BACKGROUND:MXene-based hydrogel is a kind of nano-composite multifunctional hydrogel material,which has broad application prospects in the field of chronic wound repair,such as diabetic foot,pressure sore,cancer,and traumatic ulcer.OBJECTIVE:To review the advantages of MXene-based hydrogels and their application and related action mechanism in wound repair.METHODS:The articles included in CNKI,VIP,PubMed,and Science Direct databases were searched from January 2010 to October 2023.The key words were"MXene,hydrogel,tissue engineering application,wound repair"in Chinese and"MXene,hydrogel,wound repair"in English.Finally,70 articles that met the criteria were selected for review.RESUILTS AND CONCLUSION:MXene-based hydrogels have excellent mechanical,electrical,photo-thermal properties,biocompatibility,and antibacterial effects in wound tissue engineering,and can be combined with other organic and inorganic substances to produce greater therapeutic effects in hydrogel.MXene-based hydrogels can be applied to skin wounds in combination with wound monitoring,drug delivery and release,and photothermal therapy.Despite some progresses in the design and preparation of MXene-based hydrogel composites,they are still in the fundamental research stage.There is a lack of clinical validation regarding their effectiveness and safety,but they hold great potential for development and application.

Objective:To explore the efficacy and safety of one-hole split endoscope (OSE) minimally invasive surgery for the treatment of single-segment thoracic ossification of the ligamentum flavum (TOLF).Methods:This retrospective non-randomized controlled study included 41 patients with single-segment TOLF who underwent surgery at Qilu Hospital of Shandong University between July 2019 and July 2023. Patients were divided into two groups: the OSE group (19 cases) treated with one-hole split endoscope minimally invasive surgery and the open group (22 cases) treated with traditional laminectomy and pedicle screw fixation. There were no significant differences between the two groups on gender, age, disease duration, affected segment, presence or absence of dural ossification, and residual cross-sectional vertebral canal area on CT ( P>0.05). Additionally, perioperative surgical time, estimated blood loss (EBL), incision length, hospital stay duration, hospitalization costs and follow-up duration were compared. The Japanese Orthopaedic Association (JOA) score and Oswestry Disability Index (ODI) were compared preoperatively and at the last follow-up. Complications were also recorded. Results:All patients successfully completed the surgery with no significant differences at the last follow-up ( P>0.05). Compared with the open group, the OSE group had a significantly shorter operative time (133.1±16.8 vs. 160.5±22.6 min), lower EBL (91.2±15.0 vs. 192.5±43.8 ml), shorter incision length (2.6±0.5 vs. 7.9±1.9 cm), reduced hospital stay (3.9±0.8 vs. 5.6±0.8 days), and lower hospitalization costs (34,874.9±4,568.6 vs. 53,162.3±9,815.6 yuan) (all P<0.05). AAt the final follow-up, JOA scores (8.5±0.8 vs. 8.6±1.2) and ODI values (16.7%±2.1% vs. 17.7%±4.4%) showed no significant differences between the OSE and open groups ( P>0.05). During the perioperative period and follow-up, complications occurred in 2 patients in the OSE group (1 cerebrospinal fluid leak, 1 poor wound healing) and in 8 patients in the open group (5 cerebrospinal fluid leaks, 1 neurological deterioration, 2 poor wound healing). Conclusion:OSE minimally invasive surgery is an effective treatment for single-segment thoracic ossification of the ligamentum flavum. Compared with open surgery, it provides advantages such as minimal invasiveness and fewer complications.

