BACKGROUND:Cell-free therapy is a research hotspot in the field of medical cosmetic anti-aging.It is still unknown for paracellular secretion of human umbilical cord mesenchymal stem cell-derived small extracellular vesicles loaded with the antiaging drug α-ketoglutaric acid to delay skin aging.OBJECTIVE:To investigate the effect of the anti-aging agent α-ketoglutarate engineered human umbilical cord mesenchymal stem cell-derived small extracellular vesicles in a D-galactose-induced model of dermal fibroblast senescence.METHODS:(1)Biological characteristics of primary human umbilical cord mesenchymal stem cells were identified by osteogenic-lipogenic differentiation staining and flow cytometry.(2)The small extracellular vesicles derived from human umbilical cord mesenchymal stem cell were obtained by using differential-ultracentrifugation.α-Ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles were constructed by electroporation,and biologically characterized by transmission electron microscopy and nanoparticle tracking analyzer,while the encapsulation rate was assessed using high-performance liquid chromatography.(3)The effect of α-ketoglutarate on the proliferative capacity of dermal fibroblasts was assessed by CCK-8 and Edu cell proliferation assay kits.(4)The effect of α-ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles on delaying the senescence of dermal fibroblasts was evaluated by reactive oxygen species detection kit,western blot assay,and cellular immunofluorescence.RESULTS AND CONCLUSION:(1)The obtained human umbilical cord mesenchymal stem cell and human umbilical cord mesenchymal stem cell-small extracellular vesicles were biologically compatible.(2)There was no toxic effect on dermal fibroblasts when α-ketoglutarate was used in the concentration range of 0.5-8 mmol/L.(3)D-gal induced senescence in dermal fibroblasts,while α-ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles treatment reduced the level of oxidative stress,DNA damage,and collagen loss,which was further verified that α-ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles could effectively slow down the skin aging process.

BACKGROUND:Cell-free therapy is a research hotspot in the field of medical cosmetic anti-aging.It is still unknown for paracellular secretion of human umbilical cord mesenchymal stem cell-derived small extracellular vesicles loaded with the antiaging drug α-ketoglutaric acid to delay skin aging.OBJECTIVE:To investigate the effect of the anti-aging agent α-ketoglutarate engineered human umbilical cord mesenchymal stem cell-derived small extracellular vesicles in a D-galactose-induced model of dermal fibroblast senescence.METHODS:(1)Biological characteristics of primary human umbilical cord mesenchymal stem cells were identified by osteogenic-lipogenic differentiation staining and flow cytometry.(2)The small extracellular vesicles derived from human umbilical cord mesenchymal stem cell were obtained by using differential-ultracentrifugation.α-Ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles were constructed by electroporation,and biologically characterized by transmission electron microscopy and nanoparticle tracking analyzer,while the encapsulation rate was assessed using high-performance liquid chromatography.(3)The effect of α-ketoglutarate on the proliferative capacity of dermal fibroblasts was assessed by CCK-8 and Edu cell proliferation assay kits.(4)The effect of α-ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles on delaying the senescence of dermal fibroblasts was evaluated by reactive oxygen species detection kit,western blot assay,and cellular immunofluorescence.RESULTS AND CONCLUSION:(1)The obtained human umbilical cord mesenchymal stem cell and human umbilical cord mesenchymal stem cell-small extracellular vesicles were biologically compatible.(2)There was no toxic effect on dermal fibroblasts when α-ketoglutarate was used in the concentration range of 0.5-8 mmol/L.(3)D-gal induced senescence in dermal fibroblasts,while α-ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles treatment reduced the level of oxidative stress,DNA damage,and collagen loss,which was further verified that α-ketoglutarate-engineered human umbilical cord mesenchymal stem cell-small extracellular vesicles could effectively slow down the skin aging process.

