OBJECTIVE: To summarize the biomechanical research progress of biomaterials in rotator cuff injury repair and to explore how biomaterials can restore the native histological and mechanical properties of the rotator cuff. METHODS: The relevant literature at home and abroad was widely reviewed to analyze the biomechanical properties of synthetic biomaterials, naturally derived biomaterials, and tissue grafts in the repair of rotator cuff injuries. RESULTS: Synthetic biomaterials [such as poly (lactic-co-glycolic acid) and polycaprolactone] can provide initial stable mechanical support due to their adjustable mechanical properties and degradation characteristics, while naturally derived biomaterials (such as collagen and hyaluronic acid) can promote cell adhesion and tissue integration due to their biocompatibility and bioactivity. Tissue grafts exhibit significant clinical utility by providing immediate mechanical stability and promoting tendon-to-bone healing. Three-dimensional bioprinting technology provides new possibilities for personalized repair of rotator cuff injuries by precisely controlling the spatial distribution and mechanical properties of biomaterials. CONCLUSION Future studies should further optimize the design of bioprinting materials, cell sources, and scaffolds to achieve better mechanical properties and clinical efficacy of biomaterials in the repair of rotator cuff injuries.
Humans ; Rotator Cuff Injuries ; Biocompatible Materials/chemistry* ; Biomechanical Phenomena ; Tissue Scaffolds ; Rotator Cuff/surgery* ; Tissue Engineering/methods* ; Polyesters ; Polyglycolic Acid/chemistry* ; Hyaluronic Acid/chemistry* ; Collagen/chemistry* ; Lactic Acid/chemistry* ; Polylactic Acid-Polyglycolic Acid Copolymer ; Bioprinting ; Wound Healing ; Printing, Three-Dimensional ; Tendon Injuries/surgery*

ABSTRACT Various grafting materials are utilised to facilitate regeneration. There is currently a paradigm shift towards applying poly lactic-co-glycolic acid (PLGA), which is regarded as an excellent scaffold for tissue engineering. Concentrated growth factor (CGF) has also been reported to promote wound healing. Nevertheless, the role of PLGA microspheres as a substitute for bone graft material with CGF in bone regeneration remains unclear. This study was designed to evaluate the effect of CGF with PLGA on bone formation and the expression of alkaline phosphatase (ALP) following socket preservation. PLGA microspheres were prepared using double solvent evaporation method and observed under scanning electron microscopy (SEM). A 6 mL of rabbit’s blood was collected from the marginal ear vein and centrifuged to obtain CGF. Blood was also collected for ALP assessment from 24 New Zealand White (NZW) male rabbits subjected to the first upper left premolar extraction. Sockets were filled with CGF, PLGA, CGF+PLGA or left empty and observed with microscopic computed tomography (micro-CT) at four weeks and eight weeks. The SEM image revealed a spherical shape with interconnected pores on the surface of the PLGA particles. Repeated measures ANOVA were used to evaluate the effect of time and treatment (p < 0.05) with significant differences in bone width, height, volume, volume fraction and expression of ALP was observed with CGF+PLGA. Both CGF and PLGA have the potential as the alternative grafting materials and this study could serve as an ideal benchmark for future investigations on the role of CGF+PLGA in bone regeneration enhancement.
Bone Regeneration ; Platelet-Derived Growth Factor ; Polylactic Acid-Polyglycolic Acid Copolymer

