ObjectiveTo construct bone morphogenetic protein 2 (BMP-2) gelatin/chitosan hydrogel sustained-release system, co-implant with induced pluripotent stem cells (iPS) derived mesenchymal stem cells (MSCs) to hydroxyapatite (HA)/zirconium dioxide (ZrO2) bio porous ceramic foam, co-culture in vitro, and to explore the effect of sustained-release system on osteogenic differentiation of iPS-MSCs.MethodsBMP-2 gelatin/chitosan hydrogel microspheres were prepared by water-in-oil solution. Drug encapsulation efficiency, drug loading, and in vitro sustained release rate of the microspheres were tested. HA/ZrO2 bio porous ceramic foam composite iPS-MSCs and BMP-2 gelatin/chitosan hydrogel sustained release system co-culture system was established as experimental group, and cell scaffold complex without BMP-2 composite gelatin/chitosan hydrogel sustained release system as control group. After 3, 7, 10, and 14 days of co-culture in the two groups, ALP secretion of cells was detected; gene expression levels of core binding factor alpha 1 (Cbfa1), collagen type Ⅰ, and Osterix (OSX) were detected by RT-PCR; the expression of collagen type Ⅰ was observed by immunohistochemical staining at 14 days of culture; and cell creep and adhesion were observed by scanning electron microscopy.ResultsBMP-2 gelatin/chitosan hydrogel sustained-release system had better drug encapsulation efficiency and drug loading, and could prolong the activity time of BMP-2. The secretion of ALP and the relative expression of Cbfa1, collagen type Ⅰ, and OSX genes in the experimental group were significantly higher than those in the control group at different time points in the in vitro co-culture system (P<0.05). Immunohistochemical staining showed that the amount of fluorescence in the experimental group was significantly more than that in the control group, i.e. the expression level of collagen type Ⅰ was higher than that in the control group. The cells could be more evenly distributed on the materials, and the cell morphology was good. Scanning electron microscopy showed that the sustained-release system could adhere to cells well.ConclusioniPS-MSCs have the ability of osteogenic differentiation, which is significantly enhanced by BMP-2 gelatin/chitosan hydrogel sustained-release system. The combination of iPS-MSCs and sustained-release system can adhere to the materials well, and the cell activity is better.
Objective To evaluate the primary cl inical effectiveness of Austin metatarsal osteotomy combined with transection of adductor muscle and transverse metatarsal l igament for treating mild or moderate hallux valgus through a single medial incision. Methods Between May 2006 and January 2009, 41 patients (45 feet) with mild or moderate hallux valgus were treated. There were 9 males (10 feet) and 32 females (35 feet) with an average age of 45.3 years (range, 23-71 years). The hallux valgus angle (HVA) was (33.1 ± 1.4)°, and the first and second inter-metatarsal angle was (20.4 ±1.1)°. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score of the affected foot’s function was 47.2 ± 3.7. A longitudinal medial incision was made at the first metatarsophalangeal joint. By the incision, Austin metatarsal osteotomy and lateral soft tissue release (including transection of adductor muscle and the transverse metatarsal l igament) were performed at the same time. Results During operation, 1 case had superficial peroneal nerve branch injury and suture repair was done microsurgically. All incisions healed by first intention postoperatively. All patients were followed up 16-36 months (mean, 26 months). Medial forefoot numbness occurred in 2 feet at 3 days after operation and rel ieved within 6 weeks. The X-ray films showed bone heal ing at osteotomy site within 8 weeks after operation. At last follow-up, the HVA was (10.7 ± 1.7)°, showing significant difference when compared with preoperative value (t=22.32, P=0.00), and the first and second inter-metatarsal angle was (12.1 ± 1.7)°, also showing significant difference when compared with preoperative value (t=21.17, P=0.03). The postoperative AOFAS ankle and hindfoot score of the affected foot’s function was 84.9 ± 4.5, showing significant difference when compared with preoperative score (t=20.75, P=0.01). No foot hallux varus, hallux valgus, or metatarsal necrosis occurred during follow-up. Conclusion The Austin metatarsal osteotomy combined with transection of adductor muscle, transverse metatarsal l igament through a single medial incision can effectively correct the mild or moderate hallux valgus, and avoid the scar and injury of deep peroneal nerve branches by traditional lateral incision.