Objective:To investigate the efficacy of virtual simulation-guided unilateral locking plate combined with Jail screw technique for double column tibial plateau fractures involving the posterolateral plateau.Methods:A retrospective case series study was conducted to analyze the clinical data of 32 patients with double column tibial plateau fractures involving the posterolateral plateau admitted to Nanjing Drum Tower Hospital Group Suqian Hospital from March 2018 to March 2022, including 20 males and 12 females, aged 37-69 years [(47.5±6.9)years]. According to AO/OTA classification, the fractures were classified as type 41B in 17 patients and type 41C in 15. According to the three-column classification, the fractures were classified as lateral column+posterior column in 17 patients and medial column+posterior column in 15. Virtual simulation technique was used to simulate surgical operation before surgery. After reduction, the patients′ tibial plateau mirror models of the healthy side were used to simulate the implantation of internal fixators on the affected side. The position data of the placed internal fixators were obtained to guide the personalized treatment with unilateral locking plate combined with Jail screw technique. The total number of Jail screws, average number of Jail screws, distribution and accuracy of screw placement, operative duration, intraoperative blood loss, and fracture healing status were recorded. The posterior tibial plateau angle (PTSA), proximal medial tibial angle (MPTA) and Rasmussen anatomical score were compared before operation, at 1, 3, 6, 12 months after operation and at the last follow-up. The Lysholm scores at 6, 12 months after operation and at the last follow-up were used to evaluate the knee function. At the last follow-up, the knee range of motion was measured. Postoperative complications were observed.Results:All the patients were followed up for 28-36 months [(30.7±2.3)months]. The total number of Jail screws inserted was 48, with an average of (1.5±0.5) screws. In the sagittal direction, 1-2 Jail screws were inserted in each patient, with an accuracy rate of 88% (42/48). The operative duration was 78-116 minutes [(98.7±10.5)minutes]. The intraoperative blood loss was 70-120 ml [(96.6±15.6)ml]. All the fractures had healing of stage I, with a healing time of 4-7 months [(5.4±0.9)months]. At 1, 3, 6, 12 months after operation and at last follow-up, the PTSA, MPTA, and Rasmussen anatomical scores were significantly improved when compared with those before operation ( P<0.05), while there was no statistically significant difference between those at various postoperative time points ( P>0.05). The Lysholm knee scores were (83.6±3.9)points, (88.5±3.6)points, and (93.7±2.6)points at 6, 12 months after operation, and at the last follow-up, respectively, which were gradually increased with the passage of the follow-up time ( P<0.05). The range of motion was (121.4±4.6)° in flexion and was 0.0(0.0, 3.0)° in extension at the last follow-up. Two patients had superficial wound infection and 1 had wound dehiscence after operation, which recovered with dressing change or debridement and suturing. No deep infection, vascular injury or nerve damage occurred. Conclusions:The virtual simulation-guided unilateral locking plate combined with Jail screw technique has the advantages of high accuracy of screw placement, shorter operative duration, less intraoperative blood loss, satisfactory fracture reduction, favorable recovery of knee function and range of motion, and fewer postoperative complications in the treatment of double column tibial plateau fractures involving the posterolateral plateau.

Objective To analyze the current situation of quality control and regulation of centralized decoction of Chinese materia medica in Hangzhou through a mixed study combining quantitative research and qualitative research;To provide references for its standardization.Methods A self-designed questionnaire was distributed from July 20,2023 to August 10,2023 in institutions providing centralized decoction services of Chinese materia medica in different regions of Hangzhou.Using the stratified sampling method,the institutional personnel who completed the questionnaire survey were selected as the interviewees,and the semi-structured interview was used to refine the theme according to the Colaizzi seven step method.Results Totally 98 questionnaires were distributed and 96 valid questionnaires were recovered,with a valid recovery rate of 97.96%.There were significant differences in soaking time,concentration degree,and special decoction method such as decocted earlier or later of decoction pieces of Chinese materia medica among different types of institutions(P<0.05).The centralized decoction of Chinese materia medica in Hangzhou mainly involves two themes and seven sub themes:the supervision and management of the whole process of centralized decoction of Chinese materia medica(optimizing distribution of medical resources,strengthening of supervision,demanding guidance of standards),the operation of centralized decoction of Chinese materia medica(soaking time of decoction pieces of Chinese materia medica,the pretreatment operation of"decocted earlier and decocted later",the concentration treatment of Chinese materia medica decoction,and the quality control of Chinese materia medica decoction).Conclusion At present,centralized decoction of Chinese materia medica in Hangzhou still needs to be further standardized.It is recommended to strengthen the construction of shared Chinese materia medica pharmacy in the region,establish and improve the standard system of centralized decoction of Chinese materia medica decoction,and strengthen the construction of digital full chain traceability to improve the service quality and management level of centralized decoction of Chinese materia medica in Hangzhou.

