The repair of bone defects is heavily influenced by the dynamic osteogenic microenvironment. Static scaffolds constructed by traditional 3D printing technology cannot simulate the dynamic nature of the microenvironment during bone defect repair due to the fixed structure, uncontrollable release of active factors, and difficult regeneration of blood vessels, among other factors. Breaking through the limitations of these static scaffolds and realizing the intelligent and dynamic regulation of the osteogenic microenvironment is a key scientific issue in the field of bone tissue engineering. 4D printing technology combines the dynamic responsiveness of bone restoration materials with the concept of intelligent design to regulate the micro and macro structure of scaffolds. This technology provides a new method for bone tissue engineering by responding to endogenous and exogenous stimuli and creating a better osteogenic microenvironment through functionalized design, including drug delivery and antibacterial function. However, this technology currently suffers from challenges related to dynamic response material design, insufficient precision of printing technology, and mismatches between multi-stimulus response systems, metabolic rhythms of bone tissue, and functionalized composite scaffolds. Future research should focus on the development of smart response materials with excellent dynamic responses and bioactivity, the creation of new printing technologies, and the design of personalized and precise bone repair solutions. The aim of this paper is to review the current research status of 4D printing for bone tissue engineering in terms of material types, response mechanisms, and applications to provide a theoretical basis for the development and clinical application of functional bone repair materials in the future.

[摘 要] 目的：探讨乙醛脱氢酶1A1（ALDH1A1）mRNA负载树突状细胞（DC）疫苗体外诱导抗鼻咽癌干细胞免疫反应的能力。方法：体外转录ALDH1A1 mRNA并电转染至人外周血DC，构建ALDH1A1-DC疫苗，转染EGFP mRNA为对照。流式细胞术检测DC表型、淋巴细胞亚群、细胞毒性T 淋巴细胞（CTL）增殖和细胞因子分泌。分选ALDH+和ALDH- C666-1细胞，检测干细胞标志物（CD24、CD133）和干性基因（OCT4、SOX2、Nanog）的表达水平，采用CCK-8法评估ALDH1A1-DC疫苗诱导的特异性免疫杀伤能力。结果：EGFP-DC荧光表达率显著高于未转染DC（P < 0.000 1），ALDH1A1-DC抗原提呈分子HLA-ABC、共刺激分子CD86、CD40和CCR7表达与未转染DC相比显著增强（P = 0.001 3、P = 0.005 9、P = 0.000 4及P = 0.001 9）。与单独淋巴细胞组（T）及空载DC诱导的淋巴细胞组（DC-T）相比，ALDH1A1-DC诱导的CTL比例最高（均P < 0.000 1），分裂指数最高（P = 0.000 2、P = 0.000 3），且CD8+CD69+（P = 0.000 5、P < 0.000 1）和CD8+ IFN-γ+（P = 0.012 6、P = 0.001 9）细胞亚群比例均显著提高。ALDH1A1-DC-T细胞对ALDH+C666-1悬浮细胞球的杀伤效果显著优于ALDH-细胞球（P = 0.001 0），且与其他各组淋巴细胞相比表现出较强的抗ALDH+C666-1悬浮细胞球的免疫效应（P = 0.001 0，P < 0.000 1）。然而，HLA-ABC阻断后其对ALDH+C666-1细胞的特异性杀伤效应显著降低（P < 0.000 1）。结论：mRNA转染DC后可翻译蛋白并促进DC成熟，增强其诱导特异性CTL免疫反应的能力。

Objective: To investigate the status of latent tuberculosis infection（LTBI）among freshmen in middle schools and their willingness of preventive treatment in Yunyan District of Guiyang, so as to provide a reference for the prevention and control of tuberculosis in schools. Methods: The tuberculin skin test (TST) and X-ray scans were used to screen the TB infection of 13 915 freshmen in middle schools in Yunyan District of Guiyang in 2023, and a questionnaire survey on the willingness of accepting tuberculosis preventive treatment was conducted to LTBI patients. The χ 2 test and Fisher exact probability was conducted for the comparison of the rates among the groups. Results: Among the freshmen screened, the detection rate of LTBI was 3.29%. There were statistically significant difference in LTBI rates among freshmen of different genders (boys:2.87%, girls:3.81%), age groups (12-15 years old:3.31%, 16-17 years old:3.92%, 18-20 years old:1.91%), and school stages (junior high school:3.52%, ordinary high school:5.96%, vocational high school:2.29%)（ χ 2=9.59, 13.08, 54.30, P ＜0.01). A total of 356 LTBI freshmen completed questionnaire survey,and 299(83.99%) were willing to accept tuberculosis preventive treatment, but the actual number of LIBI freshman who underwent preventive treatment was zero. Those LTBI who had received Bacille Calmette Guérin(BCG) vaccine(86.97%) was higher in the reporting rates of being willing to accept preventive treatment than that of LTBI who had not received BCG vaccine( 75.79 %),the differences were statistically significant( χ 2=6.48， P <0.05). The main reasons for refusing preventive treatment was worry about adverse drug reactions(80.70%), social acceptance and the support of social institutions were needed most(85.96%). Conclusions The LTBI rate among freshmen in Yunyan District of GuiYang is higher. Although the freshmen with LTBI have a higher willingness to accept preventive treatment, however, no one has undergone preventive treatment. Corresponding measures need to be taken for improving the preventive treatment rate of LIBI freshmen.