OBJECTIVE: To verrify the anti-tumor efficacy and toxicity between juglone (Jug) and Jug-loaded PLGA nanoparticles (Jug-PLGA-NPs). METHODS: Jug-PLGA-NPs were prepared by ultrasonic emulsification. The anti-tumor activity of Jug (2, 3, 4 µg/mL) and Jug-PLGA-NPs (Jug: 2, 3, 4 µg/mL) in vitro was measured by MTT assay and cell apoptosis analysis. The distribution, anti-tumor effect and biological safety in vivo was evaluated on A375 nude mice. RESULTS: With the advantage of good penetration and targeting properties, Jug-PLGA-NPs significantly inhibited proliferation and migration of melanoma cells both in vitro and in vivo (P<0.05 or P<0.01) with acceptable biocompatibility. CONCLUSIONS Jug can inhibit the growth of melanoma but is highly toxic. With the advantage of sustained release, tumor targeting, anti-tumor activity and acceptable biological safety, Jug-PLGA-NPs provide a new pharmaceutical form for future application of Jug.
Animals ; Cell Line, Tumor ; Delayed-Action Preparations/therapeutic use* ; Drug Carriers/therapeutic use* ; Melanoma/pathology* ; Mice ; Mice, Nude ; Nanoparticles ; Naphthoquinones ; Particle Size ; Polylactic Acid-Polyglycolic Acid Copolymer/therapeutic use*

OBJECTIVE: It has been proven that acetylsalicylic acid (aspirin), as a kind of classical non-steroidal anti-inflammatory drug, not only has the effect of anti-inflammatory, but also has the function of immunity regulation and mineralization. However, it needs further investigation to study how to delay release of aspirin for a long time and enable to promote bone regeneration. Herein, we demonstrated that the longterm delayed release pattern of aspirin through the construction of microsphere scaffolds is promising to achieve the excellent bone regeneration. METHODS: Here we synthesized three kinds of scaffolds as follows: (1) aspirin loaded calcium silicate (CaSiO₃) microsphere (CaSiO₃-aspirin) via simple immersion; (2) aspirin loaded polylactic-co-glycolic acid (PLGA) microsphere (PLGA-aspirin) via oil/water (O/W) emulsion; (3) aspirin loaded PLGA-CaSiO₃ scaffold (PLGA-CaSiO₃-aspirin) via O/W emulsion, optimal morphology and structure of PLGA-CaSiO₃-aspirin scaffold was acquired through modulating the ratio between PLGA and CaSiO₃. Furthermore, spectrophotometer was used to monitor the concentration of the extract of the three scaffolds for different releasing time, including 1, 2, 4, 6, 9, 13, 17, 21, 24, 30, 36, and 45 days, aspirin loading efficiency and its accumulation releasing curves were both achieved according to the concentration of aspirin. Their sustained release effects of aspirin were evaluated eventually. RESULTS: Environmental scanning electron microscope (ESEM) results showed that the surface structure of the three kinds of scaffolds were smooth and had uniform size distribution. In addition, a small amount of PLGA-aspirin microspheres occurred to aggregation, while a small amount of CaSiO₃-aspirin microspheres were broken. Moreover, the PLGA-aspirin microspheres in the PLGA-CaSiO₃-aspirin scaffolds were uniformly adhered to the surface of CaSiO₃ microspheres. The aspirin loadings of CaSiO₃-aspirin, PLGA-aspirin, and PLGA-CaSiO₃-aspirin were (1.06±0.04)%, (7.05±0.06)%, and (6.75±0.18)%, respectively. In addition, their corresponding time for releasing 95% of aspirin was 3, 24, and 36 days, respectively. The releasing time of PLGA-CaSiO₃-aspirin was longer than that of the others and the releasing rate was more stable. CONCLUSION The microsphere scaffold of PLGA-CaSiO₃-aspirin composites has excellent delayedrelease effect on aspirin, which is promising for using as osteogenic materials.
Aspirin ; Delayed-Action Preparations ; Lactic Acid ; Microspheres ; Polyglycolic Acid ; Polylactic Acid-Polyglycolic Acid Copolymer