Objective:To investigate the efficacy of virtual simulation-guided unilateral locking plate combined with Jail screw technique for double column tibial plateau fractures involving the posterolateral plateau.Methods:A retrospective case series study was conducted to analyze the clinical data of 32 patients with double column tibial plateau fractures involving the posterolateral plateau admitted to Nanjing Drum Tower Hospital Group Suqian Hospital from March 2018 to March 2022, including 20 males and 12 females, aged 37-69 years [(47.5±6.9)years]. According to AO/OTA classification, the fractures were classified as type 41B in 17 patients and type 41C in 15. According to the three-column classification, the fractures were classified as lateral column+posterior column in 17 patients and medial column+posterior column in 15. Virtual simulation technique was used to simulate surgical operation before surgery. After reduction, the patients′ tibial plateau mirror models of the healthy side were used to simulate the implantation of internal fixators on the affected side. The position data of the placed internal fixators were obtained to guide the personalized treatment with unilateral locking plate combined with Jail screw technique. The total number of Jail screws, average number of Jail screws, distribution and accuracy of screw placement, operative duration, intraoperative blood loss, and fracture healing status were recorded. The posterior tibial plateau angle (PTSA), proximal medial tibial angle (MPTA) and Rasmussen anatomical score were compared before operation, at 1, 3, 6, 12 months after operation and at the last follow-up. The Lysholm scores at 6, 12 months after operation and at the last follow-up were used to evaluate the knee function. At the last follow-up, the knee range of motion was measured. Postoperative complications were observed.Results:All the patients were followed up for 28-36 months [(30.7±2.3)months]. The total number of Jail screws inserted was 48, with an average of (1.5±0.5) screws. In the sagittal direction, 1-2 Jail screws were inserted in each patient, with an accuracy rate of 88% (42/48). The operative duration was 78-116 minutes [(98.7±10.5)minutes]. The intraoperative blood loss was 70-120 ml [(96.6±15.6)ml]. All the fractures had healing of stage I, with a healing time of 4-7 months [(5.4±0.9)months]. At 1, 3, 6, 12 months after operation and at last follow-up, the PTSA, MPTA, and Rasmussen anatomical scores were significantly improved when compared with those before operation ( P<0.05), while there was no statistically significant difference between those at various postoperative time points ( P>0.05). The Lysholm knee scores were (83.6±3.9)points, (88.5±3.6)points, and (93.7±2.6)points at 6, 12 months after operation, and at the last follow-up, respectively, which were gradually increased with the passage of the follow-up time ( P<0.05). The range of motion was (121.4±4.6)° in flexion and was 0.0(0.0, 3.0)° in extension at the last follow-up. Two patients had superficial wound infection and 1 had wound dehiscence after operation, which recovered with dressing change or debridement and suturing. No deep infection, vascular injury or nerve damage occurred. Conclusions:The virtual simulation-guided unilateral locking plate combined with Jail screw technique has the advantages of high accuracy of screw placement, shorter operative duration, less intraoperative blood loss, satisfactory fracture reduction, favorable recovery of knee function and range of motion, and fewer postoperative complications in the treatment of double column tibial plateau fractures involving the posterolateral plateau.

Objective To analyze the current situation of quality control and regulation of centralized decoction of Chinese materia medica in Hangzhou through a mixed study combining quantitative research and qualitative research;To provide references for its standardization.Methods A self-designed questionnaire was distributed from July 20,2023 to August 10,2023 in institutions providing centralized decoction services of Chinese materia medica in different regions of Hangzhou.Using the stratified sampling method,the institutional personnel who completed the questionnaire survey were selected as the interviewees,and the semi-structured interview was used to refine the theme according to the Colaizzi seven step method.Results Totally 98 questionnaires were distributed and 96 valid questionnaires were recovered,with a valid recovery rate of 97.96%.There were significant differences in soaking time,concentration degree,and special decoction method such as decocted earlier or later of decoction pieces of Chinese materia medica among different types of institutions(P<0.05).The centralized decoction of Chinese materia medica in Hangzhou mainly involves two themes and seven sub themes:the supervision and management of the whole process of centralized decoction of Chinese materia medica(optimizing distribution of medical resources,strengthening of supervision,demanding guidance of standards),the operation of centralized decoction of Chinese materia medica(soaking time of decoction pieces of Chinese materia medica,the pretreatment operation of"decocted earlier and decocted later",the concentration treatment of Chinese materia medica decoction,and the quality control of Chinese materia medica decoction).Conclusion At present,centralized decoction of Chinese materia medica in Hangzhou still needs to be further standardized.It is recommended to strengthen the construction of shared Chinese materia medica pharmacy in the region,establish and improve the standard system of centralized decoction of Chinese materia medica decoction,and strengthen the construction of digital full chain traceability to improve the service quality and management level of centralized decoction of Chinese materia medica in Hangzhou.

