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PubMed1996

Periadventitial delivery of heparin in the prevention of microvenous thrombosis.

PURPOSE: In spite of advances in technique and instrumentation, microvascular free tissue transfer remains associated with a persistent risk of flap failure. The use of systemic anticoagulants to overcome the formation of vasoocclusive thrombi at reactive anastomotic sites is associated with a high rate of flap hematoma and is ill advised in the operative setting. The purpose of this study was to investigate the use of a biodegradable, nontoxic polymer gel (polyvinyl alcohol, PVA) to effect a sustained localized release of perivascular heparin around thrombogenic venous anastomoses. MATERIALS AND METHODS: A modified adventitial inclusion model was created in the femoral vein of 64 adult female Sprague-Dawley rats. Animals were divided into four experimental groups: 1) no treatment (controls), 2) periadventitial PVA gel contained in a vicryl chamber, 3) periadventitial PVA gel mixed with heparin, and 4) systemic heparin (intravenous pump). Patency rates in the femoral vein were checked at 10 minutes, 1 hour, 1 day, and 4 days after surgery. Systemic coagulation parameters and histology (scanning electron microscopy, SEM) were assessed in representative animals from all groups. RESULTS: Patency rates for experimental groups showed a significant improvement in animals treated with PVA/heparin and systemic heparin over controls. Wound hematomas occurred in 7 of 16 animals in group 3, and in 4 of 16 animals in group 4. Activated partial thromboplastin times were elevated in group 4 only (> 150 seconds). CONCLUSIONS: Continuous release of periadventitial heparin using a polymeric delivery system may represent an efficient means of attenuating the reactivity of microvenous anastomoses without affecting systemic coagulation parameters. In this model, however, its use was associated with a high rate of local wound hematoma.

Animals↗
PubMed1999

Sulbactam-cefoperazone polyhydroxybutyrate-co-hydroxyvalerate (PHBV) local antibiotic delivery system: in vivo effectiveness and biocompatibility in the treatment of implant-related experimental osteomyelitis.

In this study, a novel antibiotic carrier system for use in the treatment of implant-related and chronic osteomyelitis was developed. Sulbactam-cefoperazone was introduced to rods of polyhydroxybutyrate-co-hydroxyvalerate (22 mol % HV, w/w), a member of a family of microbial-origin polymer that is biodegradable, biocompatible, and osteoconductive due to its piezoelectric property. The antibiotic-loaded carrier was implanted into the infection site that was induced by Staphylococcus aureus inoculation into the rabbit tibia. The effectiveness of this was assessed macroscopically, radiographically, bacteriologically, and histopathologically. Findings of infection subsided on day 15 and almost complete remission was observed on day 30. The control side that contained antibiotic-free rods, however, worsened. These findings prompted us to conclude that the novel biodegradable antibiotic carrier developed in the present study seems to be a promising candidate for use in the treatment of severe bone infection.

Animals↗
PubMed2006

Interstitial docetaxel (taxotere), carmustine and combined interstitial therapy: a novel treatment for experimental malignant glioma.

Docetaxel (Taxotere) is a hemisynthetic, anti-cancer compound with good preclinical and clinical activity in a variety of systemic neoplasms. We tested its activity against malignant gliomas using local delivery methods. Antitumor activity was assessed in vitro against human (U87 and U80 glioma) and rat brain-tumor (9L gliosarcoma and F98 glioma) cell lines. For in vivo evaluation, we incorporated docetaxel into a biodegradable polymer matrix, determined associated toxicity in the rat brain, and measured efficacy at extending survival in a rat model of malignant glioma. Also, we examined the combined local delivery of docetaxel with carmustine (BCNU) against the experimental intracranial glioma. Rats bearing intracranial 9L gliosarcomas were treated 5 days after tumor implantation with various polymers (placebo, 5% docetaxel, 3.8% BCNU, or 5% docetaxel and 3.8% BCNU combination). Animals receiving docetaxel polymers (n=15, median survival 39.1 days) had significantly improved survival over control animals (n=12, median survival 22.5 days, P=0.01). Similarly, animals receiving BCNU polymers (n=15, median survival 39.3 days, 13.3% long-term survivors) demonstrated an increase in survival compared to the controls (P=0.04). Animals receiving the combination polymers demonstrated a modest increase in survival compared to either chemotherapeutic agent alone (n=14, median survival 54.9 days, 28.6% long-term survivors) with markedly improved survival over controls (P=0.003). We conclude that locally delivered docetaxel shows promise as a novel anti-glioma therapy and that the combination of drug regimens via biodegradable polymers may be a great therapeutic benefit to patients with malignant glioma.

