OBJECTIVETo explore the method to repair bone defect with bone-morphogenetic-protein loaded hydroxyapatite/collagen-poly(L-lactic acid) composite.

METHODS18 adult beagle dogs were randomly divided into 3 groups. In Group A, bone-morphogenetic-protein (BMP) loaded hydroxyapatite/collagen-poly(L-lactic acid) (HAC-PLA) scaffold was implanted in a 2 cm diaphyseal defect in the radius. In Group B, unloaded pure HAC-PLA scaffold was implanted in the defects. No material was implanted in Group C (control group). The dogs were sacrificed 6 months postoperatively. Features of biocompatibility, biodegradability and osteoinduction were evaluated with histological, radiological examinations and bone mineral density (BMD) measurements.

RESULTSIn Group A, the radius defect healed after the treatment with BMP loaded HAC-PLA. BMD at the site of the defect was higher than that of the contralateral radius. Fibrous union developed in the animals of the control group.

CONCLUSIONSBMP not only promotes osteogenesis but also accelerates degradation of the biomaterials. Optimized design parameters of a three-dimensional porous biomaterial would give full scope to the role of BMP as an osteoinductive growth factor.

Animals ; Biocompatible Materials ; therapeutic use ; Bone Morphogenetic Proteins ; therapeutic use ; Bone Substitutes ; therapeutic use ; Collagen ; therapeutic use ; Dogs ; Durapatite ; therapeutic use ; Lactic Acid ; therapeutic use ; Microscopy, Electron, Scanning ; Osseointegration ; Osteogenesis ; Radiography ; Radius ; diagnostic imaging ; pathology ; Wound Healing ; physiology

This study aims at restoring the skin from traumatism by use of the collagen(from piglet skin) and konjac glucomannan-chondroitin sulfate blend film. The 2 cm x 4 cm skin traumatism model was established on both sides of the waist spinal column in 14 New Zealand rabbits each weighing 1.5-2.0 kg. One side was covered with blend film, the other side was used as a control. Then the changes of the skin traumatism were observed at different time-points after the operation, the wound tissue samples were taken for histological examination. The blend film could prevent skin traumatism from bleeding and infection. The skin traumatism treated by blend film showed signs of rectangle scab and the control showed signs of linear scab after healing. No obvious immune rejection was seen. The collagen-konjac glucomannan-chondroitin sulfate blend film can accelerate the restoration of skin from traumatism.
Animals ; Chondroitin Sulfates ; therapeutic use ; Collagen ; therapeutic use ; Female ; Male ; Mannans ; therapeutic use ; Membranes, Artificial ; Rabbits ; Skin ; injuries ; Skin Ulcer ; drug therapy ; Wound Healing ; drug effects

OBJECTIVETo seek new method for the treatment of peripheral nerve injury.

METHODSIn rat model with sciatic nerve defect, chitosan-collagen film was sutured into conduit to bridge 5 mm, 10 mm nerve defects. Rats that underwent end-to-end anastomosis were taken as controls. General observation, electrophysiological study, histological study and image analysis were performed at 4, 8, 12 weeks postoperatively.

RESULTSIn 5 mm nerve defects, the quality of nerve regeneration was similar to that of the control group. For 10 mm nerve defect, nerve regeneration was inferior to that of the control group. Chitosan-collagen film obviously degraded at 12 weeks postoperatively.

CONCLUSIONSChitosan-collagen film conduit can be used to bridge peripheral nerve defect.

Animals ; Biocompatible Materials ; therapeutic use ; Chitin ; analogs & derivatives ; therapeutic use ; Chitosan ; Collagen ; therapeutic use ; Male ; Models, Animal ; Nerve Regeneration ; Rats ; Rats, Wistar ; Sciatic Nerve ; injuries ; physiology ; surgery

