Objective To explore the possibility of constructing tissue engineered cartilage complex three-dimensional nano-scaffold with collagen type II and hyaluronic acid (HA) by electrospinning. Methods The three-dimensional porous nano-scaffolds were prepared by electrospinning techniques with collagen type II and HA (8 ∶ 1, W ∶ W), which was dissolved in mixed solvent of 3-trifluoroethanol and water (1 ∶ 1, V ∶ V). The morphology were observed by light microscope and scanning electron microscope (SEM). And the porosity, water absorption rate, contact angle, and degradation rate were detected. Chondrocytes were harvested from 1-week-old Japanese white rabbit, which was disgested by 0.25% trypsin 30 minutes and 1% collagenase overlight. The passage 2 chondrocytes were seeded on the nano-scaffold. The cell adhesion and proliferation were evaluated by cell counting kit 8 (CCK-8). The cell-scaffold composites were cultured for 2 weeks in vitro, and the biological morphology and extracelluar matrix (ECM) secretion were observed by histological analysis. Results The optimal electrospinning condition of nano-scaffold was 10% electrospinning solution concentration, 10 cm receiver distance, 5 mL/ h spinning injection speed. The scaffold had uniform diameter and good porosity through the light microscope and SEM. The diameter was 300-600 nm, and the porosity was 89.5% ± 25.0%. The contact angle was (35.6 ± 3.4)°, and the water absorption was 1 120% ± 34% at 24 hours, which indicated excellent hydrophilicity. The degradation rate was 42.24% ± 1.51% at 48 days. CCK-8 results showed that the adhesive rate of cells with scaffold was 169.14% ± 11.26% at 12 hours, and the cell survival rate was 126.03% ± 4.54% at 7 days. The histological and immunohistochemical staining results showed that the chondrocytes could grow well on the scaffold and secreted ECM. And the similar cartilage lacuma structure could be found at 2 weeks after co-culture, which suggested that hyaline cartilage formed. Conclusion The collage type II and HA complex three-dimensional nano-scaffold has good physicochemical properties and excellent biocompatibility, so it can be used as a tissue engineered cartilage scaffold.
Objective To observe and explore the effects of adipose-derived stem cells (ADSCs)-hyaluronic acid (HA) composite on heal ing of wound combined with radiation injury. Methods The ADSCs were harvested from the fat tissue in groin of 10 inbred Sprague Dawley (SD) rats and were isolated and cultured by enzyme digestion. The ADSCs-HA composite wasprepared with ADSCs (5 × 106 cells/mL) at passage 6 and HA (10 mg/mL). Thirty inbred SD rats, 15 males and 15 females, were randomly divided into groups A (n=10), B (n=10), and C (n=10). A 2 cm × 2 cm full-thickness skin defect was made on the rat back before 20 Gy 60Co radiation exposure. One week after debridement, wounds were treated by petrolatum gauze in group A as the control group, by HA (0.4 mL) and petrolatum gauze in group B, and by ADSCs-HA composite (0.4 mL) and petrolatum gauze in group C. The microvessel density (MVD) and the distribution of CD90 positive cells were observed at 1st, 2nd, 3rd, and 4th weeks. Results The wound heal ing was slower, and wound did not heal at 4th week and still filled with granulation tissue in group A; the wound heal ing of group B was faster than that of group A, and the wound did not heal completely with depression in the center at 4th week; the wound healed completely with epidermil izated surface and no obvious depression at 4th week in group C. The histological observation showed that MVD was significantly higher in group C than in groups A and B at the 1st, 2nd, and 3rd weeks (P lt; 0.05), and in group B than in group A at the 3rd week (P lt; 0.05); MVD was significantly higher in groups B and C than in group A (P lt; 0.05), but no significant difference was found between groups B and C (P gt; 0.05) at 4th week. No CD90 positive cell was found in groups A and B; CD 90 positive cells were observed in group C and gradually decreased with time. Conclusion ADSCs-HA composite can accelerate heal ing of wound combined with radiation injury by promoting and controll ing wound angiogenesis.