Absorbable Implants↗
PubMed2004

Poly-epsilon-caprolactone microspheres and nanospheres: an overview.

Poly-epsilon-caprolactone (PCL) is a biodegradable, biocompatible and semicrystalline polymer having a very low glass transition temperature. Due to its slow degradation, PCL is ideally suitable for long-term delivery extending over a period of more than one year. This has led to its application in the preparation of different delivery systems in the form of microspheres, nanospheres and implants. Various categories of drugs have been encapsulated in PCL for targeted drug delivery and for controlled drug release. Microspheres of PCL either alone or of PCL copolymers have been prepared to obtain the drug release characteristics. This article reviews the advancements made in PCL-based microspheres and nanospheres with special reference to the method of preparation of these and their suitability in developing effective delivery systems.

Animals↗
PubMed2000

Controlled and targeted drug delivery strategies towards intraperiodontal pocket diseases.

Advances in the understanding of the aetiology, epidemiology, pathogenesis and microbiology of periodontal pocket flora have revolutionized the strategies for the management of intraperiodontal pocket diseases. Intra-pocket, sustained release, drug delivery devices have been shown to be clinically effective in the treatment of periodontal infections. Several degradable and non-degradable devices are under investigation for the delivery of antimicrobial agents into the periodontal pocket including non-biodegradable fibres, films (biodegradable and non-biodegradable), bio-absorbable dental materials, biodegradable gels/ointments, injectables and microcapsules. With the realization that pocket bacteria accumulate as biofilms, studies are now being directed towards eliminating/killing biofilm concentrations rather than their planktonic (fluid phase) counterparts. Intraperiodontal pocket drug delivery has emerged as a novel paradigm for the future research. Similarly, bioadhesive delivery systems are explored that could significantly improve oral therapeutics for periodontal disease and mucosal lesions. A strategy is to target a wide range of molecular mediators of tissue destruction and hence arrest periodontal disease progression. Research into regenerating periodontal structures lost as a result of disease has also shown substantial progress in the last 25 years.

Biofilms↗
PubMed2000

[Development of biodegradable polymer scaffolds for bone tissue engineering].

OBJECTIVE: To investigate the selection and manufacture of ideal extracellular matrix materials in bone tissue engineering. METHODS: The recent literatures about biodegradable polymers served as culture scaffolds of osteoblasts were widely reviewed, the advantages and disadvantages of biodegradable synthetic polymers and natural polymers were analysed. RESULTS: The ideal extracellular matrix material in bone tissue engineering should be made up of inorganic materials, synthetic polymers and natural polymers, which possesses morphological structure of three-dimensional foam with self-mediated drug slow delivery system of bone growth factors. CONCLUSION: The design and manufacture of combined extracellular matrix materials in bone tissue engineering is a very important and urgent challenge.

Absorbable Implants↗
PubMed1997

Ex vivo degradation of a poly(propylene glycol-fumarate) biodegradable particulate composite bone cement.

We have developed a biodegradable particulate composite bone cement consisting of a poly(propylene glycolfumarate)-(methylmethacrylate) matrix mixed with calcium carbonate and tricalcium phosphate particulates. Previous ex vivo studies suggest that this system provides sufficient strength for a number of potential clinical applications including structural reinforcement of osseous defects, internal fixation devices for age-related fractures, and delivery of antibiotics to treat osteomyelitis. As a first step toward investigating in vivo responses to this material, we studied the influence of varied concentrations of crosslinker, accelerator, and free radical on the mechanical properties of the cement. We then developed an ex vivo degradation assay and correlated the mechanical properties of degrading cement with the temporal changes in chemical properties of both the cement and the bathing medium. The optimal cement formulation was composed of one-third poly(propylene glycolfumarate)-(methylmethacrylate), one-third calcium carbonate, and one-third tricalcium phosphate, and provided initial compressive strengths of up to 30 MPa and compressive moduli of up to 300 MPa. Degradation rates, measured by a decline in mechanical properties, dissolution of calcium from the cement, and change in pH of the bathing medium, could be controlled by changing the concentration of reactants in the matrix. Specifically, an increase in methylmeth-acrylate or increase in both methylmethacrylate and benzoyl peroxide was inversely proportional to the rate of degradation and directly proportional to the initial mechanical properties. The degradation products and environmental changes appear to be compatible with physiologic remodeling and therefore justify examination of the in vivo response to implantation of this material.

