BACKGROUND:A large number of studies have demonstrated that stem cell exosomes play an important role in the repair of bone defects,either directly as carriers for loading other small molecules or surface modifications,or by binding to biomaterials to promote the repair and regeneration of bone tissue.OBJECTIVE:To summarize the osteogenic mechanisms of stem cell exosomes from different sources and their research progress in bone defect repair.METHODS:Chinese search terms"stem cell,exosome,bone,biomaterial,carrier,bioceramic,polymer,metal,hydrogel,engineered exosome"were used to search CNKI.English search terms"stem cell,exosome,bone defect,biomaterial,carrier,bioceramic,ploymer,metal material,hydrogel,engineering exosome"were used to search PubMed database.According to the inclusion and exclusion criteria,77 relevant articles were finally included for summary.RESULTS AND CONCLUSION:Exosomes from stem cells of different origins can promote osteoblast proliferation and differentiation,promote angiogenesis,and regulate osteoclast activity and macrophage phenotype to promote bone formation and bone mineralization.In addition,many achievements of exosomes in the field of bone defect repair were described from two aspects:biomaterial-assisted exosomes and engineered exosomes.However,the current research on stem cell exosomes in bone tissue engineering is still insufficient,and most of these studies are limited to small animal models,while the treatment of bone defects in large animals,including humans,will be more complex,which will also become a major challenge for the treatment of bone defects.This will also be a great challenge in the dissemination of exosome therapy.

BACKGROUND:A large number of studies have demonstrated that stem cell exosomes play an important role in the repair of bone defects,either directly as carriers for loading other small molecules or surface modifications,or by binding to biomaterials to promote the repair and regeneration of bone tissue.OBJECTIVE:To summarize the osteogenic mechanisms of stem cell exosomes from different sources and their research progress in bone defect repair.METHODS:Chinese search terms"stem cell,exosome,bone,biomaterial,carrier,bioceramic,polymer,metal,hydrogel,engineered exosome"were used to search CNKI.English search terms"stem cell,exosome,bone defect,biomaterial,carrier,bioceramic,ploymer,metal material,hydrogel,engineering exosome"were used to search PubMed database.According to the inclusion and exclusion criteria,77 relevant articles were finally included for summary.RESULTS AND CONCLUSION:Exosomes from stem cells of different origins can promote osteoblast proliferation and differentiation,promote angiogenesis,and regulate osteoclast activity and macrophage phenotype to promote bone formation and bone mineralization.In addition,many achievements of exosomes in the field of bone defect repair were described from two aspects:biomaterial-assisted exosomes and engineered exosomes.However,the current research on stem cell exosomes in bone tissue engineering is still insufficient,and most of these studies are limited to small animal models,while the treatment of bone defects in large animals,including humans,will be more complex,which will also become a major challenge for the treatment of bone defects.This will also be a great challenge in the dissemination of exosome therapy.

AIM:To clarify the expression characteristics and regulatory role of the long non-coding RNA(lncRNA)metastasis-associated lung adenocarcinoma transcript 1(MALAT1)in oxidative stress and apoptosis of H2O2-induced human lens epithelial cell line HLE-B3.METHODS: HLE-B3 cells were divided into Control group and H2O2 group(cultured with 200 μmol/L H2O2 for 24 h). Levels of reactive oxygen species(ROS)and cell apoptosis rates were detected by flow cytometry. Activities of superoxide dismutase(SOD)and catalase(CAT)were measured using kits, MALAT1 expression was quantified by real-time quantitative PCR, and its cellular localization was determined by fluorescence in situ hybridization. After selecting the Si-MALAT1 sequence with the highest silencing efficiency, the groups were established as Control, H2O2, H2O2+Si-NC, and H2O2+Si-MALAT1. Immunofluorescence staining was employed to detect the apoptosis marker TUNEL and Nrf2 nuclear translocation. RESULTS:Compared with the Control group, the H2O2group exhibited significantly elevated ROS levels, markedly decreased SOD and CAT activities(both P<0.001), and a significantly increased apoptosis rate(P<0.01). MALAT1 expression was upregulated(P<0.01)and localized in the nucleus. After silencing MALAT1, H2O2-induced cell apoptosis was significantly inhibited(P<0.01).CONCLUSION: H2O2-induced oxidative stress can increase the expression of MALAT1, and silencing MALAT1 reduces oxidative stress damage and apoptosis, providing a potential target for preventing and treating cataracts.

