Vancomycin Containing Plla/Β-Tcp Controls Experimental Osteomyelitis In Vivo

Background Implant-related osteomyelitis (IRO) is recently controlled with local antibiotic delivery systems to overcome conventional therapy disadvantages. In vivo evaluation of such systems is however too little. Questions/purposes We asked whether vancomycin (V)-containing poly-l-lactic acid/β-tricalcium phosphate (PLLA/β-TCP) composites control experimental IRO and promote bone healing in vivo. Methods Fifty-six rats were distributed to five groups in this longitudinal controlled study. Experimental IRO was established at tibiae by injecting methicillin-resistant Staphylococcus aureus (MRSA) suspensions with titanium particles in 32 rats. Vancomycin-free PLLA/β-TCP composites were implanted into the normal and infected tibiae, whereas V-PLLA/β-TCP composites and coated (C)-V-PLLA/β-TCP composites were implanted into IRO sites. Sham-operated tibiae established the control group. Radiological and histological scores were quantified with microbiological findings on weeks 1 and 6. Results IRO is resolved in the CV- and the V-PLLA/β-TCP groups but not in the PLLA/β-TCP group. MRSA was not isolated in the CV- and the V-PLLA/β-TCP groups at all times whereas the bacteria were present in the PLLA/β-TCP group. Radiological signs secondary to infection are improved from 10.9 ± 0.9 to 3.0 ± 0.3 in the V-PLLA/β-TCP group but remained constant in the PLLA/β-TCP group. Histology scores are improved from 24.7 ± 6.5 to 17.6 ± 4.8 and from 27.6 ± 7.9 to 32.4 ± 8.9 in the CV-PLLA/β-TCP and the V-PLLA/β-TCP groups, respectively. New bone was formed in all the PLLA/β-TCP group at weeks 1 and 6. Conclusions CV- and V-PLLA/β-TCP composites controlled experimental IRO and promoted bone healing. Clinical relevance CV- and V-PLLA/β-TCP composites have the potential of controlling experimental IRO and promoting bone healing.PubMedWoSScopu

Vancomycin Containing Plla/Beta-Tcp Controls Mrsa In Vitro

Osteomyelitis caused by Methicillin-resistant Staphylococcus aureus (MRSA) often requires surgery and prolonged systemic antibiotic treatment. Local antibiotic delivery systems of bioceramics or polymers have been developed to treat osteomyelitis. A disadvantage of biodegradable polymers is the initial burst of antibiotics into the environment; one advantage of bioceramics is its osteoconductivity. We therefore developed a vancomycin-containing poly-l-lactic acid/beta-tricalcium phosphate (PLLA/beta-TCP) composite to control antibiotic release and stimulate bone formation. We (1) characterized these composites, (2) assessed vancomycin release in inhibitory doses, and (3) determined whether they would permit cell adhesion, proliferation, and mineralization in vitro. We molded 250 vancomycin-containing (VC) and 125 vancomycin-free (VUC) composites using PLLA, beta-TCP, and chloroform. One hundred twenty-five VC composites were further dip-coated with PLLA (CVC) to delay antibiotic release. Composites were characterized according to their pore structure, size, volume, density, and surface area. Vancomycin release and bioactivity were determined. Adhesion, proliferation, and mineralization were assessed for two and three replicates on Days 3 and 7 with mesenchymal stem (MSC) and Saos type 2 cells. Pore size, volume, apparent density, and surface area of the CVC were 3.5 +/- A 1.9 mu m, 0.005 +/- A 0.002 cm(3)/g, 1.18 g/cm(3) and 3.68 m(2)/g, respectively. CVC released 1.71 +/- A 0.13 mg (63.1%) and 2.49 +/- A 0.64 mg (91.9%) of its vancomycin on Day 1 and Week 6, respectively. MSC and Saos type 2 cells attached and proliferated on composites on Days 3 and 7. Vancomycin-containing PLLA/beta-TCP composites release antibiotics in inhibitory doses after dip coating and appeared biocompatible based on adhesion, proliferation, and mineralization. Vancomycin-containing PLLA/beta-TCP composites may be useful for controlling MRSA but will require in vivo confirmation.Wo

Mesenchymal Stem Cells and Nano-Bioceramics for Bone Regeneration

Orthopedic disorders and trauma usually result in bone loss. Bone grafts are widely used to replace this tissue. Bone grafts excluding autografts unfortunately have disadvantages like evoking immune response, contamination and rejection. Autografts are of limited sources and optimum biomaterials that can replace bone have been searched for several decades. Bioceramics, which have the similar inorganic structure of natural bone, are widely used to regenerate bone or coat metallic implants. As people continuously look for a higher life quality, there are developments in technology almost everyday to meet their expectations. Nanotechnology is one of such technologies and it attracts everyone's attention in biomaterial science. Nano scale biomaterials have many advantages like larger surface area and higher biocompatibility and these properties make them more preferable than micro scale. Also, stem cells are used for bone regeneration besides nano-bioceramics due to their differentiation characteristics. This review covers current research on nano-bioceramics and mesenchymal stem cells and their role in bone regeneration