Analysis of Variance↗
PubMed2006

Therapeutic potential of chitosan and its derivatives in regenerative medicine.

BACKGROUND: Cell-based transplantation, tissue engineering and gene therapy are important therapeutic strategies for present and future regenerative medicine. One challenge is to present the target cells in a suitable matrix to allow the cells to survive the wound contraction, tissue repair, and remodeling in certain tissues. Recently, functional biomaterial research has been directed towards the development of improved scaffolds and new drug delivery systems for regenerative medicine. MATERIALS AND METHODS: A literature survey was performed in basic and clinic publications relevant to the therapeutic potential of chitosan and its derivatives in regenerative medicine. In this review the functional properties and potential applications of chitosan and its derivatives in regenerative medicine are presented and discussed. RESULTS: Chitosan can be obtained by alkaline deacetylation of chitin and is found to be a natural-based nontoxic, biocompatible, and biodegradable polymer with anti-microbial activity. Chitosan and its derivatives could accelerate wound healing by enhancing the functions of inflammatory cells and repairing cells. Recent studies further indicated that chitosan and its derivatives also are novel scaffold materials for tissue engineering and are-promising non-viral vectors for gene delivery. CONCLUSIONS: Regenerative medicine has entered a new era with the development of modern science and technology. The novel properties of chitosan make it a versatile biomaterial for cell therapy, tissue engineering and gene therapy. It is hoped that these diverse approaches for regenerative medicine will translate from "bench to bedside" in the future.

Animals↗
PubMed2000

Synthesis and characterization of surface-hydrophobic ion-exchange microspheres and the effect of coating on drug release rate.

Biodegradable, dextran-based ion-exchange microspheres (IE-MS) have been used for localized delivery of anticancer drugs and chemosensitizers. Because of their hydrophilic nature, the IE-MS release their payload quickly. The purpose of this work was to develop an IE-MS system that could provide a broad range of release rates for in vitro and in vivo applications. Sulfopropylated dextran microspheres (SP C25 MS) were surface-modified by acylation. These hydrophobically modified sulfopropylated dextran microspheres (HM-MS) were further coated with the cationic acrylic polymer Eudragit RL100 (EU-MS). The changes in chemical composition after the surface modification and coating were characterized by X-ray photoelectron spectroscopy. The effects of the modification and coating on the surface hydrophobicity, equilibrium swelling, surface morphology, and drug loading capacity were investigated. The HM-MS showed little change in swelling and functionality, despite significantly increased affinity to oil and carbon content on the surface. The coated microspheres (EU-MS) exhibited a profoundly decreased swelling ratio, an even higher affinity to oil, a higher loading capacity, and a lower drug release rate. Through further coating of the EU-MS with different amounts of corn oil, the rate of drug release could be tailored to cover a relatively wide range. These results suggest that a versatile delivery system with various release profiles can be prepared by a combination of hydrophobic modification, polymer coating, and oil coating.

Ion Exchange Resins↗
PubMed1985

The use of controlled-release glass for the controlled delivery of bioactive materials.

CRG can provide a useful supplement to other methods of controlled delivery. Some advantages of this approach are: The constituents of the CRG can be limited to biologically safe ionic species such as Na+, Ca2+ and PO4(3-). The release system is completely soluble in water and no residue remains. There is no evidence of any mechanism for biodegradation of the CRG and so one possible cause of premature or accelerated release is eliminated. The absolute release rate can be selected anywhere in a spectrum covering several orders of magnitude and the rate-controlling process has zero-order kinetics. The release rate can be selected to be pH-sensitive or pH-independent. Complex temporal release-rate patterns can be obtained readily by the choice of geometrical shape or composition profile of the device. The controlled release of organics or other heat-sensitive materials which cannot be incorporated in the glass can be realized by the use of composite structures in which the CRG is the rate-controlling constituent. A number of different functions can be performed by a single CRG-based device. For example, CRG can be used as a biomedical resorbable material in surgery and the CRG structural component can release an AM as it dissolves. Similarly the CRG of the sinter-composite used for organic AM release can itself release any selected inorganic adjuvant. CRG boluses containing either copper or cobalt and weighing approx. either 70 g or 15 g, have been administered to both cattle and sheep. More than 90% of the boluses remained either in the reticulum of trace element remained after dosing.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Ciprofloxacin-loaded bovine serum albumin microspheres: preparation and drug-release in vitro.

