BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

Objective:To investigate the correlation between postoperative spinal sagittal parameters and reinforced vertebral recompression fractures in patients with osteoporotic vertebral compression fractures (OVCFs) who have undergone percutaneous kyphoplasty (PKP).Methods:Data on patients with OVCFs treated with PKP at the Department of Orthopaedics, Second Affiliated Hospital of Soochow University, from August 2020 to August 2024, were collected. Among these, 31 patients who underwent single-segment PKP experienced postoperative reinforced vertebral recompression fractures (recompression fracture group), comprising 8 males and 23 females, with a mean age of 73.74±8.76 years, a body mass index (BMI) of 23.83±1.87 kg/m 2, and a bone mineral density T-value of -2.29±0.55. The remission rate of the visual analogue scale (VAS) after surgery was 80.14%±4.86%, with a mean volume of bone cement used at 5.37±0.69 ml. The surgical segments involved included T 5 (1 case), T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (9 cases), L 1 (7 cases), L 2 (4 cases), L 3 (2 cases), and L 4 (2 cases). Following a 1∶1 matching principle, 31 patients whose vertebrae did not experience reinforced recompression fractures during the same period (non-recompression fracture group) were included. This group also comprised 8 males and 23 females, with a mean age of 74.88±8.31 years, a BMI of 23.15±2.04 kg/m 2, a bone mineral density T-value of -2.76±0.64, and a VAS remission rate of 79.75%±5.01%. The mean volume of bone cement used in this group was 5.41±0.72 ml. The surgical segments involved included T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (8 cases), L 1 (7 cases), L 2 (5 cases), L 3 (2 cases), L 4 (2 cases), and L 5 (1 case). There were no statistically significant differences in the aforementioned indicators between the two patient groups ( P>0.05). A comparison of the postoperative spinal sagittal parameters between the two groups was conducted, focusing on the local kyphosis angle (LKA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and the lumbar-pelvic matching value (PI-LL). Indicators that exhibited statistically significant differences were included in the binary logistic regression analysis to evaluate the impact of spinal sagittal parameters following PKP on the recompression of the reinforced vertebral. Results:The time to reinforced vertebral recompression fractures after PKP ranged from 35 to 184 d, with a median of 69 d. The TK in the recompression fracture group (46.56°±7.02°) was significantly greater than that in the non-recompression fracture group (41.95°±5.76°). Additionally, the LKA, PI and SS were all smaller in the recompression fracture group (9.84°±2.13°, 41.36°±4.27°, 22.69°±5.53°, respectively) compared to the non-recompression fracture group (12.37°±2.64°, 48.09°±6.33°, 28.41°±7.64°), with all differences being statistically significant ( P<0.05). However, no significant differences were observed between the LL, PT, and PI-LL values ( P>0.05). TK, LKA, PI, and SS were included in the binary logistic regression analysis, which indicated that TK [ OR=1.533, 95% CI(1.47, 1.59)] after PKP was positively correlated with the occurrence of reinforced vertebral recompression fractures. Conversely, LKA [ OR=0.882, 95% CI(0.80, 0.96)], PI [ OR=0.815, 95% CI(0.71, 0.91)], and SS [ OR=0.833, 95% CI(0.73, 0.93)] were negatively correlated. Conclusions:The incidence of reinforced vertebral recompression fractures following PKP is associated with spinal sagittal parameters, including TK, LKA, PI, and SS. Specifically, a larger TK and smaller values of LKA, PI, and SS are correlated with an elevated risk of reinforced vertebral recompression fractures.

