Objective To investigate the influence of diammonium glycyrrhizinate (DG) on the expression of NF-κB and neuron apoptosis after spinal cord ischemia-reperfusion injury in rats. Methods Fourty-eight healthy SD male rats, weighing 220-270 g, were randomly divided into the experimental group and the control group, with 24 rats in each group. A model of spinal cord ischemia-reperfusion injury was completed by intercepting the rats’ abdominal aorta between right and left renal arteries for 30 minunts. In the experimental group, each rat was injected 20 mg/kg DG via subl ingual vein 10 minutes before ischemia occurred. Equal qual ities of physiological sal ine were injected into the rats in the control group. The two groups were observed at 3, 24, 72 and 168 hours after ischemia-reperfusion, respectively. Lumbar myeloid tissues were prepared at the different times, respectively. The expression of NF-κB p65 in lumbar myeloidtissues was analyzed by immunohistochemistry and the apoptosis of neurons was examined by TUNEL reaction. Meanwhile, histological changes of spinal cord were observed by HE staining. Then the correlation between NF-κB and neuron apoptosis was analyzed. Results HE staining showed obvious histological changes of spinal cord of the two groups. In the control group, myeloid tissue edema and normal neurons were observed at 3 hours; there were more histological changes at 24 hours and 72 hours; vacuolus in gray matters and some survived neurons were seen at 168 hours. The histological changes at each time in the experimental group were fewer than those in the control group. The immunohistochemical staining showed that the expression of NF-κB p65 was observed. After ischemia-reperfusion, the expression strengthened at 3 hours, reached the peak at 24 hours and then weakened slowly. At 3, 24, 72 and 168 hours after ischemia-reperfusion, the absorbency (A) value of NF-κB p65 in the experimental group was 0.306 0 ± 0.024 4, 0.396 4 ± 0.022 7, 0.296 6 ± 0.021 1 and 0.267 9 ± 0.015 3, respectively, and that in the control group was 0.361 1 ± 0.017 7, 0.496 6 ± 0.020 1, 0.356 3 ± 0.021 0 and 0.301 4 ± 0.018 1, respectively. There were significant differences between the two groups (P lt; 0.05). The inhabitation ratio of NF- κB p65 expression by DG was 15.40%, 20.17%, 19.28% and 11.11% at 3, 24, 72 and 168 hours after ischemia-reperfusion, respectively. Neuron apoptosis was observed, which strengthened at 3 hours and was the most serious at 24 and 168 hours after ischemia-reperfusion. At 3, 24, 72 and 168 hours after ischemia-reperfusion, the A value of neuron apoptosis in the experimental group was 0.171 0 ± 0.029 1, 0.175 5 ± 0.031 1, 0.175 1 ± 0.027 9 and 0.183 2 ± 0.023 7, respectively, and that in the control group was 0.236 8 ± 0.063 6, 0.241 2 ± 0.042 6, 0.201 5 ± 0.049 8 and 0.250 1 ± 0.048 4, respectively. There were significant differences between the two groups (P lt; 0.05). The inhabitation ratio of neuron apoptosis by DG was 27.79%, 27.23%, 13.08% and 26.74% at 3, 24, 72 and 168 hours after ischemia-reperfusion, respectively. The expression of NF-κB in myeloid tissues was positively correlated with neurons apoptosis in the two groups (r = 0.838, P lt; 0.01). Conclusion Spinal cord ischemia-reperfusion injury may cause a marked expression of NF-κB and notable evidence of neurons apoptosis. DGcan reduce neurons apoptosis by inhibiting the expression of NF-κB.