Ciprofloxacin albumin microspheres were prepared by the spray drying technique, with bovine serum albumin as the natural biodegradable wall material. The spherical microspheres, flowed well, were organic solvent free and in the size range 1-5 microm. The drug release from the microspheres could be retarded by further thermal denaturation. The sustained-release microspheres were suitable for dry powder inhaled lung drug delivery systems.

Animals↗
PubMed2005

Subconjunctivally administered celecoxib-PLGA microparticles sustain retinal drug levels and alleviate diabetes-induced oxidative stress in a rat model.

We have previously reported that repeated oral doses of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, reduced diabetes-induced retinal vascular endothelial growth factor (VEGF) expression [Ayalasomayajula, S.P., Kompella, U.B., 2003. Celecoxib, a selective cyclooxygenase-2 inhibitor, inhibits retinal vascular endothelial growth factor expression and vascular leakage in a streptozotocin-induced diabetic rat model. Eur J Pharmacol 458, 283-289] and that retinal celecoxib delivery can be improved by several-fold following subconjunctival administration [Ayalasomayajula, S.P., Kompella, U.B., 2004. Retinal delivery of celecoxib is several-fold higher following subconjunctival administration compared to systemic administration. Pharm Res 21, 1797-1804]. The objective of the current study was to determine whether polymeric microparticles of celecoxib sustain retinal drug levels following subconjunctival administration and alleviate diabetes-induced oxidative stress in a streptozotocin-induced diabetic rat model. Biodegradable poly (lactide-co-glycolide) (PLGA; 85:15) microparticles of celecoxib were prepared using solvent evaporation method and characterized for their size, morphology, encapsulation efficiencies, and in vitro release. The celecoxib-PLGA microparticles or solution containing 75 microg of celecoxib was administered subconjunctivally to one eye (ipsilateral) of Sprague Dawley rats and drug levels in the retina, vitreous, lens, and cornea of ipsilateral and contralateral eyes were determined on 1, 7, and 14 days using high-performance liquid chromatography (HPLC). The effect of subconjunctivally administered celecoxib-PLGA microparticles on oxidative stress in day 14 diabetic rat retinas was determined by measuring the retinal glutathione (reduced (GSH) and oxidized (GSSG)), thiobarbituric acid reactive substances, and 4-hydroxynonenal levels using spectrofluorometric and colorimetric methods. Solvent evaporation method produced spherical celecoxib-PLGA microparticles with mean diameters of 3.9+/-0.6 microm and 68.5% loading efficiency. These microparticles sustained celecoxib release during the 49-day in vitro release study. Subconjunctivally administered celecoxib-PLGA microparticles sustained retinal and other ocular tissue drug levels during the 14-day study in rats. No detectable celecoxib levels were observed in the contralateral eye. The celecoxib-PLGA microparticles significantly inhibited the diabetes-induced increases in thiobarbituric acid reactive substance (P=0.012) and 4-hydroxynonenal levels (P=0.029). The particles also inhibited the GSH depletion and the increase in GSSH/GSH ratio associated with diabetes but the effects were not statistically significant (P=0.12). Thus, following subconjunctival administration, celecoxib-PLGA microparticles sustained retinal celecoxib delivery and inhibited diabetes-induced retinal oxidative damage, indicating their potential usefulness in treating diabetes-induced retinal abnormalities.

Aldehydes↗
PubMed2004

Chemistry of polymer biodegradation and implications on parenteral drug delivery.