Objective To investigate the effects of cornuside on intestinal injury in rats with septic shock,and clarify its possible mechanism.Methods SD rats were randomly divided into normal control group,model group,low-,medium-,and high-dose comecarpine glycosides groups,and TREM1 inhibitor(LR12)group.HE staining was used to observe the pathological injury of small intestinal mucosa.The levels of D-lactic acid(D-LA)and diamine oxidase(DAO)in serum and secretory immunoglobulin(sIg A)in small intestine were detected by ELISA.Intestinal mucosal permeability was detected by fluorescein isothiocyanate-dextran(FITC-D)tracer method.ELISA was used to detect the levels of interferon(IFN)-γ,tumor necrosis factor(TNF)-α,interleukin(IL)-1β,IL-10 and arginase(Arg)-1 in serum.The polarization of macrophages in small intestinal tissue was detected by flow cytometry.Western blot was used to detect the protein expression levels of triggering receptor expressed on myeloid cells 1(TREM1),CD86 and CD206 in small intestine.Results Compared with the normal control group,the model group had serious pathological injury of the small intestinal mucosa,and the serum levels of D-LA,DAO,FITC-D,IFN-γ,TNF-α,and IL-1β significantly increased(P<0.05),while the levels of sIg A,IL-10,and Arg-1 significantly decreased(P<0.05).The M1/M2 ratio of macrophages and the expression levels of TREM1 and CD86 proteins in the small intestine tissue significantly increased(P<0.05),while the expression level of CD206 protein significantly decreased(P<0.05).Compared with the model group,the small intestinal mucosal injury of the rats in each dose cornuside group and LR12 group significantly improved,and the serum levels of D-LA,DAO,FITC-D,IFN-γ,TNF-α,and IL-1β significantly decreased(P<0.05),while the levels of sIg A,IL-10,and Arg-1 significantly increased(P<0.05).The M1/M2 ratio of macrophages and the expression levels of TREM1 and CD86 proteins in the small intestine tissue significantly decreased(P<0.05),while the expression level of CD206 protein significantly increased(P<0.05).Conclusion Cornuside can reduce intestinal injury in rats with septic shock,and the mechanism may be related to inhibiting TREM1-mediated M1 polarization of macrophages.

Objective:To investigate the correlation between postoperative spinal sagittal parameters and reinforced vertebral recompression fractures in patients with osteoporotic vertebral compression fractures (OVCFs) who have undergone percutaneous kyphoplasty (PKP).Methods:Data on patients with OVCFs treated with PKP at the Department of Orthopaedics, Second Affiliated Hospital of Soochow University, from August 2020 to August 2024, were collected. Among these, 31 patients who underwent single-segment PKP experienced postoperative reinforced vertebral recompression fractures (recompression fracture group), comprising 8 males and 23 females, with a mean age of 73.74±8.76 years, a body mass index (BMI) of 23.83±1.87 kg/m 2, and a bone mineral density T-value of -2.29±0.55. The remission rate of the visual analogue scale (VAS) after surgery was 80.14%±4.86%, with a mean volume of bone cement used at 5.37±0.69 ml. The surgical segments involved included T 5 (1 case), T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (9 cases), L 1 (7 cases), L 2 (4 cases), L 3 (2 cases), and L 4 (2 cases). Following a 1∶1 matching principle, 31 patients whose vertebrae did not experience reinforced recompression fractures during the same period (non-recompression fracture group) were included. This group also comprised 8 males and 23 females, with a mean age of 74.88±8.31 years, a BMI of 23.15±2.04 kg/m 2, a bone mineral density T-value of -2.76±0.64, and a VAS remission rate of 79.75%±5.01%. The mean volume of bone cement used in this group was 5.41±0.72 ml. The surgical segments involved included T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (8 cases), L 1 (7 cases), L 2 (5 cases), L 3 (2 cases), L 4 (2 cases), and L 5 (1 case). There were no statistically significant differences in the aforementioned indicators between the two patient groups ( P>0.05). A comparison of the postoperative spinal sagittal parameters between the two groups was conducted, focusing on the local kyphosis angle (LKA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and the lumbar-pelvic matching value (PI-LL). Indicators that exhibited statistically significant differences were included in the binary logistic regression analysis to evaluate the impact of spinal sagittal parameters following PKP on the recompression of the reinforced vertebral. Results:The time to reinforced vertebral recompression fractures after PKP ranged from 35 to 184 d, with a median of 69 d. The TK in the recompression fracture group (46.56°±7.02°) was significantly greater than that in the non-recompression fracture group (41.95°±5.76°). Additionally, the LKA, PI and SS were all smaller in the recompression fracture group (9.84°±2.13°, 41.36°±4.27°, 22.69°±5.53°, respectively) compared to the non-recompression fracture group (12.37°±2.64°, 48.09°±6.33°, 28.41°±7.64°), with all differences being statistically significant ( P<0.05). However, no significant differences were observed between the LL, PT, and PI-LL values ( P>0.05). TK, LKA, PI, and SS were included in the binary logistic regression analysis, which indicated that TK [ OR=1.533, 95% CI(1.47, 1.59)] after PKP was positively correlated with the occurrence of reinforced vertebral recompression fractures. Conversely, LKA [ OR=0.882, 95% CI(0.80, 0.96)], PI [ OR=0.815, 95% CI(0.71, 0.91)], and SS [ OR=0.833, 95% CI(0.73, 0.93)] were negatively correlated. Conclusions:The incidence of reinforced vertebral recompression fractures following PKP is associated with spinal sagittal parameters, including TK, LKA, PI, and SS. Specifically, a larger TK and smaller values of LKA, PI, and SS are correlated with an elevated risk of reinforced vertebral recompression fractures.