Objective:To analyze the epidemiological and clinical features of infectious diseases of the central nervous system (CNS).Methods:A cross-sectional study and analysis were conducted to summarize the epidemiological and clinical characteristics of 9 918 patients with CNS infectious diseases, who were diagnosed and treated at 29 hospitals across China from January 1, 2001 to December 31, 2020. Data collected included demographic data, clinical manifestations, health economic indicators, and prognostic outcomes.Results:Among the 9 918 collected cases of CNS infectious diseases, 5 559 were male (56.0%) and 4 359 were female (44.0%), with an onset age of 38 (25, 53) years. Education level: slightly more junior high school education (2 651 cases, 26.7%), and less elementary school education and below (2 181 cases, 22.0%) were found. Occupational distribution: farmers were found predominant (3 215 cases, 32.4%), followed by workers (1 826 cases, 18.4%) and students (1 633 cases, 16.5%). Clinical manifestations: headache (6 074 cases, 61.2%), fever (5 869 cases, 59.2%) and positive meningeal irritation signs (2 273 cases, 22.9%) were the 3 most common clinical manifestations, followed by nausea and (or) vomiting (2 095 cases, 21.1%), impaired consciousness (2 077 cases, 20.9%), psychiatric symptom (1 866 cases, 18.8%) and epilepsy (1 627 cases, 16.4%), etc., and cranial nerve involvement was found in 669 cases (6.7%). Major pathogens included viruses in 6 814 cases (68.7%), Mycobacterium tuberculosis in 1 677 cases (16.9%), common bacteria in 864 cases (8.7%), fungi in 254 cases (2.6%), spirochetes of syphilis in 183 cases (1.8%), parasites in 121 cases (1.2%), and rickettsiae in 5 cases (0.1%). Urban-rural distribution: slightly more cases were found in the countryside (5 418 cases, 54.6%) than in the towns (4 500 cases, 45.4%). Distribution of onset by season: 2 412 cases (24.3%) fell ill in spring, 2 835 cases (28.6%) in summer, 2 187 cases (22.1%) in fall, and 2 484 cases (25.0%) in winter. Health economics: the duration of hospitalization was 15 (8, 27) days, and the cost of hospitalization was 1.53 (0.91, 3.02)×10 000 yuan. Prognosis: 9 531 cases (96.1%) were cured or improved, and 92 cases (0.9%) died. Conclusions:The pathogens responsible for CNS infectious diseases are predominantly viruses. Although the incidence is slightly higher during the summer months, the overall seasonal pattern is not particularly pronounced. These infections are more commonly observed in young and middle-aged males and present with a diverse range of clinical manifestations, contributing to a significant disease burden.