Most polymeric implants are biodegraded by one of two common chemical degradation mechanisms: (i). hydrolysis and (ii). oxidation. The chemical structure is among the most important factors which affect the biodegradation of polymeric implants. Hydrolytic biodegradations are often accompanied by substantial decrease of pH, whilst oxidative biodegradation processes are usually very slow due to consumption of stoichiometric amounts of oxidising agents. A dramatic acceleration of the biodegradation can be expected, if the biodegradation can be initiated by catalytic amounts of oxidation agents. Poly(ethylene carbonate) (PEC) and poly(trimethylene carbonate) (PTMC) are presumably biodegraded by such catalytic oxidation processes. Their biodegradation shows all the characteristics of surface erosion. Poly(ethylene carbonate) is utilised as a surface eroding biocompatible polymer for controlled delivery of peptide and protein drugs.

Animals↗
PubMed2006

Polyionic hydrocolloids for the intestinal delivery of protein drugs: alginate and chitosan--a review.

The protein pharmaceutical market is rapidly growing, since it is gaining support from the recombinant DNA technology. To deliver these drugs via the oral route, the most preferred route, is the toughest challenge. In the design of oral delivery of peptide or protein drugs, pH sensitive hydrogels like alginate and chitosan have attracted increasing attention, since most of the synthetic polymers are immunogenic and the incorporation of proteins in to these polymers require harsh environment which may denature and inactivate the desired protein. Alginate is a water-soluble linear polysaccharide composed of alternating blocks of 1-4 linked alpha-L-guluronic and beta-D-mannuronic acid residues where as chitosan is a co polymer of D-glucosamine and N-acetyl glucosamine. The incorporation of protein into these two matrices can be done under relatively mild environment and hence the chances of protein denaturation are minimal. The limitations of these polymers, like drug leaching during preparation can be overcome by different techniques which increase their encapsulation efficiency. Alginate, being an anionic polymer with carboxyl end groups, is a good mucoadhesive agent. The pore size of alginate gel microbeads has been shown to be between 5 and 200 nm and coated beads and microspheres are found to be better oral delivery vehicles. Cross-linked alginate has more capacity to retain the entrapped drugs and mixing of alginate with other polymers such as neutral gums, pectin, chitosan, and eudragit have been found to solve the problem of drug leaching. Chitosan has only limited ability for controlling the release of encapsulated compound due to its hydrophilic nature and easy solubility in acidic medium. By simple covalent modifications of the polymer, its physicochemical properties can be changed and can be made suitable for the peroral drug delivery purpose. Ionic interactions between positively charged amino groups in chitosan and the negatively charged mucus gel layer make it mucoadhesive. The favourable properties like biocompatibility, biodegradability, pH sensitiveness, mucoadhesiveness, etc. has enabled these polymers to become the choice of the pharmacologists as oral delivery matrices for proteins.

Alginates↗
PubMed2001

[Studies on lung targeted niosomes of carboplatin].

AIM: To improve the treatment efficacy and reduce the side effect of carboplatin (CBP), the antitumor drug was incorporated into niosomes (NS). METHODS: Lung targeted niosomes of CBP (CBP-NS) were prepared by the method of hand shaking. The ultraviolet absorption spectrophotometric method was used for the determination of CBP. The method of dynamic dialysis was used for in vitro release of CBP from CBP-NS. The S-180 lung neoplasms models were established by i.v. cancer cells in mice. The number of pulmonary nodules was examined for evaluating the therapeutic efficacy. RESULTS: The data showed that the mean diameter of CBP-NS was 3.72 microns, with a span of 0.66. The entrapment ratio of CBP in CBP-NS was 29.2% and the CBP-NS were stable for three months stored at 3 degrees C-5 degrees C, 15 degrees C-25 degrees C or 37 degrees C (relative humidity 75%). The release profile in vitro could be described by a biexpotential equation. The calculated values of the three targeting parameters indicated that CBP-NS showed good targeting efficiency. The results of therapeutic trials showed that the antitumor effects were significantly increased by injection of CBP-NS compared with CBP in the treatment of mice with lung carcinoma. CONCLUSION: The results indicated that CBP-NS have good targeting efficiency in vivo, and the biodegradable CBP-NS may decrease the side effects of carboplatin and improve its therapeutic efficacy.

Animals↗
PubMed2002

Local delivery of mitoxantrone for the treatment of malignant brain tumors in rats.