AIM: To design and construct recombinant epitope nucleotides vaccine of glycoprotein B(gB)and glycoprotein D(gD)of herpes simplex virus type 1(HSV-1), and to investigate its immunoprotective effects and tissue expression in animal models.METHODS: The HSV-1 gB and gD epitope genes were selected and tandem assembled to construct the recombinant protein-coding gene X, which was transducted into the prokaryotic expression vector pET28(a). The recombinant protein was synthesized and utilized to generate monoclonal antibodies, which were subsequently used to immunize New Zealand white rabbits. The immunogenicity of the purified protein and the presence of polyclonal antibodies in the serum were tested through separating serum from cardiac blood, and the serum antibody titers were determined. The pcDNA3.1-X was successfully constructed as a eukaryotic expression vector and immunized the female BALB/c mice aged 4 to 6 wk via intramuscular injection. Serum antibodies and immune-related cytokines were quantified using enzyme-linked immunosorbent assay(ELISA). The expression of the X protein in the ocular, trigeminal ganglion, and brain tissues of the mice was assessed.RESULTS: The target polyclonal antibody was identified with a serum antibody titer of 1:3200 in the rabbit serum after immunized by recombinant protein X. Upon immunizing mice with the eukaryotic recombinant plasmid pcDNA3.1-X, the concentration of HSV-1 serum IgM antibodies of the experimental group was 12.13±0.85 ng/L, which was significantly higher than that of the vector control group(0.49±0.44 ng/L; t=21.07, P<0.001). The concentrations of cytokines interleukin IL-2, IL-4, IL-10, and IFN-γ in the experimental group were 11.63±0.60, 22.65±1.47, 85.75±14.12, and 114.90±6.39 ng/L, respectively, all of which were significantly higher than those in the vector control group and the blank control group(all P<0.05). Immunohistochemical staining revealed the presence of target protein X in the eyeball, trigeminal ganglion, and brain tissue.CONCLUSION: The HSV-1 gB and gD tandem epitope nucleotides vaccine pcDNA3.1-X was successfully constructed, which activates a remarkable immune response and is stably expressed in the eyeball, trigeminal ganglion, and brain tissue. This study provides a foundation for further research of an HSV-1 recombinant antigen epitope tandem vaccine.

Objective To analyze the nonlinear relationship between hypothermic machine perfusion (HMP) parameters and delayed graft function (DGF) and optimize the construction of a predictive model for DGF. Methods The data of 923 recipients who underwent kidney transplantation from deceased donors were retrospectively analyzed. According to the occurrence of DGF, the recipients were divided into DGF group (n=823) and non-DGF group (n=100). Donor data, HMP parameters and recipient data were analyzed for both groups. The nonlinear relationship between HMP parameters and the occurrence of DGF was explored based on restricted cubic splines (RCS). Over-sampling, under-sampling and balanced sampling were used to address the imbalance in the proportion of DGF to construct logistic regression predictive models. The area under the curve (AUC) of each model was compared in the validation set, and a nomogram model was constructed. Results Donor BMI, cold ischemia time of the donor kidney, and HMP parameters (initial and final pressures, resistance, and perfusion time) were significantly different between the DGF and non-DGF groups (all P<0.05). The RCS analysis revealed a threshold-like nonlinear relationship between HMP parameters and the risk of DGF. Among the models constructed using different sampling methods, the balanced sampling model had the highest AUC. Using this model, a nomogram was constructed to stratify recipients based on risk scores. Recipients in the high-risk group had higher serum creatinine levels at 1, 6, and 12 months after kidney transplantation compared to those in the low-risk group (all P<0.05). Conclusions There is a nonlinear relationship between HMP parameters and the risk of DGF, and the threshold is helpful for organ quality assessment and monitoring of graft function after transplantation. The predictive model for DGF constructed on the base of balanced sampling algorithms helps perioperative decision-making and postoperative graft function monitoring of kidney transplantation.