ObjectiveTo observe effect and safety of interstitial chemotherapy with 5-fluorouracil sustained release agent in radical operation of colorectal cancer. MethodsOne hundred and sixty patients with colorectal cancer from October 2011 to December 2013 were randomly divided into observation group and control group according to an incomplete random method, 78 cases of them were in the observation group and 82 cases of them were in the control group. All the patients were performed radical resection of colorectal cancer. The abdominal cavity and pelvic cavity were washed after surgery. 5-fluorouracil sustained release agent was implanted in the observation group patients for interstitial chemotherapy, the implant site was at the tumor resection area and the mesenteric artery. Routine chemotherapy was performed in these two groups after operation. The postoperative complications were observed. The postoperative local recurrence rate, liver metastasis rate, and 24-month survival rate were recorded. ResultsThe rates of abdominal complications and toxic effects had no significant differences between these two groups (P > 0.05). The rates of 12-month and 24-month local recurrence and the rate of liver metastasis in the observation group were significant lower than those in the control group[1.3% (1/78) versus 8.5% (7/82), x2=8.934, P=0.023; 5.2% (4/78) versus 23.2% (19/82), x2=14.834, P=0.004; 10.3% (8/78) versus 18.3% (15/82), x2=12.034, P=0.016]. The rate of 24-month survival in the observation group was significant higher than that in the control group[94.9% (74/78) versus 84.1% (69/82), x2=11.465, P=0.010]. ConclusionThe good safety of interstitial chemotherapy with 5-fluorouracil sustained release agent could effectively decrease local recurrence rate and liver metastasis rate of colorectal cancer after radical operation and improve survival time of patients.
Objective To investigate effectiveness of transconjunctival lower eyelid blepharoplasty with “super released” orbital fat in correction of lower eyelid pouch protrusion and tear trough and palpebromalar groove depression. Methods A clinical data of 82 patients (164 sides) with lower eyelid pouch protrusion and tear trough and palpebromalar groove depression, who met the selection criteria between September 2021 and May 2022, was retrospectively analyzed. Of the included patients, 3 were males and 79 were females, with an average age of 34.5 years (range, 22-46 years). All patients had varying degrees of eyelid pouch protrusion and tear trough and palpebromalar groove depression. The deformities were graded by the Barton grading system as gradeⅠ in 64 sides, grade Ⅱ in 72 sides, and grade Ⅲ in 28 sides. The orbital fat transpositions were performed through the lower eyelid conjunctival approach. The membrane surrounding the orbital fat was completely released, allowing the orbital fat to fully herniate until the herniated orbital fat did not retract significantly in a resting and relaxed state, which is regarded as the “super released” standard. The released fat strip was spread into the anterior zygomatic space and the anterior maxillary space, and percutaneous fixed to the middle face. The suture that penetrates the skin was externally fixed by adhesive tape pasting without knotted. Results There were 3 sides with chemosis after operation, 1 side with facial skin numbness, 1 side with mild lower eyelid retraction at the early stage after operation, and 5 sides with slight pouch residue. No hematoma, infection, or diplopia occurred. All patients were followed up 4-8 months, with an average of 6.2 months. The eyelid pouch protrusion, tear trough, and palpebromalar groove depression were significantly corrected. At last follow-up, the deformity was graded by Barton grading system as grade 0 in 158 sides and grade Ⅰ in 6 sides, with a significant difference compared to the preoperative score (P<0.001). Patient’s self-evaluation satisfaction reached very satisfied in 67 cases (81.7%), satisfied in 10 cases (12.2%), generally satisfied in 4 cases (4.8%), and dissatisfied in 1 case (1.2%). Conclusion The “super released” orbital fat can effectively prevent the retraction of orbital fat, reduce the probability of residual or recurrence of eyelid pouches, and improve the correction effect.