BACKGROUND:Asperosaponin Ⅵ has good osteogenic effects,but its ability to promote cellular osteogenesis under hypoxia environment is not yet clear.OBJECTIVE:To investigate the effect and potential mechanism of Asperosaponin Ⅵ on osteogenic differentiation of MC3T3-E1 cells under hypoxia environment.METHODS:MC3T3-E1 cells were divided into three groups.Cells in the control group were cultured in a complete medium under normoxic conditions(volume fraction of 21％O2);cells in the hypoxia group were cultured in the complete medium under hypoxia conditions(volume fraction of 0.5％O2);and cells in the Asperosaponin Ⅵ group were cultured in the complete medium containing Asperosaponin Ⅵ under hypoxia conditions(volume fraction of 0.5％oxygen).After 24 hours of culture,cell counting kit-8 method and EdU staining were used to detect cell proliferation activity,TUNEL staining and western blot assay were performed to detect cell apoptosis,and flow cytometry was used to detect intracellular reactive oxygen species levels and cell cycle distribution.Each group of cells was cultured in an osteogenic induction medium containing 1×10-5,1×10-6,and 1×10-7 mol/L Asperosaponin Ⅵ under hypoxia conditions for 7 days.The optimal concentration of Asperosaponin Ⅵ for intervention was identified using alkaline phosphatase staining under optical microscopy.Western blot was used to detect the expression of bone morphogenetic protein 2,osteopontin,and PI3K/AKT signaling axis-related proteins.RESULTS AND CONCLUSION:(1)Compared with the control group,the proliferation ability of MC3T3-E1 cells decreased under hypoxia conditions.1×10-6 mol/L Asperosaponin Ⅵ could significantly improve the cell proliferation ability under hypoxia conditions and reduce cell apoptosis.(2)Compared with the hypoxia group,the Asperosaponin Ⅵ group showed a decrease in intracellular reactive oxygen species and a significant increase in the proportion of cells in the S phase.(3)Compared with the hypoxia group,the cell morphology in the 1×10-6 mol/L Asperosaponin Ⅵ group was elongated,with more protrusions and darker alkaline phosphatase staining.(4)Compared with the hypoxia group,the expression of bone morphogenetic protein 2 and osteopontin increased in the Asperosaponin Ⅵ group,while the expression of p-PI3K and p-AKT proteins decreased.These findings indicate that under hypoxia conditions,Asperosaponin Ⅵcan promote osteogenic differentiation of MC3T3-E1 cells,possibly by regulating the PI3K/AKT pathway.

BACKGROUND:MXene-based hydrogel is a kind of nano-composite multifunctional hydrogel material,which has broad application prospects in the field of chronic wound repair,such as diabetic foot,pressure sore,cancer,and traumatic ulcer.OBJECTIVE:To review the advantages of MXene-based hydrogels and their application and related action mechanism in wound repair.METHODS:The articles included in CNKI,VIP,PubMed,and Science Direct databases were searched from January 2010 to October 2023.The key words were"MXene,hydrogel,tissue engineering application,wound repair"in Chinese and"MXene,hydrogel,wound repair"in English.Finally,70 articles that met the criteria were selected for review.RESUILTS AND CONCLUSION:MXene-based hydrogels have excellent mechanical,electrical,photo-thermal properties,biocompatibility,and antibacterial effects in wound tissue engineering,and can be combined with other organic and inorganic substances to produce greater therapeutic effects in hydrogel.MXene-based hydrogels can be applied to skin wounds in combination with wound monitoring,drug delivery and release,and photothermal therapy.Despite some progresses in the design and preparation of MXene-based hydrogel composites,they are still in the fundamental research stage.There is a lack of clinical validation regarding their effectiveness and safety,but they hold great potential for development and application.

Objective:To explore the efficacy and safety of one-hole split endoscope (OSE) minimally invasive surgery for the treatment of single-segment thoracic ossification of the ligamentum flavum (TOLF).Methods:This retrospective non-randomized controlled study included 41 patients with single-segment TOLF who underwent surgery at Qilu Hospital of Shandong University between July 2019 and July 2023. Patients were divided into two groups: the OSE group (19 cases) treated with one-hole split endoscope minimally invasive surgery and the open group (22 cases) treated with traditional laminectomy and pedicle screw fixation. There were no significant differences between the two groups on gender, age, disease duration, affected segment, presence or absence of dural ossification, and residual cross-sectional vertebral canal area on CT ( P>0.05). Additionally, perioperative surgical time, estimated blood loss (EBL), incision length, hospital stay duration, hospitalization costs and follow-up duration were compared. The Japanese Orthopaedic Association (JOA) score and Oswestry Disability Index (ODI) were compared preoperatively and at the last follow-up. Complications were also recorded. Results:All patients successfully completed the surgery with no significant differences at the last follow-up ( P>0.05). Compared with the open group, the OSE group had a significantly shorter operative time (133.1±16.8 vs. 160.5±22.6 min), lower EBL (91.2±15.0 vs. 192.5±43.8 ml), shorter incision length (2.6±0.5 vs. 7.9±1.9 cm), reduced hospital stay (3.9±0.8 vs. 5.6±0.8 days), and lower hospitalization costs (34,874.9±4,568.6 vs. 53,162.3±9,815.6 yuan) (all P<0.05). AAt the final follow-up, JOA scores (8.5±0.8 vs. 8.6±1.2) and ODI values (16.7%±2.1% vs. 17.7%±4.4%) showed no significant differences between the OSE and open groups ( P>0.05). During the perioperative period and follow-up, complications occurred in 2 patients in the OSE group (1 cerebrospinal fluid leak, 1 poor wound healing) and in 8 patients in the open group (5 cerebrospinal fluid leaks, 1 neurological deterioration, 2 poor wound healing). Conclusion:OSE minimally invasive surgery is an effective treatment for single-segment thoracic ossification of the ligamentum flavum. Compared with open surgery, it provides advantages such as minimal invasiveness and fewer complications.