OBJECTIVES: To estimate postmortem interval (PMI) by analyzing the protein changes in skeletal muscle tissues with the protein chip technology combined with multivariate analysis methods. METHODS: Rats were sacrificed for cervical dislocation and placed at 16 ℃. Water-soluble proteins in skeletal muscles were extracted at 10 time points (0 d, 1 d, 2 d, 3 d, 4 d, 5 d, 6 d, 7 d, 8 d and 9 d) after death. Protein expression profile data with relative molecular mass of 14 000-230 000 were obtained. Principal component analysis (PCA) and orthogonal partial least squares (OPLS) were used for data analysis. Fisher discriminant model and back propagation (BP) neural network model were constructed to classify and preliminarily estimate the PMI. In addition, the protein expression profiles data of human skeletal muscles at different time points after death were collected, and the relationship between them and PMI was analyzed by heat map and cluster analysis. RESULTS: The protein peak of rat skeletal muscle changed with PMI. The result of PCA combined with OPLS discriminant analysis showed statistical significance in groups with different time points (P<0.05) except 6 d, 7 d and 8 d after death. By Fisher discriminant analysis, the accuracy of internal cross-validation was 71.4% and the accuracy of external validation was 66.7%. The BP neural network model classification and preliminary estimation results showed the accuracy of internal cross-validation was 98.2%, and the accuracy of external validation was 95.8%. There was a significant difference in protein expression between 4 d and 25 h after death by the cluster analysis of the human skeletal muscle samples. CONCLUSIONS The protein chip technology can quickly, accurately and repeatedly obtain water-soluble protein expression profiles in rats' and human skeletal muscles with the relative molecular mass of 14 000-230 000 at different time points postmortem. The establishment of multiple PMI estimation models based on multivariate analysis can provide a new idea and method for PMI estimation.
Animals ; Humans ; Rats ; Multivariate Analysis ; Postmortem Changes ; Protein Array Analysis ; Technology

Objective:To explore the efficacy of the proximal tibial lateral locking plate with rafting screws combined with Jail screws in the treatment of collapse fracture of the lateral tibial plateau.Methods:A retrospective case series study was performed on clinical data of 36 patients with collapse fracture of the lateral tibial plateau admitted to Suqian Hospital of Nanjing Drum Tower Hospital Group from January 2016 to January 2020, including 19 males and 17 females, aged 34-68 years [(48.6±5.8)years]. Schatzker classification was type II in 28 patients and type III in 8 patients. All patients were treated using the proximal tibial lateral locking plate with raft screws combined with Jail screws. The operation time, intraoperative blood loss and fracture healing were detected. The distance of articular surface collapse of the tibial plateau, posterior inclination angle (PSA) of the tibial plateau, tibial plateau varus angle (TPVA) and Rasmussen anatomical score were compared before operation and at day 2 and 1 year after operation. The Hospital for Special Surgery (HSS) score was used to evaluate knee function at day 2 and 1 year after operation. Complications were also recorded.Results:All patients were followed up for 12-32 months [(19.5±3.1)months]. The operation time was 56-82 minutes [(68.5±9.1)minutes]. The intraoperative blood loss was 40-100 ml [(75.6±10.2)ml]. The fracture was clinically healed by first-stage, with the healing time of 8 to 15 weeks [(12.5±1.3)weeks]. The distance of articular surface collapse of the tibial plateau was improved from (15.5±4.2)mm before operation to (0.7±0.3)mm at day 2 after operation and (1.0±0.2)mm at 1 year after operation (all P<0.01). The PSA was improved from (21.2±2.1)° before operation to (8.9±0.8)° at day 2 after operation and (9.2±0.6)° at 1 year after operation (all P<0.01). The TPA was improved from (100.2±3.7)° before operation to (88.9±1.8)° at day 2 after operation and (87.2±1.6)° at 1 year after operation (all P<0.05). The Rasmussen anatomical score changed from (7.8±1.8)points before operation to (17.1±0.9)points at day 2 after operation and (16.3±0.7)points at 1 year after operation (all P<0.01). There were no significant difference in the distance of articular surface collapse of the tibial plateau, PSA, TPVA and Rasmussen anatomical score at day 2 and 1 year after operation (all P>0.05). The HSS score was (92.8±3.2)points at 1 year after operation, significantly higher than (74.8±3.5) points at day 2 after operation ( P<0.01). Two patients sustained superficial wound infection after operation, which healed after debridement and dressing change. No deep infection occurred. Conclusion:For patients with collapse fracture of the lateral tibial plateau, the proximal tibial lateral locking plate with rafting screws combined with Jail screws can effectively prevent secondary collapse of the articular surface and obtain satisfactory anatomical reduction, good functional recovery and few postoperative complications.