Objective To investigate the hemostasis of thermosensitive chitosan hemostatic film. Methods Fifty adult Sprague Dawley rats, male or female and weighing 190-210 g, were made the models of liver injury. The models were randomly divided into 5 groups (n=10) depending on different hemostatic materials. The incision of the liver was covered with the hemostatic materials of 2.0 cm × 1.0 cm × 0.5 cm in size: thermosensitive chitosan hemostatic film (group A), chitosan hemostatic film (group B), cellulose hemostatic cotton (group C), gelatin sponge (group D), and no treatment (group E), respectively. The bleeding time and bleeding amount were recorded. After 4 weeks, the incisions of the liver were observed with HE staining. Results Gross observation showed better hemostatic effect and faster hemostatic time in groups A, B, and C; group D had weaker hemostatic effect and slower hemostatic time; group E had no hemostatic effect. The bleeding time and bleeding amount of groups A, B, C, and D were significantly lower than those of group E (P lt; 0.05). The bleeding time and bleeding amount of groups A, B, and C were significantly lower than those of group D (P lt; 0.05), but no significant difference was found among groups A, B, and C (P gt; 0.05). The liver cells of group A had milder edema and ballooning degeneration than other 4 groups through histological observation. Conclusion The thermosensitive chitosan hemostatic film has good hemostasis effect on the liver incision of rats.
Objective To investigate the effects of lycium barbarum polysaccharide (LBP) on the formation of traumatic neuroma and pain after transection of sciatic nerve in rats. Methods Forty Sprague-Dawley (SD) rats, weighing 200-220 g, half male and half female, were allocated into 2 groups randomly: LBP group and control group (n=20 per group). The right sciatic nerves were transected and 2 cm sciatic nerve were removed in all rats of the 2 groups. LBP were intraperitoneally injected in a volum of 10 mg/(kg·d) in the LBP group, while the same volum normal sal ine (NS) in the control group for 28 days. The deficiency of toenail and toe were observed to estimate the autophagy of the operated l imb. Light microscope and transmission electron microscope were used to observe the formation of traumatic neuroma aftertransection of sciatic nerve. Results Autophagy was observed in 5 rats (25%) of LBP group and in 12 rats (60%) of controlgroup at 4 weeks, showing significant difference (P lt; 0.05). Neuroma formed in 8 rats (40%) of LBP group and in 16 rats(80%) of control group, showing significant difference (P lt; 0.05). The observation of l ight microscope showed that there were unorganized growth cells in the neuroma, infiltrated muscle cells, the regeneration of axons and ensheathing cells to form small patch and funicular structure in the control group, while in the LBP group there were less prol iferation of nerve fibers with a regular arrangement. Transmission electron microscope showed that there were lots of axons in nerve tumour, more fusoid fibroblasts, more collagen fiber, and hyperplasia and degenerated myel in sheath in the control group, while in the LBP group there were less myel in sheath in the proximal end of injuring nerves, less Schwann cells and fibroblasts, and sparsed collagen fibers. Conclusion LBP can inhibit autophagy and the formation of traumatic neuroma after transection of sciatic nerve in rats.
Objective To evaluate the effectiveness of open reduction and trans-carpometacarpal joint internal fixation with mini locked-plate for treatment of comminuted fracture of base of the fifth metacarpal. Methods Between July 2015 and December 2017, 8 cases of comminuted fractures of base of the fifth metacarpals were treated with open reduction and trans-carpometacarpal joint internal fixation with mini locked-plate. There were 7 males and 1 female with an age of 19-45 years (mean, 32.5 years). The causes of injury included 2 cases of hitting hard objects while clenching fist, 6 cases of falling injury. There were 2 cases of subluxation of fifth carpal joints and 1 case of dislocation. The time from injury to operation was 1-5 days (mean, 3.5 days). The stability of fracture ends could not be maintained by preoperative evaluation without over articular fixation or short time over articular fixation. Postoperative complications and fracture healing were observed, and hand function was evaluated at last follow-up according to the total active motion (TAM) recommended by the Branch of Hand Surgery of Chinese Medicine Association. Results All the incisions healed by first intention without complications such as wound infection, cutaneous necrosis, tendon or nerve injury. All the patients were followed up 6-18 months (mean, 12 months). All fractures healed with the healing time of 12-16 weeks (mean, 13 weeks). Within 4 months after operation, all patients were able to return to pre-injury job. At last follow-up, according to the TAM recommended by the Branch of Hand Surgery of Chinese Medicine Association, the results were excellent in 7 cases, good in 1 case, with the excellent and good rate of 100%. Conclusion Applying of mini locked-plate for treatment of comminuted fractures of base of the fifth metacarpal, of which cannot obtain stable fixation through non-transarticular or short-time transarticular fixation, can achieve satisfactory functional results with very few complications through trans-carpometacarpal joint approach, thus the procedure can be used as an alternative operation scheme.