Treatment Of Implant-Related Methicillin-Resistant Staphylococcus Aureus Osteomyelitis With Vancomycin-Loaded Vk100 Silicone Cement: An Experimental Study In Rats

Introduction: The purpose of this present study is to investigate the efficacy of vancomycin-loaded VK100 silicone cement drug delivery system in the treatment of implant-related methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis in rats. Materials and Methods: Thirty-six adult (18-20 weeks old) female Sprague-Dawley rats were included in the study. All rats underwent experimental osteomyelitis surgery via injecting 100 mu L bacterial suspension of MRSA into the medullary canal. After a 2-week duration for the formation of osteomyelitis model, rats were assigned Introduction: randomly into four groups: control (C), systemic vancomycin (V), local vancomycin-loaded VK100 silicone cement (vVK100), and systemic vancomycin and local vancomycin-loaded VK100 silicone cement (V+vVK100). The following treatment protocols were administered to each group for 4 weeks. For group C, 0.9% saline solution equivalent to the volume of vancomycin dose (approximately 1 ml/kg) was administered intraperitoneally twice daily (12-h intervals). For group V, 15 mg/kg of vancomycin was administered intraperitoneally twice daily (12-h intervals). For group vVK100, vVK100 polymer was included so that the intramedullary canal of the rats are affected. For group V+vVK100, vVK100 polymer was included so that the intramedullary canal of the rats are affected and 15 mg/kg of vancomycin was administered intraperitoneally twice daily (12-h intervals). After 4 weeks of treatment, clinical, radiologic, microbiologic, and histopathologic evaluations were performed for all groups. Results: Results of this study revealed that all scores of the evaluation criteria for the treatment groups (groups V, vVK100, and V+vVK100) decreased due to the treatment protocols when compared to group C. These results show the effectiveness of all treatment protocols for the implant-related chronic MRSA osteomyelitis. However, there were no statistical difference between these three protocols. Conclusions: vVK100 polymer, as a local antibiotic delivery system, seems to be an effective method for the treatment of implant-related chronic MRSA osteomyelitis.WoSScopu

Vancomycin containing PLLA/β-TCP controls experimental osteomyelitis in vivo

BACKGROUND: Implant-related osteomyelitis (IRO) is recently controlled with local antibiotic delivery systems to overcome conventional therapy disadvantages. In vivo evaluation of such systems is however too little. QUESTIONS/PURPOSES: We asked whether vancomycin (V)-containing poly-l-lactic acid/β-tricalcium phosphate (PLLA/β-TCP) composites control experimental IRO and promote bone healing in vivo. METHODS: Fifty-six rats were distributed to five groups in this longitudinal controlled study. Experimental IRO was established at tibiae by injecting methicillin-resistant Staphylococcus aureus (MRSA) suspensions with titanium particles in 32 rats. Vancomycin-free PLLA/β-TCP composites were implanted into the normal and infected tibiae, whereas V-PLLA/β-TCP composites and coated (C)-V-PLLA/β-TCP composites were implanted into IRO sites. Sham-operated tibiae established the control group. Radiological and histological scores were quantified with microbiological findings on weeks 1 and 6. RESULTS: IRO is resolved in the CV- and the V-PLLA/β-TCP groups but not in the PLLA/β-TCP group. MRSA was not isolated in the CV- and the V-PLLA/β-TCP groups at all times whereas the bacteria were present in the PLLA/β-TCP group. Radiological signs secondary to infection are improved from 10.9 ± 0.9 to 3.0 ± 0.3 in the V-PLLA/β-TCP group but remained constant in the PLLA/β-TCP group. Histology scores are improved from 24.7 ± 6.5 to 17.6 ± 4.8 and from 27.6 ± 7.9 to 32.4 ± 8.9 in the CV-PLLA/β-TCP and the V-PLLA/β-TCP groups, respectively. New bone was formed in all the PLLA/β-TCP group at weeks 1 and 6. CONCLUSIONS: CV- and V-PLLA/β-TCP composites controlled experimental IRO and promoted bone healing. CLINICAL RELEVANCE: CV- and V-PLLA/β-TCP composites have the potential of controlling experimental IRO and promoting bone healing