Objective To investigate the effects of cornuside on intestinal injury in rats with septic shock,and clarify its possible mechanism.Methods SD rats were randomly divided into normal control group,model group,low-,medium-,and high-dose comecarpine glycosides groups,and TREM1 inhibitor(LR12)group.HE staining was used to observe the pathological injury of small intestinal mucosa.The levels of D-lactic acid(D-LA)and diamine oxidase(DAO)in serum and secretory immunoglobulin(sIg A)in small intestine were detected by ELISA.Intestinal mucosal permeability was detected by fluorescein isothiocyanate-dextran(FITC-D)tracer method.ELISA was used to detect the levels of interferon(IFN)-γ,tumor necrosis factor(TNF)-α,interleukin(IL)-1β,IL-10 and arginase(Arg)-1 in serum.The polarization of macrophages in small intestinal tissue was detected by flow cytometry.Western blot was used to detect the protein expression levels of triggering receptor expressed on myeloid cells 1(TREM1),CD86 and CD206 in small intestine.Results Compared with the normal control group,the model group had serious pathological injury of the small intestinal mucosa,and the serum levels of D-LA,DAO,FITC-D,IFN-γ,TNF-α,and IL-1β significantly increased(P<0.05),while the levels of sIg A,IL-10,and Arg-1 significantly decreased(P<0.05).The M1/M2 ratio of macrophages and the expression levels of TREM1 and CD86 proteins in the small intestine tissue significantly increased(P<0.05),while the expression level of CD206 protein significantly decreased(P<0.05).Compared with the model group,the small intestinal mucosal injury of the rats in each dose cornuside group and LR12 group significantly improved,and the serum levels of D-LA,DAO,FITC-D,IFN-γ,TNF-α,and IL-1β significantly decreased(P<0.05),while the levels of sIg A,IL-10,and Arg-1 significantly increased(P<0.05).The M1/M2 ratio of macrophages and the expression levels of TREM1 and CD86 proteins in the small intestine tissue significantly decreased(P<0.05),while the expression level of CD206 protein significantly increased(P<0.05).Conclusion Cornuside can reduce intestinal injury in rats with septic shock,and the mechanism may be related to inhibiting TREM1-mediated M1 polarization of macrophages.

Objective:To compare the antiosteoporosis effect of conventional treatment and conventional treatment combined with Denosumab after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCF).Methods:A retrospective cohort study was conducted to analyze the clinical data of 211 patients with OVCF admitted to the Second Affiliated Hospital of Soochow University from September 2020 to September 2022. All the patients were female, aged 56-90 years [(71.4±8.1)years]. The bone mineral density T-score of the lumbar spine was (-2.6±1.0)SD before operation. Fracture segments included T 1-T 9 in 45 patients, T 10-L 2 in 146, and L 3-L 5 in 69. Of all, 174 patients were treated with single-segment surgery, 25 with two-segment surgery and 12 with surgery involving three or more segments. According to the wishes of the patients, 107 patients were treated with daily oral administration of calcium and active Vitamin D after PKP (conventional treatment group) and 104 patients with Denosumab combined with the conventional treatment after PKP (Denosumab therapy group). The bone mineral density T-scores of the lumbar spine of the two groups were compared before surgery and at the last follow-up. The visual analogue scale (VAS) and Oswestry disability index (ODI) before surgery, at 3 days, 6 months after surgery, and at the last follow-up were evaluated and the refracture rate after surgery was detected. Possible adverse effects after medication during anti-osteoporosis treatment were observed in two the groups. Results:All the patients were followed up for 12-24 months [(13.5±2.0)months]. Before surgery, the bone mineral density T-score of the lumbar spine was (-2.7±1.1)SD in the Denosumab therapy group and (-2.5±0.8)SD in the conventional treatment group ( P>0.05). At the last follow-up, the bone mineral density T-score of the lumbar