ObjectiveTo investigate the effects of exosomes from adipose-derived stem cells (ADSCs) on peripheral nerve regeneration, and to find a new treatment for peripheral nerve injury. MethodsThirty-six adult Sprague Dawley (SD) rats (male or female, weighing 220-240 g) were randomly divided into 3 groups (n=12). Group A was the control group; group B was sciatic nerve injury group; group C was sciatic nerve injury combined with exosomes from ADSCs treatment group. The sciatic nerve was only exposed without injury in group A, and the sciatic nerve crush injury model was prepared in groups B and C. The SD rats in groups A and B were injected with PBS solution of 200 μL via tail veins; the SD rats in group C were injected with pure PBS solution of 200 μL containing 100 μg exosomes from ADSCs, once a week and injected for 12 weeks. At 1 week after the end of the injection, the rats were killed and the sciatic nerves were taken at the part of injury. The sciatic nerve fiber bundles were observed by HE staining; the SCs apoptosis of the sciatic nerve tissue were detected by TUNEL staining; the ultrastructure and SCs autophagy of the sciatic nerve were observed by transmission electron microscope. ResultsGross observation showed that there was no obvious abnormality in the injured limbs of group A, but there were the injured limbs paralysis and muscle atrophy in groups B and C, and the degree of paralysis and muscle atrophy in group C were lighter than those in group B. HE staining showed that the perineurium of group A was regular; the perineurium of group B was irregular, and there were a lot of cell-free structures and tissue fragments in group B; the perineurium of group C was more complete, and significantly well than that of group B. TUNEL staining showed that the SCs apoptosis was significantly increased in groups B and C than in group A, in group B than in group C (P<0.01). Transmission electron microscope observation showed that the SCs autophagosomes in groups B and C were significantly increased than those in group A, but the autophagosomes in group C were significantly lower than those in group B. ConclusionThe exosomes from ADSCs can promote the peripheral nerve regeneration. The mechanism may be related to reducing SCs apoptosis, inhibiting SCs autophagy, and reducing nerve Wallerian degeneration.
Objective To study the effectiveness of TightRope elastic fixation combined with functional total repair of the inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury. Methods The clinical data of 34 patients with distal tibiofibular syndesmosis injury who met the selection criteria between January 2020 and January 2022 were retrospectively analyzed, and they were divided into improved group (TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament) and control group (distal tibiofibular screw fixation) according to the surgical methods, with 17 cases in each group. There was no significant difference in age, gender, body mass index, fracture type, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, and complications were recorded in the two groups. The American Orthopaedic Foot and Ankle Society (AOFAS) score, ankle metatarsal flexion and dorsal extension range of motion were used to evaluate the ankle function. The patient satisfaction survey was conducted at last follow-up. Results All 34 patients were followed up 8-20 months, with a median of 13 months. The operation time and intraoperative blood loss in the improved group were significantly longer than that in the control group (P<0.05). In the improved group, no infection or poor reduction occurred, and only 1 patient had TightRope knot reaction at 6 months after operation. In the control group, there were 2 cases of poor reduction, 1 case of lower tibiofibular screw rupture, and 1 case of subcutaneous infection (cured after anti-infection treatment). There was no significant difference in the incidence of complications between the two groups (P>0.05). At last follow-up, the AOFAS score and ankle metatarsal flexion and dorsal extension range of motion of the improved group were significantly better than those of the control group (P<0.05). The satisfaction rates of patients in the improved group and the control group were 94.1% and 82.4%, respectively, showing significant difference (P<0.05). Conclusion TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury has sufficient fixation strength, and can achieve better effectiveness and joint function compared with traditional screw fixation.
