Background: Surgeons use various irrigation solutions to minimize the risk of prosthetic joint infection after total joint arthroplasty. The toxicity of these solutions is an important consideration in their use. This study investigates the effect of irrigation solutions Bacitracin, Clorpactin (sodium oxychlorosene), and Irrisept (chlorhexidine) on osteoblast cytotoxicity and proliferation. Methods: Four replicates of 6 conditions at 3 time points (1, 2, and 4 min) were tested: control (normal saline), Bacitracin (33 IU/ml), Clorpactin (0.05%, 0.1%, 0.2%), and Irrisept (0.05% chlorhexidine gluconate). Human osteoblasts were cultured at 37 C and 5% CO 2 until confluent monolayers were obtained. The treatment solution was applied, and cells were washed 3x with warm phosphate-buffered saline and then supplemented with a fresh medium. Phase-contrast images were taken before and after treatment. The cytotoxicity and proliferation of the treated cells was measured for all conditions on day 3 and day 5 after treatment using the alamarBlue assay. Results: All test conditions showed morphological changes to cells after treatment; controls did not. Cells demonstrated curling and detachment. This effect was the worst and permanent with Irrisept, whereas other treatments showed a return to normal morphology after 1 week. All treatments showed increased %alamarBlue reduction after 5 days except Irrisept, which showed decreased reduction. There was no statistically significant time or dose dependence with Clorpactin treatment. Conclusions: Clorpactin and Bacitracin are damaging to human osteoblast cells in vitro as compared with normal saline. This damage is at least partially reversible as shown by morphology and cell viability assay. Irrisept caused more damage than either Clorpactin or Bacitracin, and the damage was not reversible.
Designing hydrogels for controlled drug delivery remains a big challenge. We developed a calcium polyphosphate hydrogel (CPP) as matrix for delivery of vancomycin (VCM) and erythromycin (EM) by unique ionic binding and physical wrapping. In this continuing study, we investigated if gel discs prepared by mechanical compaction (at 3000 psi pressure, C-discs) is superior to that of discs prepared by regular manual compaction (M-discs) for the release of VCM and EM (10 wt.%). Data demonstrated a significant reduction of burst release of VCM and EM in C-discs (1.8% and 5%, respectively) as compared to that from M-discs within 72 hr (55% and 60%, respectively, p < 0.05). In addition, C-discs significantly extended the VCM release (1500 hr) and EM (800 hr) as compared to M-discs (160 and 96 hr, respectively, p < 0.05). The VCM released from C-discs retained its bactericidal activity much longer (1500 hr) than that from M-discs (700 hr, p < 0.05). Raman Spectroscopy indicated an ionic bond of both VCM and EM with fully hydrated polyphosphate chains of CPP hydrogel matrix for both M-discs and C-discs. Micro CT showed that C-discs had much denser microstructures and less number/depth of microcracks as a result of high pressure. We propose that CPP hydrogel represents an excellent tool for the controllable and sustained delivery of VCM and EM. Extensive experiments are currently underway to evaluate the potential impacts of the modification of compaction techniques, other antibiotics, gel concentrations on the drug release, degradation behavior and infection control both in vitro and in vivo.antibiotic delivery, bone graft substitute, calcium polyphosphate, hydrogel Highlights• Calcium polyphosphate hydrogel (CPP) represents a better ceramic matrix for delivery of vancomycin (VCM) and erythromycin (EM) by unique ionic binding and physical wrapping• Mechanical compaction method significantly extends the VCM (1500 hr) and EM (800 hr) release as compared to manual compaction method (160 and 96 hr, respectively)• VCM released from mechanically compacted discs (1500 hr) show longer bactericidal activity than that from manually compacted discs (700 hr)• Mechanical compaction significantly increased the gel density and reduced the number and depth of microcracks as a result of applied pressure
A self-setting, injectable polymeric dicalcium phosphate dehydrate bone graft substitute that is mechanically strong and has excellent cohesion was developed.We assessed the performance of erythromycin-loaded polymeric dicalcium phosphate dehydrate cement. Its properties include drug release, growth inhibition against Staphylococcus aureus and biocompatibility with osteoblastic MC3T3 cells.The impact of erythromycin loading on cement injectability, setting time, and mechanical strength were also evaluated. A sustained, low burst release of erythromycin was observed. Eluents collected from erythromycin-loaded cement showed a considerable zone of inhibition for up to 28 days. Direct contact of erythromycin-loaded cement discs with agar plate showed a similarly sizable zone of inhibition for up to 22 days. Degraded ceramic residues had strong zones of inhibition as well. While the erythromycin-loaded cement was injectable, a notable delay of the setting time was observed (49.2 ± 6.8 min) as compared with control (drug-free cement, 12.2 ± 2.6 min). A slight increase in compressive strength (60.83 ± 6.28 MPa) was observed in erythromycin-loaded cement as compared with control (59.41 ± 6.48 MPa). Erythromycin-loaded cement was biocompatible although reduced cell growth was observed in the presence of the cement eluent.We propose that the bactericidal efficacy of erythromycin-loaded cement was caused by the combined effects of erythromycin released and exposed on the contact surface of degrading ceramics. Our data may elucidate the future application of polymeric dicalcium phosphate dehydrate bone graft substitute for the treatment of orthopedic infections and opportunities to use other antibiotics and applications considering its comparable handling and mechanical strength to poly (methyl methacrylate) cements.