spine was (-2.1±1.1)SD in the Denosumab therapy group, significantly higher than (-2.5±0.9)SD in the conventional treatment group ( P<0.05). In the Denosumab therapy group, the bone mineral density T-score of the lumbar spine at the last follow-up was significantly increased compared to that before surgery ( P<0.01), while there was no significant difference in the conventional treatment group ( P<0.05). Before surgery and at 3 days after surgery, the VAS scores and ODI values were (8.5±0.9)points, (2.8±0.8)points, 48.7±4.8 and 25.6±4.0 in the Denosumab therapy group, which was not statistically different from those in the conventional treatment group [(8.5±1.3)points and (2.8±0.9)points, 47.9±7.0 and 25.9±3.7] ( P>0.05). At 6 months after surgery and at the last follow-up, the VAS scores and ODI values were (2.2±0.8)points, (1.7±0.8)points, 24.2±3.6 and 23.2±4.1 in the Denosumab therapy group, significantly lower than those of the conventional treatment group [(2.8±0.9)points, (2.8±1.1)points, 26.4±3.2 and 27.3±4.0] ( P<0.01). The VAS scores at each time point after surgery in both groups decreased significantly compared with those before surgery ( P<0.05). The VAS scores continued to decrease after surgery in the Denosumab therapy group ( P<0.05), while no significant difference was found among those at different time points in the conventional treatment group ( P>0.05). The ODI values at each time point after surgery in both groups significantly decreased compared to those before surgery ( P<0.05). The ODI values continued to decrease after surgery in the Denosumab therapy group ( P<0.05), while in the conventional treatment group, no significant difference was found between those at 6 months after surgery and those at 3 days after surgery ( P>0.05) and they were improved at the last follow-up compared with those at 3 days after surgery ( P<0.05). The refracture rate after surgery was 6.7% (7/104) in the Denosumab therapy group, significantly lower than 16.8% (18/107) in the conventional treatment group ( P<0.05). No serious complications were observed during the antiosteoporosis period in either group. Conclusion:Compared with daily oral administration of Calcium and active Vitamin D after PKP, the conventional treatment combined with Denosumab after PKP can effectively increase the bone density, relieve pain continuously, improve functional restoration, and reduce the risk of refracture in OVCF patients.

AIM:To investigate the optimal time of blood collection and the best concentration of Ganlong capsule(GLC)-containing serum for steatohepatitis.METHODS:Sixty C57BL/6J mice were gavaged with GLC at a dose of 90 mg/kg body weight,twice a day for 7 days.Control mice were administered the same volume of 0.9%saline.After 0.5,1,2 and 4 h from the last gavage,blood was collected to prepare GLC-containing serum.The LC-MS/MS was used to detect the inosine content of blank and drug-containing serum at different blood collection times to determine the optimal time.Subsequently,NCTC1469 cells stimulated with palmitic acid(PA)were treated with different concentrations of the GLC-containing serum.Nile Red staining was used to detect lipid droplet formation,and RT-qPCR was employed to as-sess the expression of intracellular fatty acid synthesis(Fabp1,Scd1)and fatty acid β-oxidation gene(Pparα).RE-SULTS:(1)LC-MS/MS detection revealed that the inosine concentration peaked 2 h after the last administration.(2)Nile red staining demonstrated that the GLC-containing serum exerted a dose-dependent decreasing trend of lipid droplets in hepatocytes induced by PA.(3)GLC-containing serum significantly downregulated the mRNA expression levels of lipo-genesis-genes(Fabp1 and Scd1)with a dose-dependent decreasing trend in the PA-induced NCTC1469 cells.The mRNA expression of genes associated with fatty acid β-oxidation(Pparα)were upregulated with a dose-dependent increasing trend.CONCLUSION:The 10%GLC-containing serum collected 2 hours after the last administration in mice has the best therapeutic effect for steatohepatitis.