OBJECT: Mitoxantrone is a drug with potent in vitro activity against malignant brain tumor cell lines; however, its effectiveness as a systemic agent has been hampered by poor central nervous system penetration and dose-limiting myelosuppression. To avoid these problems, we incorporated mitoxantrone into biodegradable polymeric wafers to be used for intracranial implantation, a strategy that has been shown to be safe and successful in the treatment of malignant gliomas. The authors investigated the release kinetics, toxicity, distribution, and efficacy of mitoxantrone delivered from intracranially implanted biodegradable wafers in the treatment of 9L gliosarcoma in Fischer 344 rats. METHODS: Mitoxantrone released from the biodegradable wafer matrix reached therapeutic drug concentrations in the brain for at least 35 days. Only animals with implanted wafers of the highest drug loading dose (20% mitoxantrone by weight) showed signs of significant toxicity. In three separate efficacy experiments, animals treated with mitoxantrone-loaded biodegradable wafers had significantly improved survival compared with control animals. The combined median survival for each treatment group was the following: 0% mitoxantrone wafers, 19 days; 1%, 30 days, p < 0.0001; 5%, 34 days, p < 0.0001; and 10%, 50 days, p < 0.0001. CONCLUSIONS: These findings establish that mitoxantrone delivered from intracranially implanted biodegradable wafers is effective in the treatment of malignant gliomas in rodents and should be considered for future clinical application in humans.

Animals↗
PubMed2005

In vivo tumor transfection mediated by polyplexes based on biodegradable poly(DMAEA)-phosphazene.

In recent years, increasing interest is being paid to the design of transfectants based on non-toxic and biodegradable polymers for gene therapy purposes. We recently reported on a novel, biodegradable polymer, poly(2-dimethylamino ethylamino)phosphazene (p(DMAEA)-ppz) for use in non-viral gene delivery. In this study, the biodistribution and in vivo transfection efficiency of polyplexes composed of plasmid DNA and p(DMAEA)-ppz were investigated after intravenous administration in tumor bearing mice. Data were compared with those of polyplexes based on the non-biodegradable polyethylenimine (PEI 22kDa). Both polyplex systems were rapidly cleared from the circulation (<7% ID, at 60 min after administration) and showed considerable disposition in the liver and the lung, all in line with earlier work on cationic polyplex systems. The lung disposition is attributed to aggregates formed by interaction of the polyplexes with blood constituents. Redistribution of the polyplexes from the lung was observed for both polyplex formulations. Importantly, both polyplex systems showed a substantial tumor accumulation of 5% and 8% ID/g for p(DMAEA)-ppz and PEI22 polyplexes, respectively, at 240 min after administration. The tumor disposition of the p(DMAEA)-ppz and PEI22 polyplexes was associated with considerable expression levels of the reporter gene. In contrast to PEI22 polyplexes, p(DMAEA)-ppz polyplexes did not display substantial gene expression in the lung or other organs (organ gene expression<1/100 of tumor gene expression). The observed preferential tumor gene expression mediated by the p(DMAEA)-ppz polyplexes enables the application of this polymer to deliver therapeutic genes to tumors.

Animals↗
PubMed2002

Biodegradable polymer grafts for surgical repair of the injured spinal cord.

PURPOSE: Biodegradable polymers have been used in the surgical repair of peripheral nerves, but their potential for use in the central nervous system has not been exploited adequately. This article discusses concepts related to the engineering of a biodegradable polymer graft for surgical repair of the injured spinal cord and explores the potential means by which such a device might promote axon regeneration and functional recovery after spinal cord injury. CONCEPT: A biodegradable polymer implant with controlled microarchitecture can be engineered, and its composition can be optimized for implantation in the spinal cord. RATIONALE: The use of a biodegradable polymer implant has the dual advantages of providing a structural scaffold for axon growth and a conduit for sustained-release delivery of therapeutic agents. As a scaffold, the microarchitecture of the implant can be engineered for optimal axon growth and transplantation of permissive cell types. As a conduit for the delivery of therapeutic agents that may promote axon regeneration, the biodegradable polymer offers an elegant solution to the problems of local delivery and controlled release over time. Thus, a biodegradable polymer graft would theoretically provide an optimal structural, cellular, and molecular framework for the regrowth of axons across a spinal cord lesion and, ultimately, neurological recovery. CONCLUSION: Biodegradable polymer grafts may have significant therapeutic potential in the surgical repair of the injured spinal cord. Further research should be focused on the bioengineering, characterization, and experimental application of these devices.

Absorbable Implants↗