【Abstract】 Objective To evaluate the surgical management of rigid post-traumatic thoracolumbar kyphosis (RPTK) by simultaneous posterio-anterior circumferential releasing, correction and anterior corpectomy with preserved posterior vertebral wall. Methods Twenty patients with RPTK were treated between October 2004 and October 2010 by posterior releasing, anterior subtotal corpectomy with preserved posterior vertebral wall, correction, strut graft, and short segmental fixation. There were 14 males and 6 females with an average age of 43.2 years (range, 23-63 years). The time between injury and operation was 4 months to 23 years (mean, 1.4 years). The affected locations were T11 in 1 case, T12 in 8 cases, L1 in 10 cases, and L2 in 1 case. The Cobb angle and the intervertebral height of the fractured vertebra body were measured before and after operations. The degrees of low back pain were assessed by Japanese Orthopaedic Association (JOA) scores. Results No incision infection, nerve injury, or cerebral spinal fluid leakage occurred. Seventeen patients were followed up 1-5 years with an average of 2.8 years. The JOA score at last follow-up (26.2 ± 3.9) was significantly improved when compared with the pre-operative score (14.0 ± 5.7) (t=4.536, P=0.001). One patient had aggravation of kyphosis at 3 months postoperatively, who was in stabilized condition after prolonging immobilizated time. The Cobb angle was corrected from (43.2 ± 11.5)° preoperatively to (9.8 ± 5.7)° at last follow-up, showing significant difference (P lt; 0.01). There was significant difference in the intervertebral height of the fractured vertebra body between preoperation and last follow-up (P lt; 0.05). The intervertebral height of fractured vertebra was restored to 87.0% ± 11.2% of adjacent disc height. Conclusion Posterio-anterior circumferential releasing and anterior corpectomy with preserved posterior vertebral wall can achieve satifactory clinical results, not only in pain relieving, kyphosis correction, vertebral height restoration, and spinal stability restoration, but also in the risk reduce of bleeding and spinal cord disturbance.
Since the release rate of protein in hydrogels is directly dependent upon the size of the protein and the hydrogel, how to deliver low molecular weight protein for prolonged periods has always been a problem. In this article, we present a usage of self-assembling peptide (P3) with the RGD epitope on its N terminus. The concentration of the released insulin-like growth factor 1 (IGF-1) was determined by UV-vis spectroscopy and the release kinetics suggested a notable reduction of the IGF-1 release rate. Cell entrapment experiments revealed that IGF-1 delivery by biotinylated nanofibers could promote the proliferation of the mouse chondrogenic ATDC5 cells when compared with cells embedded within nanofibers with untethered IGF-1.
Objective To summarize the research progress of controlled release of angiogenic factors and osteogenic factors in bone tissue engineering. Methods The domestic and abroad literature on the controlled release structure of growth factors during bone regeneration in recent years was extensively reviewed and summarized. Results The sustained-release structure includes direct binding, microsphere-three-dimensional scaffold structure, core-shell structure, layer self-assembly, hydrogel, and gene carrier. A sustained-release system composed of different sustained-release structures combined with different growth factors can promote bone regeneration and angiogenesis. Conclusion Due to its controllability and persistence, the growth factor sustained-release system has become a research hotspot in bone tissue engineering and has broad application prospects.
OBJECTIVE: To investigate protection of biological activity and controlled release of growth factor by means of drug controlled release technique in tissue engineering. METHODS: Using drug controlled release technique that to embed or microcapsulate the biological drug with biodegradable polymer. RESULTS: The aliphatic polylactone could be used as drug carrier for each drug including the biological matter. And the release behavior of the drug could be controlled by adjusting the molecular structure of the carrier and the controlled release method. The successful example, that to realize regeneration of rat’s sciatic nerve with 5, 10, 15 and 20 mm of gap by using polylactide as nerve guide and the embedding growth factor, had been obtained. CONCLUSION: It is possible to realize protection of biological activity and sustained release of growth factor by using aliphatic polylactone as drug carrier.