OBJECTIVES: Steroidal anti-inflammatory drugs have certain side effects in the treatment of hypertrophic scar, and the scar recurrence is easy after withdrawal of steroid anti-inflammatory drugs. Finding reliable alternative drugs is an effective means to improve this defect. Aspirin, a traditional non-steroidal anti-inflammatory drug, is safe for topical use and has anti-inflammatory effects similar to those of steroidal anti-inflammatory drugs, which may have similar effects on the treatment of hypertrophic scar. This study aims to investigate the inhibitory effect of aspirin on the proliferation of hypertrophic scar in rabbit ears and the underlying mechanism. METHODS: The rabbit ear hypertrophic scar models were prepared. The rabbits were randomly divided into a normal skin group (group A), a blank control group (group B), a 0.9% NaCl group (group C), a 0.2% aspirin group (group D), a 0.5% aspirin group (group E), a 2% aspirin group (group F), and a triamcinolone acetonide group (group G). Macroscopic observation of hyperplasia was performed 8 weeks after local injection of the scar, followed by collecting the scar tissue samples for HE staining, Masson staining, and immunohistochemistry, respectively to assess the proliferation of fibroblasts and collagen fibers, and calculate the hypertrophic index, microvessel density, and immunohistochemical score. RESULTS: All rabbit ear hypertrophic scar models were successfully constructed. In groups B and C, the hypertrophic scar edge was irregular, with reddish protruding epidermis, significant contracture and hard touch. In group D, E, and F, with the increase of aspirin administration concentration, the scar became thinner and gradually flat, the proliferation of fibrocytes and collagen fibers was weakened, and the hypertrophic index was gradually decreased (P<0.05). Immunohistochemistry showed that the expression of β-catenin was decreased in the group D, E and F in turn, and the immunohistochemical score was gradually decreased (P<0.05). There was no significant difference in hypertrophic index, microvessel density, and immunohistochemical score (all P>0.05). CONCLUSIONS Local injection of aspirin can reduce the generation of hypertrophic scar in a dose-dependent manner within a certain concentration range; aspirin inhibits the growth of hypertrophic scar in rabbit ears by inhibiting Wnt/β-catenin signal pathway; 2% aspirin and 40 mg/mL triamcinolone acetonide have similar curative efficacy on hypertrophic scar.
Animals ; Anti-Inflammatory Agents/therapeutic use* ; Aspirin/therapeutic use* ; Cicatrix, Hypertrophic/pathology* ; Collagen ; Rabbits ; Signal Transduction ; Triamcinolone Acetonide/therapeutic use* ; beta Catenin/metabolism*

Lyodura(R) is a commercial name of a cleaned, desantigenized, desenzymatized, rendered free of pyogenics, sterilized by gamma rays, and lyophilized dura. Frontalis suspension with Lyodura(R) was performed on a total of 16 patients (21 lids) of congenital ptosis with levator muscle function of 3mm or less in the ptotic lid. The follow-up period ranged from 2 to 39 weeks with a mean of 19.6 weeks. Postperative lid levels were judged good, fair, and poor. Good results occurred in 12 of 21 procedures (57.1%) and fair results in 6 of 21 procedures (28.6%). The summation of these two indicates an over all satisfactory result of 18 of 21 cases (85.7%).
Blepharoptosis/*congenital/therapy ; Child ; Child, Preschool ; Collagen/*therapeutic use ; Eyelids/surgery ; Humans ; Infant

Scarring, naturally induced by fibroblasts(Fb) during wound healing, is an essential process in response to repair damaged tissue. Excessive Fb proliferation which produces the excessive collagen deposition, including increased extracellular matrix synthesis or insufficient decomposition, typically contributes to hypertrophic scar(HS) formation. Although exact mechanisms of HS are not yet fully understood, it is generally believed that dysfunction of Fb and regulation of signal pathways play an important role in HS formation. Biologically, Fb function is affected by various factors such as cytokines, extracellular matrix and itself. In addition, modifications of miRNA, ceRNA, lncRNA, peptides and histones participate in HS formation by affecting the biological function of Fb. Despite the clinical importance, very few therapeutic modalities are available to prevent HS. To achieve this, a deeper characterization of Fb is required to identify mechanisms of HS. To the aspect of HS prevention and treatment, we review recent findings, concentrating on Fb function and collagen secretion. The objective of this article is to frame the current understanding, gain the deeper insights into Fb function, and provide the more comprehensive cognition and perspective for prevention and treatment of HS.
Humans ; Cicatrix, Hypertrophic/metabolism* ; Collagen/therapeutic use* ; Fibroblasts ; Signal Transduction ; Extracellular Matrix/metabolism*