Objective:To explore the impact of different preoperative fluid supplementation methods (oral multidimensional carbohydrates and conventional fluid supplementation) on early postoperative recovery and pain management in patients undergoing unilateral biportal endoscopic (UBE) spine surgery.Methods:A retrospective cohort study was conducted to analyze the data of 386 patients who underwent UBE lumbar spine surgery under general anesthesia in the two courtyards of Beijing Friendship Hospital Affiliated to Capital Medical University from May 2023 to April 2024. All patients were divided into oral multidimensional carbohydrates ( "Outfast" supplementation, composed mainly of water, sugars, salts, and vitamins) group (referred to as oral "Outfast" group, 189 patients) and conventional fluid supplementation group (197 patients) according to the type of fluid replenishment. Patients in the oral "Outfast" group were given one oral dose in the morning of the first surgery, and another oral infusion before 10∶00 in the morning of the next surgery or afternoon surgery. Patients in the conventional fluid supplementation group received intravenous infusion in the morning of the first surgery, and were given intravenous infusion of glucose and sodium chloride injection in the morning of the next surgery or afternoon surgery. The two groups were compared for the proportion of patients receiving preoperative intravenous fluids on the day of surgery, intraoperative and postoperative fluid volumes, average daily fluid volumes over the first three postoperative days, time to first postoperative ambulation, time to first bowel movement, post-anesthesia care unit (PACU) stay duration, 4-hour and 24-hour postoperative visual analog scale (VAS) pain scores, incidence of anesthesia-related adverse reactions, and incidence of severe gastrointestinal adverse reactions. The measurement data of normal distribution were expressed as mean±standard deviation ( ± s), and t-test was used for inter-group comparison. The measurement data of skewed distribution were expressed as M ( Q1, Q3) and rank sum test was used for inter-group comparison. Count data was presented in terms of examples and percentages, and a chi-square test was used for comparison between two groups. Results:In the oral "Outfast" group, 8 patients (4.2%) received preoperative intravenous fluids on the day of surgery, compared to 136 patients (69.0%) in the conventional fluid supplementation group, showing a significant difference ( P<0.001). The postoperative fluid volumes, average daily fluid volumes over the first three postoperative days, and shorter time to first ambulation in the oral multidimensional carbohydrates group were 700.0(600.0, 1 100.0) mL, 200.0(200.0, 300.0) mL, and 6.0(6.0, 11.0) h, respectively. The conventional fluid supplementation group was 1 100.0(700.0, 1 200.0) mL, 600.0(500.0, 700.0) mL, and 12.0(6.0, 19.0) h, respectively. The oral "Outfast" group was lower than the conventional fluid supplementation group ( P<0.001).There were no significant differences between the two groups in intraoperative fluid volumes, time to first bowel movement, PACU stay duration, 4-hour and 24-hour VAS pain scores, incidence of anesthesia-related adverse reactions, or incidence of severe gastrointestinal adverse reactions ( P>0.05). Conclusions:Preoperative oral multidimensional carbohydrates supplementation effectively reduces the amount of preoperative and postoperative intravenous fluid required, shortens the time to first ambulation. Preoperative oral multidimensional carbohydrates is safe and does not adversely impact gastrointestinal reactions or pain management in the postoperative period.

Objective: To understand characteristics of men who have sex with men (MSM) who applied for HIV antibody self-testing reagents through "AIDS self-testing" column of a WeChat official account named "Dark Blue Public Health Center" in Tianjin City, so as to provide insights into exploring online modes of HIV antibody self-testing for MSM. Methods: Data of MSM who were 18 years old or above, currently lived in Tianjin City, had sex with men in the past six months and applied for HIV antibody self-testing reagents through "AIDS self-testing" column from May 2018 to December 2022 were collected. Demographic characteristics, results return and positive findings were descriptively analyzed. Results: Data of 2 064 MSM were collected, including 1 052 MSM aged 20 to 29 years (50.97%), 1 522 unmarried MSM (73.74%), 545 workers (26.41%), 1 385 MSM with college education or above (67.10%), and 315 MSM without testing for HIV antibody in the past (15.26%). A total of 6 470 self-testing reagents were applied, and 5 942 testing results were returned, with a return rate of 91.84%. There were 33.28% (687/2 064) of the applicants applying for 66.32% (4 291/6 470) reagents multiple times. There were 73 MSM with positive results, accounting for 1.23%. Conclusions The MSM applying for HIV antibody self-testing reagents through "AIDS self-testing" are mainly young and highly educated, including some who have never tested for HIV. However, attention should be paid to duplicate applications and the return rate should be increased.