<b><i>Introduction:</i></b> Multiple irrigation solutions are used in orthopedic surgeries although there are limited studies on their lasting effects on human tissues. The purpose of this work was to investigate the cytotoxic effects of the irrigation solutions Bacitracin, Clorpactin (sodium oxychlorosene), Irrisept (0.05% chlorhexidine gluconate), and Bactisure (ethanol 1%, acetic acid 0.6%, sodium acetate 0.2%, benzalkonium chloride 0.013%, and water) on 3D cultures of human fibroblasts. <b><i>Methods:</i></b> Two independent experiments with 6 replicates were performed for the following conditions: Control (saline), bacitracin, Clorpactin, Irrisept, and Bactisure. Human fibroblast cell sheets were exposed to these solutions (1 or 2 min), followed by three washes with warm saline. Cell sheets were then cultured for additional 5- and 7-day posttreatment. Cell viability was measured using the alamarBlue (AB) assay. The more cytotoxic the irrigant, the lower the AB reduction. <b><i>Results:</i></b> For 1-min exposure time, significant differences in AB reduction were noted in Clorpactin, Irrisept, and Bactisure groups compared to control at both 5 days (Clorpactin <i>p</i> = 0.0003, Irrisept <i>p</i> = 7.31 × 10<sup>−15</sup>, Bactisure <i>p</i> = 6.86 × 10<sup>−14</sup>) and 7 days posttreatment (all groups <i>p</i> < 0.0001). The results were similar in the 2-min exposure groups. Bacitracin-treated fibroblasts displayed no significant difference at all measurement times compared to control. <b><i>Discussion:</i></b> Impacts of irrigation solution exposure on cell viability were varied. Irrisept and Bactisure showed the highest cell toxicity even after a brief exposure (1 min), while bacitracin and Clorpactin exposure showed smaller impacts on cell viability as compared to saline controls. This in vitro study provided insight into the effects of the irrigants on human cells and provides the groundwork essential to move to in vivo studies. Our findings raised the concern that some irrigation solutions may have negative impacts on wound healing and healthy cellular response.
Background: Direct attachment of tendons to metallic implants is important in orthopedics. Tissue integration depends on scaffold microstructure and composition. This study evaluated the effect of pore size of titanium on the viability and function of fibroblasts and tenocytes in a dynamic bioreactor.Methods: Standardized Ti porous cylinders with 3 pore sizes (400, 700, and 1000 mm) were seeded with fibroblasts or tenocytes (4500 cells/mL) in silicon tubes. Cells were analyzed via alamarBlue (AB) assay in addition to scanning electron microscopy at day 7 (fibroblasts) or day 8 (tenocytes) and day 15. AB functions as a cell health indicator where functional living cells reduce the resazurin dye (blue) in the solution to resorufin (pink), and cell viability can be quantified via spectroscopy. Results: At day 7, fibroblasts cultured on all sizes reduced AB, with significant differences noted between 400 vs 1000 mm (P ¼ .013) and 700 vs 1000 mm (P ¼ .001). At day 15, fibroblasts reduced AB on all sizes with a significant difference noted between 700 vs 1000 mm (P ¼ .004). Fibroblasts on all 3 pore sizes increased AB reduction from day 7 to day 15. Tenocytes reduced AB with significant differences between the 400 vs 700 mm (P ¼ .049) and the 400 vs 1000 mm pore sizes at day 8. In contrast, tenocyte reduction of AB decreased from day 8 to day 15. Scanning electron microscopy performed on fibroblast cylinders showed fibroblasts reached the surface of the cylinders, confirming interconnectivity. Conclusions: While both fibroblasts and tenocytes penetrated the pores, fibroblasts preferred larger size, whereas tenocytes favored smaller size. Results are encouraging since soft-tissue attachment to a metallic scaffold is difficult but clinically desirable. Future studies could be performed in an in vivo animal model.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.