BACKGROUND: Absorbable plates are widely used in open reduction and internal fixation surgeries for facial bone fractures. Absorbable plates are made of polyglycolic acid (PGA), polylactic acid (PLA), polydioxane (PDS), or various combinations of these polymers. The degradation patterns of absorbable plates made from different polymers and clinical courses of patients treated with such plates have not been fully identified. This study aimed to confirm the clinical courses of facial bone fracture patients using absorbable plates and compare the degradation patterns of the plates. METHODS: A retrospective chart review was conducted for 47 cases in 46 patients who underwent open reduction and internal fixation surgery using absorbable plates to repair facial bone fractures. All surgeries used either PLA/PGA composite-based or poly-L-lactic acid (PLLA)/hydroxyapatite (HA) composite-based absorbable plates and screws. Clinical courses were confirmed and comparisons were conducted based on direct observation. RESULTS: There were no naturally occurring foreign body reactions. Post-traumatic inflammatory responses occurred in eight patients (nine cases), in which six recovered naturally with conservative treatment. The absorbable plates were removed from two patients. PLA/PGA composite-based absorbable plates degraded into fragments with non-uniform, sharp surfaces whereas PLLA/HA composite-based absorbable plates degraded into a soft powder. CONCLUSION: PLA/PGA composite-based and PLLA/HA composite-based absorbable plates showed no naturally occurring foreign body reactions and showed different degradation patterns. The absorbable plate used for facial bone fracture surgery needs to be selected in consideration of its degradation patterns.
Absorbable Implants ; Bone Plates ; Facial Bones ; Foreign Bodies ; Humans ; Hydroxyapatites ; Polyglycolic Acid ; Polymers ; Retrospective Studies

PURPOSE: Primary reconstruction via transconjunctival approach is a standardized treatment option for orbital floor fractures. The aim of this study was to compare the findings of specific ophthalmologic assessment with the patient's complaints after fracture reduction. METHODS: A retrospective medical chart analysis was performed on patients who had undergone transconjunctival orbital floor fracture reduction for fracture therapy with resorbable foil (ethisorb sheet or polydioxanone foil). A follow-up assessment including ophthalmological evaluation regarding visual acuity (eye chart projector), binocular visual field screening (Bagolini striated glasses test) and diplopia (cover test, Hess screen test) was conducted. Additionally, a questionnaire was performed to assess patients' satisfaction. RESULTS: A total of 53 patients with a mean follow-up of 23 months (ranging from 11 to 72) after surgical therapy were included. Diplopia was present preoperatively in 23 (43.4%) and reduced in follow-up examination (n = 12, 22.6%). Limitations in ocular motility reduced from 37.7% to 7.5%. The questionnaire about the patient's satisfaction revealed excellent outcomes in relation to the functional and esthetical parameters. CONCLUSION Transconjunctival approach is a safe approach for orbital fracture therapy. Postoperative diplopia is nearly never perceptible for the individual and differs to pathologic findings in the ophthalmic assessment.
Cohort Studies ; Diplopia ; diagnosis ; etiology ; Follow-Up Studies ; Fracture Fixation ; methods ; Orbital Fractures ; complications ; physiopathology ; psychology ; surgery ; Outcome Assessment (Health Care) ; Patient Satisfaction ; Polydioxanone ; administration & dosage ; Polyglycolic Acid ; administration & dosage ; Retrospective Studies ; Surveys and Questionnaires ; Treatment Outcome ; Visual Acuity ; Visual Fields