ObjectiveTo compare the effectiveness of subtalar arthroereisis (STA) combined with modified Kidner procedure versus STA alone in the treatment of flexible flatfoot combined with painful accessory navicular bone in children. MethodsThe clinical data of 33 children with flexible flatfoot combined with painful accessory navicular bone who were admitted between August 2018 and August 2021 and met the selection criteria were retrospectively analyzed. They were divided into a combination group (17 cases, treated by STA combined with modified Kidner procedure) and a control group (16 cases, treated by STA alone) according to the surgical methods. There was no significant difference in baseline data between the two groups (P>0.05), such as gender, age, affected side of the foot, disease duration, and preoperative visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, talus-first metatarsal angle (T1MT), talus-second metatarsal angle (T2MT), talonavicular coverage angle (TCA), talus first plantar angle (Meary angle), calcaneal inclination angle (Pitch angle), and heel valgus angle (HV). The operation time, incision length, intraoperative blood loss, number of intraoperative fluoroscopies, and perioperative complications were recorded in both groups. The anteroposterior, lateral, and calcaneal axial X-ray films for the affected feet were taken regularly, and T1MT, T2MT, TCA, Meary angle, Pitch angle, and HV were measured. The VAS score, AOFAS ankle-hindfoot score were used to evaluate pain and functional recovery before and after operation. ResultsSurgeries in both groups were successfully performed without surgical complication such as vascular, nerve, or tendon injuries. Less operation time, shorter incision length, less intraoperative blood loss, and fewer intraoperative fluoroscopies were found in the control group than in the combination group (P<0.05). One case in the combination group had partial necrosis of the skin at the edge of the incision, which healed after the dressing change and infrared light therapy, and the rest of the incisions healed by first intention. All children were followed up 12-36 months, with a mean of 19.6 months. At last follow-up, VAS score and AOFAS ankle-hindfoot score significantly improved in both groups when compared with preoperative ones (P<0.05), and the differences of these scores between before and after operation improved more significantly in the combination group than in the control group (P<0.05). Imaging results showed that the T1MT, T2MT, TCA, Meary angle, and HV significantly improved in both groups at last follow-up when compared with preoperative ones (P<0.05), and the Pitch angle had no significant difference when compared with preoperative one (P>0.05). But there was no significant difference in the difference of these indicators between before and after operation between the two groups (P>0.05).ConclusionBoth procedures are effective in the treatment of flexible flatfoot children with painful accessory navicular bone. STA has the advantage of minimally invasive, while STA combined with modified Kidner procedure has better effectiveness.
Objective To study hemostasis of a new chitosan hemostatic powder. Methods Twenty-four adult SD rats were made the models of l iver injury, male or female, and weighing 210-240 g. They were divided into three groups randomly (n=8) depending on different hemostatic powders. The incision of the l iver was treated with 300 mg Yunnan baiyao (group A1), chitosan hemostatic powder of pH6.5 (group B1) and pH7.5 (group C1), respectively. The bleeding time and bleeding amount were recorded. In vitro, with the modified Ree-White method, 2 mL artery blood from New Zealand whiterabbit was added into the 0.2 mL solution of Yunnan baiyao, chitosan hemostatic powder of pH6.5 and pH7.5 (concentration of 0.2 mg/mL), respectively. The blood coagulation time was recorded. The chitosan blood clots of group B2 and group C2 were observed with scanning electron microscopy (SEM). Results The bleeding time of group A1, group B1 and group C1 was (292 ± 31), (261 ± 23), and (224 ± 28) s, respectively, the bleeding amount was (1.63 ± 0.21), (1.47 ± 0.18), and (1.18 ± 0.17) g, respectively, showing statistically significant differences between groups B1, C1, and group A1 (P lt; 0.05), between group C1 and group B1 (P lt; 0.05). The blood clotting time of group A2, group B2, and group C2 was (653 ± 41), (255 ± 20), and (202 ± 11) s, respectively, showing statistically significant differences between groups B2, C2, and group A2 (P lt; 0.05), between group C2 and group B2 (P lt; 0.05). The SEM showed that the blood cells of group B2 and group C2 gathered around the chitosan. Conclusion Chitosan hemostatic powder of pH7.5 has good hemostasis.