Poly(ADP-ribosyl)ation (PARylation) is a specific form of post-translational modification (PTM) predominantly triggered by the activation of poly-ADP-ribose polymerase 1 (PARP1). However, the role and mechanism of PARylation in the advancement of acute kidney injury (AKI) remain undetermined. Here, we demonstrated the significant upregulation of PARP1 and its associated PARylation in murine models of AKI, consistent with renal biopsy findings in patients with AKI. This elevation in PARP1 expression might be attributed to trimethylation of histone H3 lysine 4 (H3K4me3). Furthermore, a reduction in PARylation levels mitigated renal dysfunction in the AKI mouse models. Mechanistically, liquid chromatography-mass spectrometry indicated that PARylation mainly occurred in receptor for activated C kinase 1 (RACK1), thereby facilitating its subsequent phosphorylation. Moreover, the phosphorylation of RACK1 enhanced its dimerization and accelerated the ubiquitination-mediated hypoxia inducible factor-1α (HIF-1α) degradation, thereby exacerbating kidney injury. Additionally, we identified a PARP1 proteolysis-targeting chimera (PROTAC), A19, as a PARP1 degrader that demonstrated superior protective effects against renal injury compared with PJ34, a previously identified PARP1 inhibitor. Collectively, both genetic and drug-based inhibition of PARylation mitigated kidney injury, indicating that the PARylated RACK1/HIF-1α axis could be a promising therapeutic target for AKI treatment.

Objective To explore the application effect of personalized osteotomy guide plate in high tibial osteotomy for patients with knee osteoarthritis(KOA).Methods A total of 99 patients with KOA who underwent open wedge high tibial osteotomy(OWHTO)in our hospital from January 2022 to January 2023 were selected and randomly divided into a study group(50 cases)and a control group(49 cases)using a random number table method.The control group received traditional medial OWHTO treatment,and the study group received a combination of medial OWHTO and personalized osteotomy guide plate treatment.The indexes of operation and postoperative rehabilitation,serum inflammatory stress factor[C-reactive protein(CRP),tumor necrosis factor-α(TNF-α),cortisol(Cor),adrenocorticotropin(ACTH)],anatomical structure of knee joint[tibial plateau posterior Angle(PTSA),proximal medial tibial Angle(MPT A),hip knee ankle Angle(HKA)],knee function,ACL shape and function,postoperative complications were compared between the two groups.Results The amount of bleeding,the number of intraoperative fluoroscopy,and the postoperative drainage volume in the study group were(138.69±24.03)ml,(4.83±1.07)times,and(228.95±38.72)ml,respectively,which were all less than those in the control group(154.28±27.16)ml,(7.15±1.14)times,and(271.61±42.19)ml.In the study group,the operation time,incision length,and hospitalization time were(40.96±7.28)min,(8.96±0.85)cm,and(10.73±2.05)d,respectively,which were all shorter than those in the control group[(52.31±10.12)min,(9.51±1.03)cm,and(12.16±2.37)d],with statistically significant differences(P＜0.05).The levels of serum CRP,TNF-α,Cor,and ACTH in the study group on the 3rd day after the operation were(31.36±4.68)mg/L,(26.71±3.84)ng/ml,(241.28±27.45)ng/ml,and(18.65±3.01)pmol/L,respectively,which were lower than those in the control group[(35.07±5.16)mg/L,(30.29±4.15)ng/ml,(279.65±30.12)ng/ml,and(21.73±3.28)pmol/L,respectively],and the differences were statistically significant(P＜0.05).The Hospital for Special Surgery(HSS)knee score and Knee Society Score(KSS)of the study group at 12 months after surgery were(81.24±6.85)points and(78.26±6.14)points,respectively,which were higher than those of the control group[(78.08±6.42)points and(75.53±5.82)points,respectively],with statistically significant differences(P＜0.05);at the 12th month after surgery,the width of the ACL body in the study group was(5.68±0.71)mm,which was greater than that in the control group[(5.12±0.64)mm].The amount of anterior tibial displacement was(5.81±0.43)mm,which was smaller than that in the control group(6.19±0.41)mm,and the differences were statistically significant(P＜0.05);the incidence of postoperative complications in the study group was 4.00％,which was lower than that in the control group(18.37％),and the difference was statistically significant(P＜0.05).Conclusion The combined treatment of medial OWHTO and personalized osteotomy guide plate can reduce surgical trauma in patients with KOA,lower the incidence of complications,facilitate patient recovery,while maintaining the morphology and function of the ACL,and improving prognosis.