BACKGROUND:Asperosaponin Ⅵ has good osteogenic effects,but its ability to promote cellular osteogenesis under hypoxia environment is not yet clear.OBJECTIVE:To investigate the effect and potential mechanism of Asperosaponin Ⅵ on osteogenic differentiation of MC3T3-E1 cells under hypoxia environment.METHODS:MC3T3-E1 cells were divided into three groups.Cells in the control group were cultured in a complete medium under normoxic conditions(volume fraction of 21％O2);cells in the hypoxia group were cultured in the complete medium under hypoxia conditions(volume fraction of 0.5％O2);and cells in the Asperosaponin Ⅵ group were cultured in the complete medium containing Asperosaponin Ⅵ under hypoxia conditions(volume fraction of 0.5％oxygen).After 24 hours of culture,cell counting kit-8 method and EdU staining were used to detect cell proliferation activity,TUNEL staining and western blot assay were performed to detect cell apoptosis,and flow cytometry was used to detect intracellular reactive oxygen species levels and cell cycle distribution.Each group of cells was cultured in an osteogenic induction medium containing 1×10-5,1×10-6,and 1×10-7 mol/L Asperosaponin Ⅵ under hypoxia conditions for 7 days.The optimal concentration of Asperosaponin Ⅵ for intervention was identified using alkaline phosphatase staining under optical microscopy.Western blot was used to detect the expression of bone morphogenetic protein 2,osteopontin,and PI3K/AKT signaling axis-related proteins.RESULTS AND CONCLUSION:(1)Compared with the control group,the proliferation ability of MC3T3-E1 cells decreased under hypoxia conditions.1×10-6 mol/L Asperosaponin Ⅵ could significantly improve the cell proliferation ability under hypoxia conditions and reduce cell apoptosis.(2)Compared with the hypoxia group,the Asperosaponin Ⅵ group showed a decrease in intracellular reactive oxygen species and a significant increase in the proportion of cells in the S phase.(3)Compared with the hypoxia group,the cell morphology in the 1×10-6 mol/L Asperosaponin Ⅵ group was elongated,with more protrusions and darker alkaline phosphatase staining.(4)Compared with the hypoxia group,the expression of bone morphogenetic protein 2 and osteopontin increased in the Asperosaponin Ⅵ group,while the expression of p-PI3K and p-AKT proteins decreased.These findings indicate that under hypoxia conditions,Asperosaponin Ⅵcan promote osteogenic differentiation of MC3T3-E1 cells,possibly by regulating the PI3K/AKT pathway.

Objective Establish the method of bacterial endotoxins test for human papillomavirus bivalent(types 16,18)vaccine(pichia pastoris).Methods The method of gel-clot technique and photometric technique(kinetic-turbidimetric assay and kinetic-chromogenic assay)for the determination of bacterial endotoxins was carried out according to the Appendix of China Pharmacopoeia in 2020 Vol Ⅲ 1143"bacterial endotoxins test"and Vol IV 9251"guidelines for bacterial endotoxin test".Results There is no interference after more than forty times dilution for gel-clot technique,the recovery rates of kinetic-turbidimetric assay and kinetic-chromogenic assay can also meet the requirements.Conclusion It is feasible to establish gel-clot technique,kinetic-turbidimetric assay and kinetic-chromogenic assay for bacterial endotoxin test of human papillomavirus bivalent(types 16,18)vaccine(pichia pastoris).