Objective:To investigate the effects of baicalin on ferroptosis of mouse fibroblasts (Fbs) under high glucose treatment and its mechanism, and to provide a basis for the treatment of diabetic wounds.Methods:The study was an experimental study. Mouse Fbs were collected and divided into control group with conventional culture, high glucose group treated with glucose at final molarity of 30.0 mmol/L, and low baicalin group and high baicalin group pretreated with baicalin at final molarties of 5 and 10 μmol/L respectively and then treated as that in high glucose group. After 48 h of culture, the cell survival rate was detected by the cell counting kit-8, the reactive oxygen species level in cells was detected by the fluorescent probe method, the levels of malondialdehyde, glutathione, and ferrous ion in cells were detected by colorimetry, and the protein expression levels of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) in cells and nuclear factor-erythroid 2-related factor 2 (Nrf2) in cytoplasm and nucleus were detected by Western blotting. Another batch of mouse Fbs were collected and divided into control group, high glucose group, high baicalin group, and high baicalin+ML385 group. The cells in the first three groups were treated as before, the cells in the last group were pretreated with baicalin and ML385 of Nrf2 inhibitor at final molarties of 10 μmol/L and then treated as that in high glucose group. After 48 h of culture, the protein expression levels of SLC7A11 and GPX4 in cells and the protein expression level of Nrf2 in cytoplasm and nucleus were detected as before. Except that the sample number in detecting SLC7A11 and GPX4 was 4, the sample number in detecting other indexes was 3.Results:After 48 h of culture, the cell survival rates in control group, high glucose group, low baicalin group, and high baicalin group were (100.0±10.7)%, (70.0±5.0)%, (80.9±3.2)%, and (91.4±1.9)%, respectively. Compared with those in control group, the cell survival rate, the glutathione level, and SLC7A11 and GPX4 protein expression levels in cells, and nuclear Nrf2 protein expression level were significantly decreased in high glucose group ( P<0.05), and the levels of reactive oxygen species, malondialdehyde, and ferrous ion in cells, and cytoplasmic Nrf2 protein expression level were significantly increased in high glucose group ( P<0.05). Compared with those in high glucose group, the cell survival rate, glutathione level, SLC7A11 and GPX4 protein expression levels in cells, and nuclear Nrf2 protein expression level in low baicalin group and high baicalin group were significantly increased ( P<0.05), the reactive oxygen species and ferrous ion levels in cells, and cytoplasmic Nrf2 protein expression level in low baicalin group and high baicalin group were significantly decreased ( P<0.05), and the malondialdehyde level in cells in high baicalin group was significantly decreased ( P<0.05). Compared with those in low baicalin group, the cell survival rate, glutathione level, SLC7A11 and GPX4 protein expression levels in cells, and nuclear Nrf2 protein expression level in high baicalin group were significantly increased ( P<0.05), and the reactive oxygen species, malondialdehyde, and ferrous ion levels in cells, and cytoplasmic Nrf2 protein expression level in high baicalin group were significantly decreased ( P<0.05). After 48 h of culture, compared with those in control group, the nuclear Nrf2 protein expression level and SLC7A11 and GPX4 protein expression levels in cells were significantly decreased ( P<0.05), and the cytoplasmic Nrf2 protein expression level was significantly increased in high glucose group ( P<0.05); compared with those in high glucose group, the cytoplasmic Nrf2 protein expression level was significantly decreased ( P<0.05), and the nuclear Nrf2 protein expression level and SLC7A11 and GPX4 protein expression levels in cells were significantly increased in high baicalin group ( P<0.05); compared with those in high baicalin group, the cytoplasmic Nrf2 protein expression level was significantly increased ( P<0.05), and the nuclear Nrf2 protein expression level and SLC7A11 and GPX4 protein expression levels in cells were significantly decreased in high baicalin+ML385 group ( P<0.05). Conclusions:Baicalin can inhibit the occurrence of ferroptosis in cells by activating the Nrf2 signaling pathway and up-regulating the expressions of proteins related to SLC7A11/GPX4 axis in Fbs in high glucose treatment, thus increasing the cell survival rate.