Objective:To compare the clinical effects of minimally invasive reduction through a bone tunnel combined with Jail screwing and those of posterolateral locking plating in the treatment of simple posterolateral tibial plateau fractures.Methods:A retrospective analysis was conducted of the data of 48 patients who had been operatively treated and completely followed up at Department of Orthopedics, Suqian Hospital of Nanjing Drum Tower Hospital Group for simple posterolateral tibial plateau fractures from October 2016 to October 2020. There were 26 males and 22 females, aged from 35 to 68 years. They were divided into a minimally invasive group (25 cases subjected to minimally invasive reduction through a bone tunnel combined with Jail screwing) and an incision group (23 cases subjected to posterolateral locking plating) according to their surgical methods. The operation time, incision length, intraoperative blood loss, fracture healing time, cumulative fluoroscopy time, hospital stay and posterior inclination angles of the tibial plateau and Hospital for Special Surgery (HSS) knee function scores at 1, 3, 6, 9, and 12 months after operation were compared between the 2 groups. Complications in the 2 groups of patients were recorded.Results:There was no significant difference in the preoperative general data between the 2 groups, showing comparability ( P>0.05). The 48 patients were followed up for 12 to 36 months (average 16.5 months). The minimally invasive group was significantly better than the incision group in operation time [(42.6±9.1) min versus (65.7±11.5) min], incision length [(4.0±0.4) cm versus (15.0±1.5) cm], intraoperative blood loss[(22.6±5.8) mL versus (31.5±8.8) mL], hospital stay [(7.6±1.4) d versus (11.1±2.4) d], and HSS score one month after operation [(84.8±1.9) points versus (72.9±4.1) points], but the cumulative fluoroscopy time in the incision group [(4.1±1.4) s]was significantly less than that in the minimally invasive group [(22.3±4.2) s] ( P<0.05). There were no significant differences in fracture healing time, HSS scores at 3, 6, 9, or 12 months after operation, or posterior inclination angle of the tibial plateau between the 2 groups ( P>0.05). There were no such complications as wound infection, vascular injury, internal fixation failure, nonunion or malunion of fractures in either of the 2 groups. Two cases in the incision group presented with symptoms of common peroneal nerve injury but recovered 3 months after operation. Conclusions:Although both minimally invasive reduction through a bone tunnel combined with Jail screwing and posterolateral locking plating can achieve satisfactory outcomes in the treatment of simple posterolateral tibial plateau fractures, the minimally invasive technique is preferable because it shows the advantages of a smaller incision, less bleeding, shorter operation time, a lower operation risk, quicker postoperative recovery and shorter hospital stay.

A new electrochemical sensor for organophosphate pesticide(methyl-paraoxon)detection based on bifunctional cerium oxide(CeO2)nanozyme is here reported for the first time.Methyl-paraoxon was degraded into p-nitrophenol by using CeO2 with phosphatase mimicking activity.The CeO2 nanozyme-modified electrode was then synthesized to detect p-nitrophenol.Cyclic voltammetry was applied to investigate the electrochemical behavior of the modified electrode,which indicates that the signal enhancement effect may attribute to the coating of CeO2 nanozyme.The current research also studied and discussed the main parameters affecting the analytical signal,including accumulation potential,accumulation time,and pH.Under the optimum conditions,the present method provided a wider linear range from 0.1 to 100 μmol/L for methyl-paraoxon with a detection limit of 0.06 μmol/L.To validate the proof of concept,the electrochemical sensor was then successfully applied for the determination of methyl-paraoxon in three herb samples,i.e.,Coix lacryma-jobi,Adenophora stricta and Semen nelum-binis.Our findings may provide new insights into the application of bifunctional nanozyme in electro-chemical detection of organophosphorus pesticide.