Objective To evaluate the feasibility of Seprafilm anti-adhesion membrane, a hyaluronic acid (HA) derivative, on prevention of adhesion in acute injured tendon. Methods Eighteen 4-month-old Chinese white rabbits (half males and half females, weighing 2.0-2.5 kg) were made the laceration models of the bilateral second and third toes of hindpaw. According to different treatments, the rabbits were randomly divided into 4 groups (n=18). The second toe of right hindpaw was wrapped with Seprafilm anti-adhesion membrane (group A); the third toe of right hindpaw was wrapped with polylactic acid membrane (group B); the second toe of left hindpaw was coated with sodium hyaluronate gel (group C); and the third toe of left hindpaw did not treated, as control group (group D). The general condition was observed; the range of motion (ROM) of distal interphalangeal joint was measured; the gross observation and histological observation were performed at 1, 2, and 4 weeks, then the degree of adhesion was graded. Results All rabbits survived to the end of the experiment. There was no significant difference in ROM of distal interphalangeal joint between groups A and B at 1, 2, and 4 weeks (P gt; 0.05). ROM of group A was superior to that of groups C and D at 2 and 4 weeks (P lt; 0.05). The gross and histological observations showed the same result in the grading of adhesion. At 1 week, there was no significant difference in the grading of adhesion among 4 groups (P gt; 0.05); at 2 and 4 weeks, the grading of adhesion in group A was similar to that in group B (P gt; 0.05), and the grading of adhesion in group A was significantly slighter than that in groups C and D (P lt; 0.05). Conclusion Seprafilm anti-adhesion membrane composed of HA derivative can prevent tendon adhesion and improve the joint function in acute tendon injury of rabbits.
Objective To compare the effect of decimeter wave with sodium hyaluronate product (SHP) on preventing and treating peritendinous adhesion and promoting tendon heal ing. Methods Totally 96 healthy male white 6-month-old Leghorn chickens weighing (2.24 ± 0.07) kg were randomized into group A ( decimeter wave therapy group, n=32),in which decimeter wave therapy was appl ied 1 to 21 days after operation at a frequency of 915 MHz, a power of 8 W, radiation distance of 10 cm, for 10 minutes once per day; group B (SHP group, n=32), in which 5 mL and 1.2% SHP was appl ied; and group C (control group, n=32), in which injury received no treatment. The III and IV toes of left feet of all chickens were made into tendon injury model. The general condition of animal was observed after operation; gross and histological observations were made 7, 10, 14, 18, 21 and 28 days after operation, and the biomechanical analysis was done 14 and 28 days after operation. Results Operative incision healed well, no infection and death occurred. Peritendinous adhesions in groups A, B were looser, and tendon heal ing was better than that of group C 14 and 28 days after operation. More fibroblasts with active metabol ism and more collagen formation in groups A, B than that in group C. The Pmax of group A was better than that of group B 14 and 28 days after operation (P lt; 0.05); the δmax of group A was better than that of group B 18 and 21 days after operation (P lt; 0.05), and the W0 of group A was better than that of group B 18, 21 and 28 days after operation (P lt; 0.05). There was no significant difference between group A and group B at the other time points. Conclusion Topical decimeter wave therapy and appl ication of SHP after flexor tendon repair can promote intrinsic heal ing, meanwhile they can prevent the adhesion of tendon and reduce extrinsic heal ing. Decimeter wave therapy can improve the qual ities of tendon’s wound heal ing.
Objective To review the recent advances of cross-linking reagent for producing hyaluronic acid(HA) derivative so as to provide more advice for thedevelopment of HA reagent. Methods Recent original articles related to the species, characteristic, cross-linking methodology and mechanism of the cross-linking reagent to producing HA derivative were summarized and systematically analyzed. Results The derivatives after special kinds of reagents modification would remain their own good biocompatibility and change their original rheololgical characterization and obtain relative long organism residence time. Conclusion Development of hyaluronic derivatives may widen their medical application.
OBJECTIVE: To study the effect of basic fibroblast growth factor (bFGF) and hyaluronic acid gel (HAG) combined with freeze-dried bone allograft in repairing segmental bone defect and to explore their mechanism. METHODS: The 15 mm segmental bone/periosteum defects were created on bilateral radius in 50 New Zealand rabbits and were treated with four different kinds of implants on 25 radius respectively (group A: bFGF and HAG combined with freeze-dried bone; group B: bFGF combined with freeze-dried bone; group C: HAG combined with freeze-dried bone; group D: simple freeze-dried bone as a control). The repair of defect was observed radiologically and histologically and were analyzed by radionuclide bone imaging and measurement of calcium contents at different periods. RESULTS: The new bone formation, bone metabolic activity and calcium contents of defects were higher in group A than in group B (P lt; 0.05), and were higher in group B than in groups C and D (P lt; 0.05). There were no significant difference between groups C and D. The bone defects healed in the 8th week in group A, in the 10th week in group B, but did not healed in the 10th week in groups C and D. CONCLUSION: As an osteogenetic factor, bFGF promotes the new bone formation; as a slow-release carrier, HAG enhances the effectiveness of bFGF. The combination of bFGF, HAG and freeze-dried bone allograft can repair the segmental bone defect more effectively.