Objective To study the outcomes of nerve defect repair with the tissue engineered nerve, which is composed of the complex of SCs, 30% ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeable poly (D, L-lacitic acid) (PDLLA) catheters. Methods SCs were cultured and purified from the sciatic nerves of 1-day-old neonatal SD rats. The 1st passage cells were compounded with bFGF-PLGA sustained release microspheres andECM gel, and then were injected into permeable PDLLA catheters with PLGA microfilaments inside. In this way, the tissueengineered nerve was constructed. Sixty SD rats were included. The model of 15-mm sciatic nerve defects was made, and then the rats were randomly divided into 5 groups, with 12 rats in each. In group A, autograft was adopted. In group B, the blank PDLLA catheters with PBS inside were used. In group C, PDLLA catheters, with PLGA microfilaments and 30% ECM gel inside, were used. In group D, PDLLA catheters, with PLGA microfilaments, SCs and 30% ECM gel inside, were used. In group E, the tissue engineered nerve was appl ied. After the operation, observation was made for general conditions of the rats. The sciatic function index (SFI) analysis was performed at 12, 16, 20 and 24 weeks after the operation, respectively. Eelectrophysiological detection and histological observation were performed at 12 and 24 weeks after the operation, respectively. Results All rats survived to the end of the experiment. At 12 and 16 weeks after the operation, group E was significantly different from group B in SFI (P lt; 0.05). At 20 and 24 weeks after the operation, group E was significantly different from groups B and C in SFI (P lt; 0.05). At 12 weeks after the operation, electrophysiological detection showed nerve conduct velocity (NCV) of group E was bigger than that of groups B and C (P lt; 0.05), and compound ampl itude (AMP) as well as action potential area (AREA） of group E were bigger than those of groups B, C and D (P lt; 0.05). At 24 weeks after the operation, NCV, AMP and AREA of group E were bigger than those of groups B and C (Plt; 0.05). At 12 weeks after the operation, histological observation showed the area of regenerated nerves and the number of myel inated fibers in group E were significantly differents from those in groups A, B and C (Plt; 0.05). The density and diameter of myel inated fibers in group E were smaller than those in group A (Plt; 0.05), but bigger than those in groups B, C and D (P lt; 0.05). At 24 weeks after the operation, the area of regenerative nerves in group E is bigger than those in group B (P lt; 0.05); the number of myel inated fibers in group E was significantly different from those in groups A, B, C (P lt; 0.05); and the density and diameter of myel inated fibers in group E were bigger than those in groups B and C (Plt; 0.05). Conclusion The tissue engineered nerve with the complex of SCs, ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeables PDLLA catheters promote nerve regeneration and has similar effect to autograft in repair of nerve defects.
ObjectiveTo investigate the effectiveness of the arthroscopic lateral retinacular release combined with medial patellofemoral ligament (MPFL) reconstruction for patellar dislocation.MethodsBetween January 2016 and March 2017, 28 cases (32 knees) with patellar dislocation were treated by arthroscopic lateral retinacular release and MPFL reconstruction. There were 6 males (6 knees) and 22 females (26 knees) with an average age of 21 years (range, 17-29 years). The disease duration ranged from 2 days to 2 years (mean, 8 months). Apprehension test of all patients were positive. The preoperative Lysholm score was 68.34±12.26. Anteroposterior X-ray film showed the patellar subluxation or dislocation. The Q angle was (17.67±4.21)° and the distance of tibia tuberosity-trochlear groove was less than 20 mm. The femoral attachment of retinacular were fixed by the interference screws (16 knee) or the anchors (16 knee), respectively.ResultsAll incisions healed by first intention. All patients were followed up 6 months. The function of knee joint was significantly improved at 6 months after operation. The Lysholm score was 92.88±6.42 and the Q angle was (12.15±3.68)° at 6 months. There were significant differences in the Lysholm score and the Q angle between pre- and post-operation (t=–3.408, P=0.006; t=–2.317, P=0.004). Apprehension test of all patients were negative. No knee pain, knee weakness, and patellar dislocation occurred during follow-up. There was no significant difference in the Lysholm score and the Q Angle between the anchor group and interference screw group (t=–3.254, P=0.820; t=–3.576, P=0.940). ConclusionLateral retinacular release combined with MPFL reconstruction under arthroscopy can effectively improve the function of the knee joint for patients with Q angle less than 20° and TT-TG less than 20 mm, and the early effectiveness is good. There is no significant difference in knee function between the anchor and interference screw internal fixation.