It is very useful to evaluate the content and 3D distribution of extracellular matrix non-destructively in tissue engineering. This study evaluated the feasibility of using micro-computed tomography (µCT) with Hexabrix to measure quantitatively sulfated glycosaminoglycans (GAGs) of engineered cartilage. Rabbit chondrocytes at passage 2 were used to produce artificial cartilages in polyglycolic acid scaffolds in vitro. Engineered cartilages were incubated with Hexabrix 320 for 20 min and analyzed via µCT scanning. The number of voxels in the 2D and 3D scanning images were counted to estimate the amount of sulfated GAGs. The optimal threshold value for quantification was determined by regression analysis. The 2D µCT images of an engineered cartilage showed positive correlation with the histological image of Safranin-O staining. Quantitative data obtained with the 3D µCT images of 14 engineered cartilages showed strong correlation with sulfated GAGs contents obtained by biochemical analysis (R² = 0.883, p < 0.001). Repeated exposure of engineered cartilages to Hexabrix 320 and µCT scanning did not significantly affect cell viability, total DNA content, or the total content of sulfated GAGs. We conclude that µCT imaging using Hexabrix 320 provides high spatial resolution and sensitivity to assess the content and 3D distribution of sulfated GAGs in engineered cartilages. It is expected to be a valuable tool to evaluate the quality of engineered cartilage for commercial development in the future.
Cartilage* ; Cell Survival ; Chondrocytes ; DNA ; Extracellular Matrix ; Glycosaminoglycans* ; In Vitro Techniques ; Ioxaglic Acid ; Polyglycolic Acid ; Tissue Engineering

A 68-year-old man presented with a posterior tracheal wall injury caused by percutaneous dilatational tracheostomy. The wound was immediately covered with an absorbable polyglycolic acid sheet. Ten days after the injury, the perforation was closed with knotless sutures using a Castroviejo needle-holder through the tracheostomy. The successful repair in this case indicates the feasibility of the knotless suture technique for perforations. The technique is described in detail in this report. The patient was weaned from the mechanical ventilator on postoperative day 25. In cases of posterior tracheal posterior wall perforation, every effort should be made to repair the perforation through an existing opening.
Aged ; Bronchoscopy ; Humans ; Polyglycolic Acid ; Suture Techniques ; Sutures* ; Tracheostomy* ; Ventilators, Mechanical ; Wounds and Injuries

Thread-embedding therapy has been widely applied for cosmetic purposes such as wrinkle reduction and skin tightening. Particularly, gold thread was reported to support connective tissue regeneration, but, its role in hair biology remains largely unknown due to lack of investigation. When we implanted gold thread and Happy Lift™ in human patient for facial lifting, we unexpectedly found an increase of hair regrowth in spite of no use of hair growth medications. When embedded into the depilated dorsal skin of mice, gold thread or polyglycolic acid (PGA) thread, similarly to 5% minoxidil, significantly increased the number of hair follicles on day 14 after implantation. And, hair re-growth promotion in the gold threadimplanted mice were significantly higher than that in PGA thread group on day 11 after depilation. In particular, the skin tissue of gold thread-implanted mice showed stronger PCNA staining and higher collagen density compared with control mice. These results indicate that gold thread implantation can be an effective way to promote hair re-growth although further confirmatory study is needed for more information on therapeutic mechanisms and long-term safety.
Animals ; Biology ; Collagen ; Connective Tissue ; Hair Follicle ; Hair Removal ; Hair* ; Humans* ; Lifting ; Mice* ; Minoxidil ; Polyglycolic Acid ; Proliferating Cell Nuclear Antigen ; Regeneration ; Skin

Gastrointestinal (GI) leakage, fistulae, and perforations can be serious and life threatening. There has been a paradigm shift in the management approach of these conditions, from surgical to conservative, including endoscopic management. Here, we report two cases of endoscopic closure of a GI fistula and perforation using polyglycolic acid (PGA) sheets with fibrin glue. The first case is of an anastomotic leak detected after subtotal gastrectomy with gastroduodenostomy. After failed application of endoclips, a PGA sheet was applied, and the fistula was successfully closed. The second case was of a 15-mm large perforated gastric ulcer, which was also successfully closed with a PGA sheet. This is the first case report that PGA sheet was used for the treatment of overt perforation. The outcome of these cases suggest that endoscopic closure using PGA sheets can be considered as a useful alternative for the management of GI leakage, fistulae, and perforations.
Anastomotic Leak ; Fibrin Tissue Adhesive ; Fistula ; Gastrectomy ; Polyglycolic Acid* ; Stomach Ulcer