Objective: To examine the impact of laser-assisted hatching (LAH) technique on perinatal outcomes in blastocyst culture of low-grade cleavage embryos, so as to provide insights into improving the utilization of low-grade cleavage embryos and embryo quality. Methods: A total of 369 single live births after transfer of thawed blastocysts following in vitro fertilization or intracytoplasmic sperm injection at Zhejiang Provincial People's Hospital were selected as subjects, and they were divided into 51 conventional culture blastocysts and 318 LAH blastocysts based on whether LAH was performed on day 4 of blastocyst culture. Gestational age, birth weight, birth defects and maternal perinatal information were collected, and the prevalence of premature birth, birth weight and birth defects were analyzed after propensity score matching (PSM). Results: After PSM, 98 matched cases were included in the study. There were no statistically significant differences in maternal age, body mass index, type of infertility and blastocyst age (P>0.05), indicating effective matching. The birth weight of offspring in the LAH group was lower than that in the conventional culture group [(3 261.08±432.24) g vs. (3 464.18±444.46) g; P<0.05]. Conclusion The birth weight of offspring can be reduced by using LAH during blastocyst culture of low-grade cleavage embryos.

Background: Despite strengthened efforts on human immunodeficiency virus (HIV) prevention and control, new HIV infections continue to increase among men who have sex with men (MSM) in China. Pre-exposure prophylaxis (PrEP), a highly effective HIV-prevention tool, has recently been included in China's Action Plan of HIV Prevention and Control. To promote future PrEP implementation, this study aims to identify the barriers and facilitators in PrEP use intention among MSM in China.Methods: In 2018, a cross-sectional survey was conducted among 300 MSM in Nanjing, Jiangsu Province. Questions on demographics, sexual behavior (including a seven-item high-risk behavior index), PrEP use intention, PrEP-related awareness and accessibility, and a seven-item public HIV stigma scale were included in the questionnaire. Bivariate and multivariate logistic regression analyses were conducted to identify factors associated with PrEP use intention. Results: Overall, 44.67％ of the participants had more than two male sexual partners and 5.56％ had HIV-positive sexual partners. Only 57.00％ had heard of PrEP and only four (1.33％) participants had used PrEP. However, 75.34％ expressed the willingness to use oral PrEP if its efficacy was assured. The beliefs that "PrEP can prevent HIV if taken as prescribed" (adjusted odds ratio (AOR) = 4.84, P < 0.001) and "PrEP can be scaled up in the community" (AOR = 3.24, P < 0.001) were positively associated with oral PrEP use intention. Concerns of side effects were negatively associated with oral PrEP use intention (AOR = 0.32, P = 0.006). Further, 77.00％ of the participants would choose injectable or implanted PrEP instead of oral PrEP. One of the PrEP stigma items, "Not certain if doctors can prescribe PrEP if I go to the clinic" was positively associated with the intention to use injectable or implanted PrEP (AOR = 3.03). The items "Heard of PrEP" (AOR = 2.74) and "PrEP can prevent HIV if taken as prescribed" (AOR = 2.65) were also positively related to the intention to use injectable or implanted PrEP. The most common concerns regarding PrEP use were efficacy (44.67％) and side effects (38.67％). The most common reasons for using injectable and implanted PrEP were adherence (81.94％ and 77.86％, respectively) and privacy concerns (56.48％ and 55.00％, respectively). Affordable price and coverage by health insurance were the driving factors for PrEP use. Conclusion: Given the low level of awareness of PrEP-related information in China, it's necessary to provide interventions for high-risk individuals and communities, in order to increase their awareness and knowledge of PrEP. Furthermore, additional alternatives to HIV prevention, such as long-acting injectable or implanted PrEP, should be investigated to reduce the risk of HIV infection in at-risk MSM. Even if this programme could be approved by the National Medical Products Administration of China and implemented, a supportive social environment for MSM is essential during its implementing.