Objectives:This study aims to investigate the expression changes of transient receptor potential vanilloid type 1 (TRPV1) channel and inflammatory factors in the peripheral blood of patients with schizophrenia, and to evaluate their potential value for diagnostic prediction.Methods:This cross-sectional study was conducted at Renmin Hospital of Wuhan University from September 2023 to June 2024. A total of 35 patients with schizophrenia (patient group) from the outpatient/inpatient departments and 35 age-and sex-matched healthy individuals (control group) were recruited. Psychiatric symptoms and cognitive function were evaluated using the Positive and Negative Syndrome Scale (PANSS) and the Brief Assessment of Cognition in Schizophrenia (BACS), respectively. The between-group comparisons of the total scores of these two instruments were calculated using independent samples t-tests. Fasting peripheral blood samples were collected from all participants. Plasma and peripheral blood mononuclear cells (PBMCs) were isolated for subsequent analysis. TRPV1 protein expression was quantified by Western blotting, while inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-6 (IL-6), and interleukin-10 (IL-10), were measured using enzyme-linked immunosorbent assay (ELISA). The between-group differences in TRPV1 and inflammatory cytokines were analyzed using the analysis of covariance (ANCOVA), controlling for age and sex. Pearson correlation analysis was employed to examine relationships between continuous variables, controlling for years of education, age, and sex. The diagnostic performance of TRPV1 and inflammatory cytokines for schizophrenia was assessed using receiver operating characteristic (ROC) curve analysis. Results:Significant between-group differences were observed in BACS total and subscale scores ( t=2.57-9.72, all P<0.01). Compared with the control group, the patient group exhibits significantly decreased expression of TRPV1, IL-4, and IL-10 ( t=6.78, 2.75, 2.53, all P<0.01), increased expression of TNF-α, IL-2, and IL-6 ( t=4.08, 2.64, 2.63, all P<0.01), and an increased IL-6/IL-10 ratio ( t=3.18, P<0.01). Correlation analyses revealed that in the patient group, the TRPV1 expression level was negatively correlated with levels of TNF-α and IL-6, and positively correlated with levels of IL-4 and IL-10 ( r=-0.589, -0.234, 0.341, 0.293, all P<0.05). In the patient group, the TRPV1 expression level was negatively correlated with the negative symptom score of PANSS ( r=-0.299, P<0.05), and the IL-6 level was positively correlated with the negative symptom score, the general pathology score, and the total score of PANSS ( r=0.387, 0.356, 0.321, all P<0.05). The TRPV1 level was positively correlated with the total score of BACS in both the control group and the patient group ( r=0.144, 0.828, all P<0.01). The IL-6/IL-10 ratio was positively correlated with the total score of PANSS and negatively correlated with the total score of BACS in the patient group ( r=0.623, -0.333, all P<0.05). The area under the ROC curve for the combination of TRPV1 level and IL-6/IL-10 ratio was 0.98 (95% confidence interval=0.96 to 1.00). Conclusions:Patients with schizophrenia exhibit reduced expression levels of TRPV1 along with an imbalanced inflammatory response. The combined assessment of TRPV1 level and IL-6/IL-10 ratio has demonstrated a high predictive and diagnostic value for schizophrenia.

Objective:To compare the clinical efficacy of TINAVI orthopaedic robot-assisted pedicle screw placement and free-hand pedicle screw placement in the treatment of lumbar spondylolysis in adolescents.Methods:The clinical data of 65 adolescents with lumbar spondylolysis who underwent surgery in Honghui Hospital, Xi′an Jiaotong University from January 2021 to December 2022 were analyzed retrospectively, including 20 males and 45 females with an age of (21.5 ± 4.3) years. The distribution of spondylolysis included 2 cases of L 3, 13 cases of L 4, 50 cases of L 5. According to the Meyerding classification of spondylolisthesis degree, there were 52 cases of grade Ⅰ, 5 cases of grade Ⅱ and 8 cases without spondylolisthesis, all of which were complicated with intractable back pain. All patients were treated with double segmental pedicle screw reduction and autogenous iliac bone graft. According to different screw placement methods, they were divided into TINAVI orthopedic robot-assisted screw placement group (robot group, 32 cases) and free-hand screw placement group (free-hand group, 33 cases). CT was re-examined after operation. The satisfactory rate of pedicle screw placement and cortical penetration rate were calculated according to Neo standard, and the superior articular process invasion rate of screw was calculated by Babu standard. The operation time, intra-operative blood loss, post-operative drainage, hospital stay, satisfactory rate of screw placement, cortical puncture rate and superior articular process invasion rate were compared between the two groups, and the operative complications and bony fusion time of isthmus were recorded. The visual analogue score (VAS) of lumbar pain, the score of Japanese Orthopaedic Association (JOA) and the score of Oswestry dysfunction (ODI) were compared between the two groups before operation, 1 month after operation and 1 year after operation. Results:There was no significant difference in preoperative general data between the two groups ( P>0.05). All patients completed the operation successfully, anatomical reduction was achieved in patients with spondylolisthesis. No serious operative complications such as nerve and vascular injury occurred during surgery. The operation time in the robot group was longer than that in the free-hand group: (82.6 ± 6.8) min vs. (60.5 ± 7.1) min. There was no significant difference in intra-operative blood loss, post-operative drainage and hospital stay between the two groups ( P>0.05). A total of 128 screws were placed in the robot group, and 132 screws were placed in the freehand group. There were significant differences in the satisfaction rate of screw insertion, cortical penetration rate and articular process invasion rate between the two groups: 96.9%(124/128) vs. 90.9%(120/132), 3.1%(4/128) vs. 9.1%(12/132), 2.3%(3/128) vs. 7.6%(10/132) ( P<0.05). One year after surgery, the isthmus of all patients fused well, the reduction was not lost, the intervertebral disc had no degeneration, and the instrumentation was removed. The VAS, JOA score and ODI score of the two groups at 1 month and 1 year after operation were significantly better than those before operation ( P<0.05). The VAS of the robot group was lower than that of the free-hand group at 1 month and 1 year after operation: (1.6 ± 0.8) points vs. (2.7 ± 0.9) points, (0.3 ± 0.1) points vs. (1.5 ± 0.2) points, the difference is statistically significant ( P<0.05). However, there was no significant difference in JOA score and ODI score between the two groups ( P>0.05). Conclusions:TINAVI orthopaedic robot assisted screw placement and free-hand screw placement can both effectively treat lumbar spondylolysis in adolescents. Compared with free-hand screw placement, TINAVI orthopedic robot assisted screw placement can further improve the accuracy and improve patients′ lumbodorsal pain.