OBJECTIVE: This study assessed the outcomes of using vascular closure devices following percutaneous transfemoral endovascular procedures in the patients who were treated with heparin, abciximab or thrombolytics (urokinase or t-PA) during the procedures. MATERIALS AND METHODS: From March 28, 2003 to August 31, 2004, we conducted a prospective and randomized study in which 1,676 cases of 1,180 patients were treated with one of the two different closure devices (the collagen plug device was Angio-SealTM; the suture-mediated closure device was The Closer STM) at the femoral access site after instituting percutaneous endovascular procedures. Among the 1,676 cases, 108 cases (the drug group) were treated with heparin only (n = 94), thrombolytics only (n = 10), heparin and thrombolytics (n = 3), or abciximab and thrombolytics (n = 1) during the procedures; 1,568 cases (the no-drug group) were treated without any medication. We compared the efficacy and complications between the two groups. Of the drug group, 42 cases underwent arterial closures with the collagen plug devices and 66 cases underwent arterial closures with the suture-mediated closure devices. We also compared the efficacy and complications between these two groups. RESULTS: The immediate hemostasis rates were 92.9% (1,456/1,568) in the no-drug group and 91.7% (99/108) in the drug group. Early complications occurred in four cases of the drug group. These included two episodes of rebleeding with using the Closer S, which required manual compression for at least 10 minutes, and two episodes of minor oozing with using one Angio-Seal and one Closer S, which required two hours of additional bed rest. There was no late complication. So, the total success rates were 90.8% (1,423/1,568) in the no-drug group and 88.0% (95/108) in the drug group. These results were not significantly different between the two groups (p = 0.34). In the drug group, the difference of the successful hemostasis rate between the collagen plug devices and the suture-mediated devices was also not statistically significant (92.9% vs. 84.8%, respectively; p = 0.21). CONCLUSION: Arterial closure of the femoral access site with using vascular closure devices is both safe and effective, even in the patients who received heparin, abciximab or thrombolytics.
Sutures ; Prospective Studies ; Postoperative Complications ; Middle Aged ; Male ; Immunoglobulin Fab Fragments/pharmacology/*therapeutic use ; Humans ; Hemostatic Techniques/*instrumentation ; Hemostasis/*drug effects ; Fibrinolytic Agents/pharmacology/*therapeutic use ; Femoral Artery/*surgery ; Female ; Collagen ; Anticoagulants/pharmacology/*therapeutic use ; Antibodies, Monoclonal/pharmacology/*therapeutic use

Animals ; Biocompatible Materials ; therapeutic use ; Bone Regeneration ; Bone Substitutes ; therapeutic use ; Bone Transplantation ; Collagen ; therapeutic use ; Guided Tissue Regeneration, Periodontal ; methods ; Humans ; Membranes, Artificial ; Periodontal Diseases ; surgery ; Polytetrafluoroethylene ; therapeutic use

OBJECTIVETo fabricate bone grafts by bone marrow stromal cell combined with modified PLGA/Type-I collagen compound scaffold using tissue engineering method.

METHODSThe modified PLGA/Type-I collagen compound scaffold was fabricated. The rabbit primary cultured osteoblasts were identified and seeded onto the modified compound scaffold for one week in vitro. The adhesion and growth of cells were observed with scanning electron microscope. The complex of cells and scaffold was implanted into the subcutaneous region of rabbits and new bone formation was evaluated.

RESULTSThe rabbit bone marrow stromal cells were induced and differentiated into osteoblasts. The adhesion and growth of osteoblasts in cluster were observed on the surface of scaffolds. New bone formation was observed at one month postoperatively and active osteoblasts were found on the surface of the newly formed bone in vivo.

CONCLUSIONThe complex of PLGA and type-I collagen is an appropriate biodegradable scaffold and can be applied in bone tissue engineering.

Absorbable Implants ; Animals ; Biocompatible Materials ; Cells, Cultured ; Collagen Type I ; therapeutic use ; Female ; Femur ; cytology ; Lactic Acid ; therapeutic use ; Male ; Osteoblasts ; cytology ; Polyglycolic Acid ; therapeutic use ; Polymers ; therapeutic use ; Prostheses and Implants ; Rabbits ; Stents ; Stromal Cells ; cytology ; transplantation ; Tissue Engineering

The present study was undertaken to evaluate porous hydroxyapatite (HAp), the powder of which was prepared by a novel aqueous solution combustion technique, as a bone substitute in healing bone defects in vivo, as assessed by radiologic and histopathologic methods, oxytetracycline labeling, and angiogenic features in Bengal goat. Bone defects were created in the diaphysis of the radius and either not filled (group I) or filled with a HAp strut (group II). The radiologic study in group II showed the presence of unabsorbed implants which acted as a scaffold for new bone growth across the defect, and the quality of healing of the bone defect was almost indistinguishable from the control group, in which the defect was more or less similar, although the newly formed bony tissue was more organized when HAp was used. Histologic methods showed complete normal ossification with development of Haversian canals and well-defined osteoblasts at the periphery in group II, whereas the control group had moderate fibro-collagenization and an adequate amount of marrow material, fat cells, and blood vessels. An oxytetracycline labeling study showed moderate activity of new bone formation with crossing-over of new bone trabeculae along with the presence of resorption cavities in group II, whereas in the control group, the process of new bone formation was active from both ends and the defect site appeared as a homogenous non-fluoroscent area. Angiograms of the animals in the control group showed uniform angiogenesis in the defect site with establishment of trans-transplant angiogenesis, whereas in group II there was complete trans-transplant shunting of blood vessel communication. Porous HAp ceramic prepared by an aqueous combustion technique promoted bone formation over the defect, confirming their biologic osteoconductive property.
Angiography/veterinary ; Animals ; Collagen/*therapeutic use ; Durapatite/*therapeutic use ; Fractures, Bone/radiography/therapy/*veterinary ; Goat Diseases/*therapy ; Goats ; Osteogenesis/*physiology ; Oxytetracycline