Objective:To explore the relationship between urinary cadmium levels and thyroid hormone levels in people aged 40-89 years old in selected areas of China.Methods:Based on the "Investigation of the Impact of Soil Quality of Agricultural Land on Human Health in Typical Areas" project from October 2019 to August 2020, a multi-stage stratified random sampling method was used to include 6 588 middle-aged and older adults aged 40-89. Demographic characteristics, dietary frequency and disease status were collected through the questionnaire and physical examination. Urinary cadmium and urinary creatinine were detected by random midstream urine. Fasting venous blood was collected for the detection of Triiodothyronine (T3) and Thyroxine (T4). The linear mixed effects model was used to explore the association of urine cadmium levels with thyroid hormone levels. Its dose-response relationship was explored by using the restricted cubic spline.Results:The age of the subjects was (63.48±12.18) years, with males accounting for 51.28%. The M ( Q 1,Q 3) of urinary cadmium level, T3 and T4 was 2.48 (1.36, 4.42) μg/g·creatinine, (1.96±0.51) nmol/L and (113.75±29.11) nmol/L, respectively. The linear mixed effects model showed that the changes of T3 and T4 were 0.027 (0.009, 0.044) nmol/L and 2.019 (1.084, 2.953) nmol/L for each one-unit increase (natural logarithm transformed) of urinary cadmium. The restricted cubic spline showed that there was a positive nonlinear association between urinary cadmium and T3 as well as T4 (all Pnonlinear<0.05). Conclusion:In selected areas of China, the urinary cadmium level of middle-aged and older adults aged 40-89 years is positively associated with T3 and T4.

Objective:To investigate the efficacy and safety of high-frequency irreversible electroporation (H-FIRE) in treating benign prostatic hyperplasia (BPH).Methods:This randomized controlled open-label multicenter clinical trial enrolled patients from nine medical centers in China between August 2020 and July 2022. Inclusion criteria: age 50–80 years, International Prostate Symptom Score (IPSS) ≥12, maximum urinary flow rate (Q max) >5 ml/min and ≤15 ml/min. Exclusion criteria: prostate malignancy, contraindications to surgery or anesthesia. Patients were randomized 1∶1 into the H-FIRE group (experimental) or the control group (daily oral 0.2 mg tamsulosin hydrochloride sustained-release capsules). Primary outcomes included Q max, IPSS, prostate volume, and International Index of Erectile Function-5 (IIEF-5) scores, measured at baseline, 1 and 3 months post-treatment. Results:A total of 160 cases were included in this study, including 80 cases in the experimental group and 80 cases in the control group, 30 cases in Renji Hospital, 7 cases in Qilu Hospital of Shandong University, 8 cases in Tongji Hospital, 3 cases in Hunan Provincial Hospital, 13 cases in Shanghai Pudong Hospital, 29 cases in Hwa Mei Hospital, 18 cases in Yiyuan County People's Hospital, and 38 cases in Shanghai East Hospital, and 14 cases in Sun Yat-sen Memorial Hospital. At 3 months of post-treatment, Q max in the experimental group increased by a median of 7.50 (3.55, 14.50) ml/s from the baseline value, whereas in the control group it increased by a median of 1.70 (-1.40, 6.00) ml/s, and the difference between the two groups was statistically significant ( P < 0.01, U = 1 083); and at 3 months of post-treatment, IPSS in the experimental group decreased by a median of 12.00 (7.00, 17.00) points in the test group and 6.00 (2.00, 11.00) points in the control group, and the magnitude of improvement in IPSS scores in the test group was significantly higher than that in the control group ( P < 0.01, U = 1 248); at 3 months of post-treatment, the prostate volume decreased by a median of 12.16 (5.69, 18.27) ml in the experimental group and 0 (-3.94, 6.89) ml in the control group, suggesting that H-FIRE significantly reduced prostate gland volume ( P<0.01, U=1 111). The difference in elevated IIEF-5 scores from baseline at 3 months of treatment between the experimental and control groups was not statistically significant[0(-2.00, 1.00) points vs. 0(-2.00, 1.50) points; P=0.54, U=2 338]. There were no serious adverse events in the two groups. Conclusions:H-FIRE could significantly improve both subjective and objective symptoms of BPH with a low risk of severe complications.

The applications of nuclear technology in industries, medicine, and other fields have increased the risk of radiation injury. Although some small-molecule drugs for radiation injury treatment have been applied clinically or are in preclinical research, their therapeutic efficacy is significantly limited by short circulation time and rapid metabolism. Nanomaterials have attracted growing attention with their outstanding bioactivity, chemical stability, tissue compatibility, and targeted delivery capabilities, therefore having the promise of offering the potential solutions to the limitations of current small-molecule drugs. However, their biosafety and clinical efficacy require further investigation. This review summarizes the design strategies and classifications of nanomaterials for radiation injury treatment, analyzes current research progress in their therapeutic applications, and introduces nanomaterial-based approaches for enhancing the elimination of internal radionuclide contamination. Finally, the challenges and future prospects of nanomaterials in radiation injury treatment are discussed. This review aims to provide researchers with a comprehensive understanding of recent advances in nanomaterial-based radiation injury therapeutics, thereby promoting further development in this field.