Objective:To investigate the efficacy of a decellularized extracellular matrix (dECM)-quaternized chitosan (QCS)-gelatin (Gel) composite scaffold loaded with growth factors in repairing diabetic foot wounds in a rat model.Methods:A dECM-QCS-Gel composite scaffold (referred to as GDQ scaffold) was fabricated using a 3D bioprinter. Forty 8-week-old male Sprague-Dawley (SD) rats were selected to establish a diabetic foot wound model with a diameter of approximately 1 cm. Based on the treatment methods for diabetic foot wounds, the rats were divided into five groups: Control group (no treatment), Exosome group (wound covered with exosome suspension), Exosome+GDQ group (wound covered with GDQ scaffold loaded with exosome suspension), GDQ group (wound covered with GDQ scaffold alone), and Growth factor+GDQ group (wound covered with GDQ scaffold loaded with recombinant human basic fibroblast growth factor suspension). The wound healing rate was measured. Histological analysis was performed by HE staining and Masson staining. ELISA kits were used to determine the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and IL-10 in wound tissues from each group. Protein expression levels of MIP-1 and MIP-2 genes were also assessed.Results:The wound healing rate of the growth factor+GDQ group on the 21st d was 94.89%±1.21%, which was higher than that of the exosome+GDQ group ( P<0.05). With increasing repair time, the expression levels of TNF-α, IL-1β and IL-6 in each group all decreased, while IL-10 increased in all groups ( P<0.05). Among them, the exosome+GDQ group (TNF-α: 46.54±1.26 pg/ml, IL-1β: 225.79±7.29 pg/ml, IL-6: 142.81±4.02 pg/ml and IL-10: 117.36±0.95 pg/ml, P<0.001) and the growth factor+GDQ group (TNF-α : 40.01±1.64 pg/ml, IL-1β: 209.15±2.98 pg/ml, IL-6: 138.50±2.61 pg/ml and IL-10: 127.66±1.23 pg/ml, P<0.05); The levels of TNF-α and IL-1β in the exosome+GDQ group were both lower than those in the exosome+GDQ group ( P<0.05), and IL-10 was higher than that in the exosome+GDQ group ( P<0.05). On the 7th d the control group showed the highest expression levels of MIP-1α and MIP-2. All other groups had lower levels, with the growth factor+GDQ group showing the lowest among them. On the 21st d, the inflammatory protein expression in the growth factor+GDQ group had further decreased and remained lower than in all other experimental groups. Conclusions:The GDQ composite scaffold, when combined with bioactive factors, can synergistically reduce inflammation in diabetic foot wounds and promote wound healing. The scaffold loaded with basic fibroblast growth factor demonstrated superior therapeutic efficacy compared to the scaffold loaded with exosomes.

To summarize the nursing care of a case of thrombotic microangiopathy complicated late pregnancy with intrahepatic cholestasis of pregnancy resulting in fetal demise.Nursing interventions include:to optimize the maternal status,reduce the risk of induction of labor;to assess the cervical conditions,and complete the preparations for childbirth;to ensure the safety of childbirth and prevent and treat postpartum hemorrhage;to standardize blood purification,promote the recovery of renal function;to pay attention to breast conditions and be vigilant against the occurrence of mastitis;to provide grief care for perinatal loss.After careful treatment and care,the patient was discharged after 25 d of hospitalization,and the prognosis was good at 1-month follow-up after discharge.