OBJECTIVE: To observe the effects of hyaluronic acid (HA) and basic fibroblast growth factor (bFGF) on the proliferation of the cells from medial collateral ligament (MCL) and anterior cruciate ligament (ACL) cells. METHODS: The MCL cells and ACL cells of mature New Zealand white rabbit were cultured, while HA, bFGF or HA and bFGF were added to the cell culture media, the cellular proliferation was assayed by MTT method. RESULTS: HA only had no effect on the preoliferation of ACL cells, but had a small stimulatory effect on the proliferation of MCL cells. The addition of 1 ng/ml bFGF enhanced the proliferation of both MCL and ACL cells significantly, and this enhancement was maximal in the concentration of 50 ng/ml. However, the enhancement of proliferation of MCL and ACL cells could be achieved when the combination of HA in concentration of 100 micrograms/ml and bFGF in concentration of 100 ng/ml. CONCLUSION: It is evident that bFGF can enhance the proliferation of the ligament cells. HA can maintain the normal growth of ACL cells with no effect on the proliferation of the cells, while HA has a small stimulatory effect on the proliferation of MCL cells. However, when bFGF is coordinated with HA, more improvement of cellular proliferation can be achieved. HA can be used as a potential carrier for bFGF to enhance the healing of ligamentous tissue injuries.
OBJECTIVE: To review the recent advances of hyaluronic acid and its derivatives in medical application. METHODS: Recent original articles related to hyaluronan derivatives and their medical applications were retrieved extensively. RESULTS: Hyaluronic acid and its derivatives play important roles in visosurgery, arthritis therapy, prevention of adhesion, drug delivery, soft-tissue dilation, and percutaneous embolization. CONCLUSION: Development of hyaluronan derivatives may widen their medical application.
Purpose To study inhibition effects of retinal pigment epithelial (RPE) cells by hyaluronic acid-stimulating activity(HASA)． Methods The cultured human RPE cells added with a series of HASA was measured with cell counting,tetrazolium(MTT)colorimetric assay and tritium labelled thymidine deoxyribosｅ(3H-TdR)incorporation assay.Flow cytometry(FCM)analysis was used to examine RPE cells cycles. Results HASA at concentrations of 12.5～200 mu;g/ml and within 48 hours inhibited RPE cells proliferation with a dose-dependant and time dependant manners.The maximal inhibition rate of RPE cells by HASF was about 48.0%.FCM revealed that the cells in G1 phase increased 7.2% and cells in S phase decreased 9.7%,compared to controls. Conclusion HASA at a certain dose range and period can inhibit RPE cells proliferation. (Chin J Ocul Fundus Dis,1999,15:72-74)
Objective To systematically evaluate the effectiveness of intra-articular hyaluronic acid injection after arthroscopic debridement for knee osteoarthritis (KOA). Methods Databases including The Cochrane Library, SCI, MEDLINE, EMbase, CBM and WanFang Data were searched from inception to 2012, so as to collect randomized controlled trials (RCTs) on intra-articular hyaluronic acid injection after arthroscopic debridement (combined therapy) vs. monotherapy in treating KOA. Two reviewers independently screened literature according to inclusion and exclusion criteria, evaluated quality, and extracted data. Then the meta-analysis was conducted using RevMan5.0 software. Results A total of 7 RCTs involving 526 patients were included. The results of meta-analyses showed that: there was no significant difference in the excellent-good rate between the combined therapy group and the monotherapy groups including either the intra-articular hyaluronic acid injection group (RR=1.40, 95%CI 0.99 to 1.98, P=0.06) or the arthroscopic debridement group (RR=1.09, 95%CI 0.93 to 1.26, P=0.29). But the intra-articular hyaluronic acid injection group was inferior to the combined therapy group in improving Lysholm score, with a significant difference (MD=–14.81, 95%CI –17.55 to –12.08, Plt;0.000 01). Conclusion Arthroscopic debridement combined with intra-articular hyaluronic acid injection for KOA shows no significant difference in the excellent-good rate compared with the monotherapy, but it is superior to the monotherapy of hyaluronic acid injection in improving Lysholm score, so it is believed the combined therapy group is superior to the control groups in therapeutic effects. Due to the limited quantity and quality of the included studies, this conclusion needs to be proved by performing more high quality RCTs