaine cream in Chinese healthy subjects and to evaluate whether there is bioequivalence between the two formulations.Methods A single-center,single-dose,randomized,open-label,two-period,two-sequence,crossover design was used.This study included 40 healthy subjects,and in each period,test formulation or reference formulation 60 g was applied to the skin in front of both thighs(200 cm2 each side,a total of 400 cm2)under fasting conditions,and the drug was left on for at least 5 h after application.The concentrations of lidocaine and prilocaine in plasma were determined using liquid chromatography-tandem mass spectrometry(LC-MS/MS)method.Pharmacokinetic parameters were calculated using WinNonlin 8.0 software to evaluate the bioequivalence of the two formulations.Results After the application of the test formulation compound lidocaine cream and the reference formulation lidocaine and prilocaine cream on both thighs of the subjects,the pharmacokinetic parameters of lidocaine in plasma were as follows:Cmax were(167.27±91.33)and(156.13±66.86)ng·mL-1,AUC0-t were(1 651.78±685.09)and(1 636.69±617.23)ng·mL-1·h,AUC0-∞ were(1 669.85±684.65)and(1 654.37±618.30)ng·mL-1·h,the adjusted geometric mean ratios were 104.49％,101.88％and 101.89％,respectively,with 90％confidence intervals of 98.18％-111.20％,97.80％-106.13％and 97.87％-106.07％,all within the range of 80.00％-125.00％.The pharmacokinetic parameters of prilocaine in plasma were as follows:Cmax were(95.66±48.84)and(87.52±39.16)ng·mL-1,AUC0-t were(790.86±263.99)and(774.14±256.42)ng·mL-1·h,AUC0_m were(807.27±264.67)and(792.84±254.06)ng·mL-1 h,the adjusted geometric mean ratios were 107.34％,103.55％and 102.98％,respectively with 90％confidence intervals of 101.69％-113.31％,99.94％-107.30％and 99.65％-106.43％,all within the range of 80.00％-125.00％.Conclusion The test formulation compound lidocaine cream and the reference formulation lidocaine and prilocaine cream are bioequivalent.

As the backbone force of China's social and economic construction, the health status of workers is closely related to the nation's productivity and social development. Currently, cancers have become one of the major diseases threatening the health of workers. However, there are still many shortcomings in the cancer screening services for the workers. To standardize cancer screening services for workers, ensure the quality of screening services, and improve the overall screening effectiveness, 19 institutions, including Peking Union Medical College Hospital of the Chinese Academy of Medical Sciences, have jointly formulated the Group Standard "Specification for service of cancer screening for workers (T/CHAA 023-2023)". This standard follows the principles of "legality, scientific rigor, advancement, and feasibility" and combines the frontier scientific advances in cancer screening. It clarifies the relevant requirements for service principles, service design, service delivery, service management, service evaluation, and improving worker cancer screening. Implementing this group standard will help connect the common screening needs of workers, employers, and cancer screening service providers, standardize the screening process, improve screening quality, and ultimately increase the early diagnosis rate and survival rate of cancer patients. Consequently, this group standard will help safeguard workers' health rights and interests, ensure the labor force resources, promote the comprehensive coordinated and sustainable development of society, and contribute to realizing the "Healthy China 2030" strategic policy.

Objective:To develop a grading system for necrosis of pedicled flaps in reconstruction of foot and ankle, and to verify its effectiveness and repeatability.Methods:A retrospective observational study was conducted. A total of 40 necroses of foot and ankle pedicled flaps were selected by 2 senior surgeons based on the flap surgery performed by the same surgical group in Department of Orthopaedic Surgery, the 920 Hospital of Joint Logistic Support Force of PLA from January 2010 to January 2022. A grading system for pedicled flap necrosis was proposed by a working group and the 40 necrotic flaps were graded. The coincidence rate was calculated to evaluate the effectiveness of the grading system through correlation studies between grading and clinical treatment. One photo of a typical postoperative necrotic flap was collected from each of the 40 flaps. Then 5 extramural surgeons were asked to grade the necroses shown on the photos according to the proposed grading system. Moreover, weighted Kappa analysis was performed on the results of proposed grading system and also on the standard grading currently in use, to evaluate the repeatability of the proposed grading system. Evaluated data were expressed by Mean±SD, and the coincidence rate was expressed by percentage. The reproducibility was studied by weighted Kappa analysis.Results:Of the 40 necrotic flaps, 7 flaps were classified in Grade I, 16 in Grade Ⅱ, 12 in Grade Ⅲ and 5 in Grade IV. In comparison with the actual treatment methods, the overall coincidence rate of the grading system was 92.5%. It indicated that the proposed grading system could effectively guide the selection of a treatment procedure. The average weighted Kappa coefficient of surgeons was at 0.628 with a 95% confidence interval (95%CI) between 0.460-0.796, which was strongly consistent with the standard of the grading system currently in use.Conclusion:The grading system for necrosis of pedicled flap in reconstruction of foot and ankle proposed in this study is simple and clear. It is able to effectively guide the treatment of flap necrosis. The preliminary validation shows that the classification system has good repeatability.

【Objective】 To understand the current situation of social emotional competence of infants and toddlers, and analyze its relationship with home rearing environment, in order to provide the basis for improving the level of infant social emotional development. 【Method】 A study was conducted on 390 individuals from a child health institution in Hubei and Henan provinces.The "Infant and Toddler Social-Emotional Assessment Scale" and "1 - 3 Years Child Home Rearing Environment Scale" were used to investigate the social emotions ability and home rearing environment of infants and toddlers. 【Results】 A total of 390 valid questionnaires were collected in this survey, of which 199 were boys (51.0%) and 191 girls (49.0%). The average age of infants was (27.13±6.86)months.The age distribution is mainly among infants and young children aged 24 to 36 months, with a total of 305 people (78.2%). The caregiver′s registered residence (Z=-3.570), father′s education level (H=17.106), mother′s education level (H=7.980), per capita monthly income of the family (H=13.986), and the home rearing environment (Z=-8.881) had statistical significance on the social emotional competence of infants(P<0.05 or <0.01).There was a significant positive correlation between family rearing environment and infants′ social emotion (r=0.582, P<0.01).Multiple regression analysis showed that the social adaptation/self-care(β=0.30, 95%CI: 0.18 - 0.52, P<0.01)and language cognition dimensions(β=0.22, 95%CI: 0.07 - 0.59, P<0.05) in the home rearing environment had a statistically significant impact on the social emotional ability of infants and toddlers. 【Conclusion】 The home rearing environment is closely related to the social emotional development of infants and young children.Improve the parenting knowledge and skills of the main caregivers of infants and young children, build a good family rearing environment for infants and young children, which is beneficial to promote the development of children′s social emotions.