ObjectiveTo study the effect of intraarticular injection of crosslinked-chitosan in the treatment of knee osteoarthritis in rabbits.MethodsThirty-two New Zealand white rabbits were randomly divided into 4 groups (groups A, B, C, and D; 8 rabbits in each group). The knee osteoarthritis models were prepared by anterior cruciate ligament transection in the left hind in groups A, B, and C. At 4 weeks after operation, the rabbits were received intraarticular injection of 0.6 mL crosslinked-chitosan in group A, 0.3 mL chitosan (once per 2 weeks, for twice) in group B, and 0.3 mL saline (once per 2 weeks, for twice) in group C. The rabbits in group D were treated with sham operation in the left hind, and received intraarticular injection of 0.3 mL saline (once per 2 weeks, for twice). At 8 weeks, the macroscopic observation, histological examination (HE staining, Safranin-fast green double staining, and Mankin score), scanning electron microscopy (SEM) observation, and immunohistochemical staining of collagen type Ⅱ were performed.ResultsMacroscopic and SEM observations showed that the cartilage in group D was basically the same as normal and better than that in groups A and B, and the abrasion of cartilage in group C was the most serious. The histological observation results in groups A and B were slightly similar and better than those in group C, but not up to the structure of group D. The macroscopic score and Mankin score of groups B and C were significantly higher than those of group D (P<0.05), and there was no significant difference between group A and group B (P>0.05). Immunohistochemical staining results showed that the collagen type Ⅱ positive percentage of chondrocytes was significantly higher in group D than that in groups B and C, and no significant difference was found between group A and group B (P>0.05). ConclusionThe crosslinked-chitosan can significantly improve the osteoarthritis of the rabbit knee, delay the pathological changes of osteoarthritis, and decrease the frequency of injection.
Objective To measure the concentration of bone morphogenetic protein 2 (BMP-2) in demineralized bone matrix (DBM) prepared from different long bones and to evaluate the osteoinductivity of different DBM on MC3T3-E1 cells. Methods Different bones from the same cadaver donor were used as the initial materials for making DBM, which were divided into ulna group (uDBM), humerus group (hDBM), tibia group (tDBM), and femur group (fDBM) according to the origins, and boiled DBM (cDBM) was taken as the control group. The proteins of DBM were extracted by guanidine hydrochloride, and the concentrations of BMP-2 were determined by ELISA assay. Then the DBM were co-cultured with MC3T3-E1 cells, the proliferation of MC3T3-E1 cells was observed by cell counting kit 8 (CCK-8) assay. The osteogenic differentiation ability of MC3T3-E1 cells was qualitatively observed by alizarin red, alkaline phosphatase (ALP), and Van Gieson staining, and the osteogenic differentiation ability of MC3T3-E1 cells was quantitatively analyzed by ALP content. Linear regression was used to analyze the effect of BMP-2 concentration in DBM on ALP synthesis. ResultsThere were significant differences in the concentration of BMP-2 among the DBM groups (P<0.05). The concentrations of BMP-2 in the lower limb long bone were higher than those in the upper limb long bone, and the concentration of BMP-2 in the fDBM group was about 35.5 times that in the uDBM group. CCK-8 assay showed that the cells in each group continued to proliferate within 5 days of co-culture, and the absorbance (A) values at different time points were in the order of cDBM group<uDBM group<hDBM group<tDBM group<fDBM group. After co-culture for 14 days, the expressions of ALP, calcified nodules, and collagen fibers in each group were consistent with the distribution of BMP-2 concentration in DBM. The order of ALP content from low to high was cDBM group<uDBM group<hDBM group<tDBM group<fDBM group, and the differences between the groups were significant (P<0.05). Linear regression analysis showed that \begin{document}$\hat y $\end{document}=0.361+0.017x, the effect of BMP-2 concentration in DBM on cellular ALP content was significant (t=3.552, P=0.005); for every 1 ng/g increase in BMP-2 concentration, ALP content would increase by 0.017 [95%CI (0.006, 0.027)] U/100 mL. Conclusion The concentration of natural BMP-2 in different long bones varies greatly, and the lower limb long bone is higher than the upper limb long bone. The harvested location of bone material was an important factor affecting the osteoinductivity of DBM.